Dinuclear Alkynyl Gold(I) Complexes Containing Bridging N

Article pubs.acs.org/Organometallics

Dinuclear Alkynyl Gold(I) Complexes Containing Bridging N‑Heterocyclic Dicarbene Ligands: New Synthetic Routes and Luminescence Juan Gil-Rubio,*,† Verónica Cámara,† Delia Bautista,‡ and José Vicente*,† †

Grupo de Química Organometálica, Departamento de Química Inorgánica, Facultad de Química, Universidad de Murcia, E-30071 Murcia, Spain ‡ SAI, Universidad de Murcia, E-30071 Murcia, Spain S Supporting Information *

ABSTRACT: A series of dinuclear alkynyl gold(I) complexes of the type [(AuCCR′)2{μ-(Im-R)2(CH2)n}] (R′ = tBu, SiMe3, Ph, C6H4X-4 (X = OMe, CF3, or NO2), 3-pyridyl (Pyl), 2,2′-bipyridin-5-yl (Bpyl); Im-R = N-methylimidazol-N-yl-2ylidene (Im-Me), N-butylimidazol-N-yl-2-ylidene (Im-Bu), Nbenzylimidazol-N-yl-2-ylidene (Im-Bz); n = 1, 3, 5) have been synthesized by (1) deprotonation of arylacetylenes with K2CO3 in the presence of [(AuCl)2{μ-(Im-R)2(CH2)n}], (2) the “acac method”, i.e., the reaction of [(AuCl)2{μ-(ImR)2(CH2)n}] with Tl(acac) and, subsequently, with HCCR′, and (3) the reaction of [Au(CCR′)]n with [(AgBr)2{μ-(ImR)2(CH2)n}]. In addition, mononuclear complexes [(AuCCR′)(Im-R2)], where Im-R2= N,N′-dimethylimidazol-2-ylidene and R′ = SiMe3 or Im-R2 = N,N′-dibenzylimidazol-2-ylidene and R′ = tBu, have been prepared by method 2 or 3, respectively. A dinuclear complex containing two AuCl units connected by an acyclic dicarbene ligand results from the attack of N,N′diethylpropylenediamine to the isocyanide ligand of [AuCl(CNtBu)]. The photophysical properties of the new gold(I) chloro and alkynyl bis(carbene) complexes have been studied. Most of the dinuclear alkynyl complexes prepared are emissive at room temperature in the solid state or in solution. Complexes derived from aryl- or heteroarylalkynes give structured emissions that have been assigned to gold-perturbed intraligand 3[π→π*](CCAr) excited states.

■

INTRODUCTION Alkynyl gold(I) complexes have been extensively studied because they combine singular structural and photophysical features.1 Their most remarkable structural features are related to their rod-like geometry and their marked tendency to form aggregates by intra- or intermolecular aurophilic interactions,2 which make them interesting building blocks for the synthesis of organometallic rod-shaped oligomers and polymers,3−6 liquid crystals,7,8 macrocycles,4,9,10 catenanes,4 helicates,11 and dendrimers.12 Their photophysical behavior is characterized by a strong spin−orbit coupling, leading to emissive triplet states, the energy and luminescence efficiency of which can be deeply affected by the aurophilic interactions.13 These properties have been exploited to prepare ion probes,14,15 molecular switches,16 and electroluminescent devices.17,18 In contrast with the extensively studied alkynyl gold(I) complexes with auxiliary phosphine ligands,1 alkynyl(carbene) gold(I) derivatives have received only little attention.3,19−30 The first such compounds were obtained by reacting alkynyl isocyanide complexes with amines (Scheme 1), which afforded acyclic diaminocarbene complexes.22 This method was successfully applied to di- and trialkynyl derivatives.3,19,20,22 Gold(I) alkynyls containing N-heterocyclic carbene (NHC) ligands have been obtained (Scheme 1) (a) by reacting a © 2012 American Chemical Society

Scheme 1

NHC(chloro) gold(I) complex with a terminal alkyne in the presence of base,23,25,28,29 (b) by transmetalation using MgCl(CCH)24 or [Ag(CCPh)]n,23 (c) by reacting a Received: May 18, 2012 Published: August 1, 2012 5414

dx.doi.org/10.1021/om300431r | Organometallics 2012, 31, 5414−5426

Organometallics

Article

bond cleavage. Unfortunately, no good-quality single crystals of the new silver complexes were obtained; in addition, as they are soluble only in d6-DMSO, no low-temperature NMR studies could be conducted. Complexes LnRAg2Br2 are effective carbene-transfer agents,35 reacting with [AuCl(SMe2)] at room temperature to give good yields of complexes LnRAu2Cl2 (Scheme 2). The NMR spectra of the gold(I) complexes obtained agree with their symmetrical structures, and the C−Au carbon nucleus is more shielded than in LnRAg2Br2, giving a narrow singlet in the range 169.7−172.7 ppm. Dinuclear alkynyl gold(I) complexes LnR(AuCCR′)2 were prepared using three different methods (Scheme 3):

hydroxo(carbene) gold(I) complex with a terminal alkyne or with a 1-trimethylsilylalkyne,26,27 or (d) by replacement of PR3 by a NHC ligand in [Au(CCR)(PR3)].18 Some of them are photoluminescent, and their emissions have been attributed to metal-perturbed alkynyl-based states.23,25,26,28 In addition, several patents have reported the application of mononuclear alkynyl(carbene) gold(I) complexes as emitters in electroluminescent devices.18 Complexes containing two or more alkynyl gold(I) units connected by a multidentate phosphine or isocyanide ligand have been studied because of their aurophilic interactions and luminescence.10,14,31−33 In recent years, bidentate NHC ligands with variable geometry, steric bulk, and donor ability have become available.34,35 Herein we report the first series of dinuclear gold(I) alkynyls containing bridging dicarbene ligands. In addition, we have developed two new synthetic routes for this type of compound: (a) the reaction of acetylacetonato(carbene) gold(I) complexes with terminal alkynes (“acac” method),36 and (b) the carbene-transfer reaction from a silver carbene complex to an acetylide gold(I) derivative. Finally, the photophysical properties of the new alkynyl complexes have been studied and compared to those of related alkynyl(phosphino) gold(I) compounds.

Scheme 3

■

RESULTS AND DISCUSSION Synthesis and Structural Characterization. Silver carbene precursors LnRAg2Br2 (Scheme 2) were obtained in Scheme 2

Method A: By reacting chloro complexes LnRAu2Cl2 with Tl(acac) (acac = acetylacetonato) and, subsequently, with HCCR′ (R′ = alkyl, aryl, or trimethylsilyl). In this application of the “acac” method,36 we could not isolate the intermediate acetylacetonato complexes owing to their low stability. It should be noted that this method allows the synthesis of gold(I) trimethylsilylethynyl carbene complexes avoiding basepromoted desilylation. Method B: The reaction of [Au(CCR)]n with silver complexes LnRAg2Br2. This new method of synthesis of carbene gold(I) acetylides makes use of two well-known facts: (i) [Au(CCR)]n polymers react with neutral or anionic ligands, such as phosphines,3,14,19,20,32,44−47 isocyanides,3,8,15,16,19,20,45−48 or Cl−,49 to give complexes of the type [Au(CCR)L] or [Au(CCR)Cl]−, respectively, and

high yield by reacting the corresponding diimidazolium bromides (LnRH2)Br2 (R = benzyl (Bz), n = 137 or 3;38 R = n Bu, n = 139 or 3;40 R = Me, n = 341 or 542) with Ag2O in acetonitrile. The synthesis and X-ray crystal structures of complexes L1BzAg2Br243 and L5MeAg2Br242 have been already reported, showing that the former is a tetranuclear species, [Ag4(μ-Br)4(μ-L1Bz)2], while the second can be described as [Ag2(μ-L5Me)2][AgBr2]2. The NMR spectra of complexes LnRAg2Br2 show the resonances expected for the symmetrical dicarbene ligands. A broad singlet in their 13C{1H} NMR spectrum (179.1−180.9 ppm, RT), corresponding to the C−Ag carbon nuclei, suggests a fast exchange process involving Ag−C 5415


Organometallics

Article

(ii) silver carbene complexes are good carbene-transfer agents.35,50 We note that, even though AgBr precipitation occurs during the reaction, the crude gold alkynyls still contained some soluble silver impurity, which was removed by stirring their solutions with excess Na2S2O3·5H2O. Method C: The reaction of a chloro complex LnRAu2Cl2 with HCCR′ in the presence of K2CO3. This method failed for the reactions of L3RAu2Cl2 (R = nBu or Me) with HCCPh, affording impure L3R(AuCCPh)2, and for the reaction of L5MeAu2Cl2 with HCCtBu, which gave a mixture where the expected alkynyl L5Me(AuCCtBu)2 was a minor component. Complexes LRAuCCR′ (Chart 1) were prepared from LMeAuCl51 and HCCSiMe3 using method A or from [Au(CCtBu)]n and LBzAgBr52 using method B. Chart 1

Figure 1. Molecular structure of L3Bu(AuCCPh)2 showing the interaction between pairs of molecules (50% thermal ellipsoids). Selected bond lengths (Å) and angles (deg): Au(1)−C(1) 2.017(4), Au(1)−C(2) 1.988(5), C(2)−C(3) 1.215(6), Au(2)−C(4) 2.021(5), Au(2)−C(5) 1.986(5), C(5)−C(6) 1.201(6), Au(3)−C(51) 2.028(5), Au(3)−C(52) 1.989(5), C(52)−C(53) 1.207(6), Au(4)−C(54) 2.017(4), Au(4)−C(55) 1.996(5), C(55)−C(56) 1.204(6), Au(1)− Au(4) 3.3898(4); C(2)−Au(1)−C(1) 174.58(18), C(5)−Au(2)− C(4) 177.78(19), C(52)−Au(3)−C(51) 178.40(19), C(55)−Au(4)− C(54) 177.43(18).

The NMR spectra of the gold alkynyl carbene complexes gave the expected signals according to the high symmetry of the molecules. The C−Au carbene carbon nuclei are deshielded by ca. 16 ppm with respect to their parent chloro complexes LnRAu2Cl2, which could be attributed to the stronger trans influence of the alkynyl ligand and the greater electronegativity of the chloro ligand. The chemical shifts of the acetylenic carbons were not significantly affected by the nature of the substituents of the carbene ligands, but depended on the alkyne substituents as previously noted.22 In the IR spectra of all complexes, the ν(CC) bands appeared in the range 2020− 2116 cm−1. The crystal structure of L3Bu(AuCCPh)2 has been determined (Figure 1). Acyclic diamino carbene (ADC) gold(I) complexes have been obtained by reacting amines with isocyanide gold(I) complexes.21,45 We have attempted the synthesis of dinuclear Au(I) alkynyls containing bridging ADC ligands by using this method. Thus, compound L3*Au2Cl2 was prepared from [AuCl(SMe2)], tert-butylisocyanide, and N,N′-diethylpropylenediamine (Scheme 4), and its X-ray crystal structure was determined (Figure 2). However, the reactions of L3*Au2Cl2 with BpylCCH by using several base/solvent combinations (NEt3/CD2Cl2, K2CO3/CD2Cl2 or CD3COCD3, KOtBu/ CD2Cl2, NaOH/THF) gave mixtures that could not be separated and characterized. The “acac” method or the reaction between [Au(CCBpyl)(CNtBu)] and MeHN(CH2)6NHMe in a 2:1 molar ratio gave also inseparable mixtures. Crystal Structures. The crystal structures of L3Bu(AuC CPh)2 and L3*Au2Cl2 were determined by single-crystal X-ray diffraction. The coordination geometry is linear in both cases (C−Au−X in the range 174.58−178.95°). The Au−Ccarbene and Au−Calkynyl bond distances (2.017−2.028 and 1.986−1.996 Å, respectively) are comparable to those found in alkynyl(NHC) gold(I) complexes,20,21,24−26,28,53 whereas the Au−Ccarbene and Au−Cl bond distances of L3*Au2Cl2 (2.003−2.015 and 2.2821−2.3012 Å) are comparable to their homologues in reported chloro(ADC) gold(I) complexes.54

Scheme 4

The structure of L3Bu(AuCCPh)2 shows aurophilic interactions between two gold atoms of adjacent molecules (Figure 1). The Au−Au distance is 3.3898(4) Å, and the two mutually interacting molecules are independent, differing mainly in the conformation of the nBu chains. The structure of L3*Au2Cl2 (Figure 2) shows three independent molecules, which present small differences in their conformation. No aurophilic contacts were observed in this case (the shortest Au−Au distance is 5.116 Å), which could be attributed to the bulk of the dicarbene ligand. Electronic Absorption Spectroscopy. Complexes LnR(AuCCR′)2 display absorption bands in the high-energy region (Tables 2 and 3 and Figure 3) with λmax values (λmax ≤ 242 nm) similar to those shown by LnRAu2Cl2 (Table 1) or LMeAuCl51 (234 and 247 nm). Hence, these bands are tentatively assigned to transitions located mainly on the gold−carbene unit. In addition, all the alkynyl complexes studied, except L3R(AuCCC6H4NO2-4)2 (R = Bz or nBu), give intense absorptions in the range 257−332 nm with energies depending mainly on the substituent of the alkynyl unit. The appearance and λmax values of the spectra are similar 5416


Organometallics

Article

≈ Me3Si < 4-X-C6H4 (X = H, MeO, CF3) ≈ Pyl < Bpyl) may be attributed to the increase in π-electron delocalization. Compounds L1Bz(AuCCPh)2 and LnBu(AuCCtBu)2 (n = 1 or 3) display weak absorptions in the 318−330 nm region, which could not be assigned. The low-energy region of the spectra of L3R(AuC CC6H4NO2-4)2 (R = Bz or nBu; Figure 7) is dominated by a strong band at 346 or 347 nm (CH2Cl2), respectively. This absorption shows a modest solvatochromism (for R = nBu, λmax is 345 or 350 nm in toluene or butyronitrile, respectively) and is tentatively assigned to a IL [π→π*] transition involving goldperturbed states located in the CCC6H4NO2 unit. The redshift of this absorption with respect to its homologues in the remaining phenylethynyl complexes is attributed to some charge-transfer character induced by the nitro group. The phosphine counterparts [Au(CCC6H4NO2-4)(PR3)] (R = Cy or Ph) give a band with similar λmax values (336 and 340 nm, respectively), which has been assigned to an intraligand charge-transfer (ILCT) transition.57 Luminescence. Complexes LnRAu2Cl2. Previous studies23,51 have reported that complexes of the type [AuCl(NHC)] (NHC = 1,3-dimethylimidazol-2-ylidene, 1,3-dimethyltriazol-2-ylidene, or 1,3-dimethylbenzimidazol-2-ylidene) give two bands in the solid state, with emission maxima in the ranges 410−435 and 580−650 nm, which were assigned to IL(NHC) and Au···Au excited states, respectively. Similarly, solid biscarbene complexes LnRAu2Cl2 give an emission with λmax in the range 423− 452 nm (Table 1 and Figure S1). These bands are broad at room temperature, but in glassy butyronitrile display shoulders indicating vibronic structure (Figure S2). In CH2Cl2 at 298 K they do not emit. Considering the structured character, the microsecond lifetimes, and the close similarity of these bands with the high-energy bands of their mononuclear counterparts,23,51 they are assigned to gold-perturbed 3IL(NHC) states. Additionally, solid L3MeAu2Cl2 shows a broad structureless band at 611 nm, which is attributable to a Au···Au emission. The presence of aurophilic interactions in this complex is not surprising considering that L3Me is the less bulky ligand of the series, being flexible enough to allow an intramolecular Au···Au contact, as observed for complex [Au2(μ-L3Me)2]2+.58 Unfortunately, we could not obtain single crystals of L3MeAu2Cl2 for an X-ray structural confirmation of this assignment. Complexes LnR(AuCCR′)2 (R′ = tBu or SiMe3). In CH2Cl2 at 298 K (Table 2), only L1R(AuCCtBu)2 (R = Bz or nBu) are emissive, giving a broad emisssion around 395 nm and a very weak emission around 520 nm (Figure S3). In glassy butyronitrile (77 K) their emissions show vibrational structure (Figure S4). The solid-state spectra (298 K) of LnR(AuC CtBu)2 (n = 1, R = Bz or nBu, and n = 3, R = nBu) show a broad emission around 450 nm. In contrast, solid L3Bz(AuCCtBu)2 (Figure 4) gives a structured emission with λ0−0 = 413 nm and vibronic progressions of 1155, 1516, and 2060 cm−1, and solid L3Bu(AuCCSiMe3)2 (Figure 4) gives a broad emission at 370 nm and a weak structured emission with λ0−0 = 423 nm with vibronic progressions of 1067, 1517, and 1996 cm−1. The lifetimes of all solid-state emissions are in the microsecond range. Considering their Stokes shifts, vibronic progressions, and lifetimes, we attribute the solid-state emissions of L3Bz(AuCCtBu)2 and L3Bu(AuCCSiMe3)2 (low-energy emission) to gold-perturbed 3[π→π*](CC) states. For the other emissions, a gold-perturbed IL(NHC) character is tentatively assigned. Although the differences between the solution and solid-state spectra of L1R(AuCCtBu)2 (R = Bz

Figure 2. Molecular structure of L3*Au2Cl2 (50% thermal ellipsoids). Selected bond lengths (Å) and angles (deg): Au(1)−C(1) 2.015(4), Au(1)−Cl(1) 2.3012(10), Au(2)−C(5) 2.004(4), Au(2)−Cl(2) 2.2834(10); C(1)−Au(1)−Cl(1) 178.85(12), C(5)−Au(2)−Cl(2) 178.95(12).

Table 1. Electronic Absorption and Luminescence Data of LnRAu2Cl2 absorptiona

luminescenceb

λabs/nm (ε/104 dm3 mol−1 cm−1)

λexc/ nm

L1BzAu2Cl2

230 (1.33), 237 (1.38), 251 (1.59)

365 273

L3BzAu2Cl2

229 (1.70, sh), 236 (1.84), 249 (1.95)

322

complex

270 L1BuAu2Cl2

230 (2.89), 236 (2.89), 250 (3.19)

315 271

L3BuAu2Cl2

234 (1.49), 248 (1.64)

330 275

L3MeAu2Cl2

235 (1.87), 247 (1.91)

320 270

L5MeAu2Cl2

228 (3.0), 233 (2.93), 248 (3.09)

322 270

medium solid n PrCN glass solid n

PrCN glass solid n PrCN glass solid n

PrCN glass solid n PrCN glass solid n PrCN glass

λem/nm [τ/ μs] 438 409 432 [0.96, 5.07] 408 423 409 441 [1.05, 7.23] 350, 420 452, 611 408 429 408

Measured in CH2Cl2 solution (2.1 × 10−5 to 2.4 × 10−5 M) at 298 K. Measured in the solid state (T = 298 K) or glassy butyronitrile solution (1 × 10−6 to 1.8 × 10−6 M; T = 77 K).

a b

to those of gold(I) alkynyls containing phosphine or isocyanide ligands, some examples being [Au(CCPh)(PCy3)] (λmax = 290 nm),55 [Au(CCPh)(PPh3)] (284 nm),56 [Au(C CBpyl)(PEt3)] (316 nm),47 [Au2(CCPh)2(μ-dppe)] (284 nm),56 or [Au(CCPh)(CNC6H3Me2-2,6)] (288, 274 nm). Therefore, taking into account previous studies,5,55 we tentatively propose these absorptions to be mostly of intraligand (IL) [π→π*](CC or CCAr) character with some participation of Au orbitals. Accordingly, the shifts to lower energies on varying the alkynyl substituent (the λmax value of the lowest-energy maximum increases in the order tBu 5417


Organometallics

Article

Table 2. Electronic Absorption and Luminescence Data of LnR(AuCCR′)2 (R′ = tBu or Me3Si) absorptiona complex

luminescenceb


λexc/ nm

L1Bz(AuCCtBu)2

240 (2.03, sh), 264 (2.62), 318 (0.24), 330 (0.22)

L3Bz(AuCCtBu)2

240 (1.97, sh), 261 (2.99)

L1Bu(AuCCtBu)2

240 (2.46, sh), 263 (4.41), 330 (0.16, sh)

L3Bu(AuCCtBu)2

240 (2.82, sh), 261 (4.88), 325 (0.05, sh)

350 350 350 350

L3Bu(AuCCSiMe3)2

242 (2.00, sh), 262 (2.95)

270 300

350 350 350 280

270 −5

medium

λem/nm [τ/μs]

solid CH2Cl2 n PrCN glass solid CH2Cl2 n PrCN glass solid CH2Cl2 n PrCN glass solid CH2Cl2 n PrCN glass solid CH2Cl2 n PrCN glass

451 [0.70, 6.80] 395, 522 (weak) 415, 485 (sh) 416, 437, 444, 455 [191.8] nonemissive nonemissive 446 [0.73, 5.34] 394, 517 (weak) 415, 430 (sh), 487 (sh) 455 [0.85, 4.88] nonemissive 360, 443 370 [0.37, 1.01], 423 (weak), 443 (sh), 452 (sh), 462 (sh) nonemissive 364, 421 (sh)

Measured in CH2Cl2 solution (ca. 2 × 10 M) at 298 K. Measured in the solid state (T = 298 K), deoxygenated CH2Cl2 solution (ca. 2 × 10−5 M; T = 298 K) or glassy butyronitrile solution (1.3 × 10−6 to 2.2 × 10−6 M; T = 77 K).

a

b

Table 3. Electronic Absorption and Luminescence Data of LnR(AuCCR′)2 (R′ = Aryl, Pyl, or Bpyl) absorptiona compound

luminescenceb


L1Bz(AuCCPh)2

238 (4.40), 265 (4.20, sh), 274 (4.30), 284 (4.30)

L3Bz(AuCCPh)2

239 (3.70), 260 (3.50, sh), 272 (4.00), 283 (4.13)

L1Bu(AuCCPh)2

236 (4.79), 274 (4.48), 284 (4.92), 320 (0.30, sh)

λexc/ nm

medium

350 350 350 300 290 350

solid CH2Cl2 solid CH2Cl2 2-Me-THF glass solid CH2Cl2 n PrCN glass solid CH2Cl2 2-Me-THF glass solid CH2Cl2 solid CH2Cl2 2-Me-THF glass solid CH2Cl2 n PrCN glass solid CH2Cl2 2-Me-THF glass solid CH2Cl2 solid CH2Cl2 solid CH2Cl2 n PrCN glass solid CH2Cl2 2-Me-THF glass

L3Bu(AuCCPh)2

238 (3.09), 259 (2.67, sh), 273 (3.59), 283 (3.92)

L5Me(AuCCPh)2

238 (3.20), 257 (2.52, sh), 272 (3.35), 283 (3.62)

L3Bu(AuCCC6H4CF34)2

238 (3.31), 260 (2.97, sh), 279 (5.27), 289 (6.10)

L3Bu(AuCCC6H4OMe4)2

238 (3.60), 263 (3.18, sh), 273 (3.83, sh), 284 (4.35), 296 (3.50, sh)

L3Bu(AuCCPyl)2

238 (3.83), 258 (3.35, sh), 276 (4.43), 282 (4.21, sh)

L3Me(AuCCBpyl)2

236 (3.31), 242 (3.33), 250 (2.87, sh), 319 (6.31), 332 (6.10)

L5Me(AuCCBpyl)2

235 (4.34), 241 (4.22), 250 (3.19, sh), 319 (7.87), 331 (7.62)

L3Bz(AuCCC6H4NO24)2

236 (4.43), 346 (4.81)

270 270 350 350 290 350 270 315 270 290 360 275 275 365 300 290 350 350 350 350 350

L3Bu(AuCCC6H4NO24)2

234 (2.95), 347 (3.05)

360 350 365

λem/nm [τ/μs] 477, 510 460, 530 464 (sh), 503 [0.56, 2.28] 421, 448 419 [202.7], 438, 449, 459 410 (sh), 430 (sh), 459, 505 [0.45, 1.87] 305, 420, 440 415 [270.8], 435, 444, 456 460 (sh), 516 [0.45, 1.69] 451, 530 (sh) 419 [211.5], 438, 448, 460 416, 496, 539 [96.2], 575 (sh) 421, 445, 457 (sh) 432, 453 (sh), 471 (sh), 491 (sh) 432, 452 429 [249.5], 451, 460, 471 435 (sh), 477, 494 427, 465 422, 439, 452, 465 438 (sh), 506 430, 454 424 [193.9], 444, 454, 467 400, 507, 549 [17.0, 61.7], 585 (sh) 376, 393, 412, 430 (sh), 502, 533 413, 505, 549, 585 (sh) 376, 394, 408 (sh), 507, 536 462, 528, 557 (sh) nonemissive 413 (weak), 501, 536 453, 524, 547 (sh) nonemissive 502 [412.4], 537

Measured in CH2Cl2 solution (1.9 × 10−5 to 2.5 × 10−5 M) at 298 K. bMeasured in the solid state (T = 298 K), deoxygenated CH2Cl2 solution (1.9 × 10−5 to 2.5 × 10−5 M; T = 298 K) or glassy 2-methyltetrahydrofuran or butyronitrile solution (1.3 × 10−6 to 2 × 10−6 M; T = 77 K). a

5418


Organometallics

Article

Figure 6. Emission spectra of L3Me(AuCCBpyl)2 (298 K).

Figure 3. Absorption spectra (CH2Cl2) of selected LnR(AuCCR′)2 complexes.

Figure 7. Absorption (continuous line), excitation (77 K, λem = 500 nm, dashed line), and emission spectra (77 K, λexc = 350 nm, dashdotted line) of L3Bu(AuCCC6H4NO2-4)2. All were measured in butyronitrile.

Figure 4. Emission spectra (298 K) of solid L3Bz(AuCCtBu)2 (continuous line) and L3Bu(AuCCSiMe3)2 (dashed line).

interactions because we could not obtain single crystals suitable for X-ray diffraction after repeated attempts. Complexes LnR(AuCCR′)2 (R′ = Aryl, Pyridyl, or Bipyridyl). Complexes LnR(AuCCPh)2 (n = 1 or 3, R = nBu or Bz; n = 5, R = Me), L3Bu(AuCCC6H4X-4)2 (X = CF3 or OMe), and L3Bu(AuCCPyl)2 are emissive at 298 K in CH2Cl2 solution and in the solid state (Table 3 and Figures S5−S8). The emission maxima are in the range 420−539 nm, and the vibrational structure is poorly resolved. However, in glassy solutions of butyronitrile or 2-methyltetrahydrofuran at 77 K, they give a sharp structured emission (Figure 5) with λ0−0 in the range 415−427 nm and vibronic spacings of ca. 1100, 1550, and 2100 cm−1. Under these conditions, the excitation spectra (Figure 5) match the lower-energy absorptions (Figure 3), and lifetimes in the microsecond range could be determined. The large Stokes shifts, vibronic progressions, and lifetimes suggest a gold-perturbed intraligand 3[π→π*](CC or CCAr) character for the emitting states.5,23,28 Similar emission wavelengths and vibronic spacings have been reported for their phosphine or isocyanide counterparts, examples being [Au(CCPh)(PCy3)] (λ0−0 = 419 nm),55 [Au(CCPh)(PPh3)] (419 nm),56 [Au2(CCPh)2(μ-dppe)] (420 nm),56 or [Au(CCPh)(CNC6H3Me2-2,6)] (419 nm).33 The bipyridylethynyl compounds LnMe(AuCCBpyl)2 (n = 3 or 5) gave

Figure 5. Excitation (dashed line) and emission (continuous line) spectra of L3Bu(AuCCR′)2 [R′ = Ph (gray) or 3-pyridyl (black)] measured in glassy 2-methyltetrahydrofuran at 77 K.

or nBu) suggest the influence of intra- or intermolecular interactions, we have no structural evidence for these 5419


Organometallics

Article

nitrogen. Infrared spectra were recorded in the range 4000−200 cm−1 on a Perkin-Elmer 16F PC FT-IR spectrometer using KBr pellets. C, H, N, and S analyses were carried out with Carlo Erba 1108 and LECO CHS-932 microanalyzers. NMR spectra were measured on Bruker Avance 200, 300, and 400 instruments. 1H chemical shifts were referenced to residual CHCl3 (7.26 ppm) or d5-DMSO (2.50 ppm). 13 C{1H} and 19F NMR spectra were referenced to CDCl3 (77.1 ppm) and to external CFCl3, respectively. Abbreviations used: br (broad), sh (shoulder), q (quartet), quint (quintet), sext (sextet), Im (imidazole). Assignments of 1H and 13C{1H} NMR spectra are based on COSY, HMQC, and HMBC experiments. In the experimental data, the imidazole rings are numbered as shown in Scheme 2. Melting points were determined on a Reichert apparatus in the open air. UV−visible absorption spectra were recorded on a Perkin-Elmer Lambda 750S spectrometer in 1 cm path length quartz cuvettes. Steady-state excitation and emission spectra were measured on a Jobin Yvon Fluorolog 3-22 spectrofluorimeter with a 450 W xenon lamp, doublegrating monochromators, and a Hamamatsu R-928P photomultiplier. The solutions for luminescence measurements were deoxygenated by bubbling N2 and placed inside 1 cm path length quartz fluorescence cuvettes (298 K) under a N2 atmosphere. Low-temperature (77 K) emission measurements were carried out in quartz tubes using an optical Dewar sample holder filled with liquid N2. The solid samples were placed between quartz coverslips. Phosphorescence lifetimes were measured using an incorporated Jobin Yvon FL-1040 phosphorimeter or by time-correlated single-photon counting on a FluoroHub of IBH with pulsed diodes (NanoLed) as excitation sources (λexc = 334 or 372 nm). Synthesis of the Diimidazolium Salts. Diimidazolium salts (LnRH2)Br2 (R = Bz, n = 137 or 3;38 R = nBu, n = 139 or 3;40 R = Me, n = 341 or 542) were prepared using a modified literature method.63 A THF solution of 1-(benzyl, n-butyl, or methyl)-1H-imidazole and the corresponding Br(CH2)nBr (2:1 molar ratio) was stirred at 100 °C overnight in a Carius tube. The precipitated salts were filtered, washed with Et2O, and dried under vacuum. The yields were nearly quantitative, and their NMR data agree with those previously reported. Synthesis of Silver(I) Biscarbene Complexes. All complexes have been prepared by reaction of the bisimidazolium salt with an equimolar amount of Ag2O in acetonitrile. The resulting suspension was stirred overnight at room temperature in the dark. The light gray solids were isolated by filtration, washed with Et2O (3 × 5 mL), and dried under vacuum. The obtained compounds are soluble only in highly polar solvents such as DMSO, and their NMR spectra show only the expected signals for the carbene ligand. They were used for the synthesis of the gold complexes without further purification. L1BzAg2Br2. This was prepared from (L1BzH2)Br2 (521 mg, 1.06 mmol) and Ag2O (246 mg, 1.06 mmol). Yield: 724 mg, 1.03 mmol, 97%. The 1H and 13C{1H} NMR of the compound spectra agree with those reported.43 L3BzAg2Br2. This was prepared from (L3BzH2)Br2 (230 mg, 0.44 mmol) and Ag2O (103 mg, 0.44 mmol). Yield: 287 mg, 0.39 mmol, 89%. Anal. Calcd for C23H24N4Ag2Br2: C, 37.74; H, 3.30; N, 7.65. Found: C, 37.74; H, 3.41; N, 7.64. 1H NMR (400.9 MHz, d6-DMSO): δ 7.58 (s, 4H, CH, Im), 7.33−7.24 (m, 10H, Ph), 5.25 (s, 4H, PhCH2), 4.04 (t, 4H, CH2CH2N, 3JHH = 6.1 Hz), 2.39 (quint, 2H, CH2CH2N, 3JHH = 6.1 Hz). 13C{1H} NMR (100.8 MHz, d6-DMSO): δ 179.8 (C2, Im), 137.0 (C1, Ph), 128.7, (Ph), 128.0 (C4, Ph), 127.6 (Ph), 123.0 (CH, Im), 121.4 (CH, Im), 54.2 (PhCH2), 47.6 (CH2CH2N), 30.5 (CH2CH2N). L1BuAg2Br2. This was prepared from (L1BuH2)Br2 (131 mg, 0.31 mmol) and Ag2O (72 mg, 0.31 mmol). Yield: 165 mg, 0.26 mmol, 84%. Anal. Calcd for C15H24N4Ag2Br2: C, 28.33; H, 3.80; N, 8.81. Found: C, 26.45; H, 3.59; N, 8.10. The element ratios agree with those of the ligand, and the NMR spectra show only the expected signals for the ligand; therefore the low percentages are attributed to inorganic silver impurities, which do not affect its use as carbene-transfer reagent. 1 H NMR (400.9 MHz, d6-DMSO): δ 7.83 (d, 2H, CH, Im, 3JHH = 1.5 Hz), 7.61 (d, 2H, CH, Im, 3JHH = 1.4 Hz), 6.67 (s, 2H, NCH2N), 4.12 (t, 4H, H1, nBu, 3JHH = 7.2 Hz), 1.73 (quint, 4H, H2, nBu, 3JHH = 7.2 Hz), 1.22 (sext, 4H, H3, nBu, 3JHH = 7.2 Hz), 0.83 (t, 6H, Me, 3JHH =

dual emissions at 298 K in CH2Cl2 solution and in the solid state (Figure 6), with maxima in the ranges 376−412 and 505− 585 nm. Since these emissions closely resemble those of their diphosphine counterparts,47,59 they were similarly attributed to intraligand [π→π*](AuCCBpyl) fluorescence (high-energy emission) and phosphorescence (low-energy emission). The emission maximum of L3Bu(AuCCPh)2 in the solid state (λmax = 516 nm) is shifted to lower energies with respect to the solution spectrum (λmax = 451 nm). As this compound shows intermolecular short Au···Au contacts in its crystal structure (Figure 1), this red-shift is attributed to a perturbation of the emitting state originated by the aurophilic interaction. Similar red-shifts (Δλmax = 55−76 nm) were observed for L3Bz(AuCCPh)2, L3Bu(AuCCPyl)2, and L5Me(AuC CPh)2. Finally, the 4-nitrophenylethynyl compounds L3R(AuC CC6H4NO2-4)2 (R = nBu or Bz) are not emissive in CH2Cl2 solution at 298 K, and they are weakly emissive in the solid state. However, in butyronitrile glass, they give an emission with two maxima, at 500 and 535 nm, the spacing between them corresponding to a vibronic progression of ca. 1300 cm−1 (Figure 7). These emissions resemble that of solid [Au(C CC6H4NO2)(PCy3)],57 but differ from that of their phenylethynyl counterparts, suggesting that the emissive states of the 4-nitro-substituted complexes are different from those of the other phenylethynyl complexes studied. As the excitation maxima of the emissions of L3R(AuCCC6H4NO2-4)2 (350 or 360 nm for R = nBu or Bz, respectively) agree with their absorption maxima (Figure 7), in accord with previous studies,57 we propose that they originate from gold-perturbed IL 3[π→π*](CCAr) states with some charge-transfer character.

■

SUMMARY New gold(I) alkynyls containing NHC ligands have been prepared by the following methods: (a) the reaction of in situ generated gold(I) acetylacetonato carbene complexes with terminal alkynes; (b) the reaction of silver(I) NHC complexes with gold(I) acetylides; (c) the reaction of dinuclear gold(I) chloro carbenes with terminal alkynes in the presence of a base. Methods (a) and (b) have been used for the first time in the synthesis of NHC gold complexes. The first dinuclear alkynyl gold(I) complexes containing bridging dicarbene ligands have been prepared, and their photophysical properties have been studied. The lower-energy bands of their absorption spectra have been assigned to gold-perturbed intraligand [π→π*](C C or CCAr) transitions. The new dinuclear chloro complexes are luminescent at room temperature in the solid state, and their emissions are similar to those of their mononuclear counterparts. Most of the dinuclear alkynyl complexes are luminescent at room temperature, in particular those derived from aryl- or heteroarylalkynes, the emissive behavior of which resembles that of their phosphine analogues. Thus, they show structured emissions with lifetimes in the microsecond range, which have been assigned to goldperturbed intraligand 3[π→π*](CCAr) excited states.

■

EXPERIMENTAL SECTION

General Considerations. LBzAgBr,52 LMeAuCl,51 [Au(CCR)]n (R = Ph or tBu),60 and the alkynes HCCR (R = 4-C6H4NO261 and Bpyl62) were prepared using reported methods. HPLC-grade solvents were used as received unless otherwise stated. When necessary, CH2Cl2 was previously distilled over calcium hydride and stored under 5420


Organometallics

Article

7.2 Hz). 13C{1H} NMR (75.5 MHz, d6-DMSO): δ 180.9 (C2, Im), 122.7 (C4, Im), 121.7 (C5, Im), 63.3 (NCH2N), 51.2 (C1, nBu), 33.0 (C2, nBu), 19.2 (C3, nBu), 13.5 (Me). L3BuAg2Br2. This was prepared from (L3BuH2)Br2 (680 mg, 1.51 mmol) and Ag2O (350 mg, 1.51 mmol). Yield: 837 mg, 1.26 mmol, 83%. Anal. Calcd for C17H28N4Ag2Br2: C, 30.75; H, 4.25; N, 8.44. Found: C, 28.86; H, 3.96; N, 7.77. The element ratios agree with those of the ligand, and the NMR spectra show only the expected signals for the ligand; therefore the low percentages are attributed to inorganic silver impurities, which do not affect its use as carbene-transfer reagent. 1 H NMR (400.9 MHz, d6-DMSO): δ 7.58 (d, 2H, CH, Im, 3JHH = 1.6 Hz), 7.57 (d, 2H, CH, Im, 3JHH = 1.6 Hz), 4.02 (t, 4H, CH2CH2N, 3 JHH = 5.6 Hz), 3.95 (t, 4H, H1, nBu, 3JHH = 7.3 Hz), 2.44 (quint, 2H, CH2CH2N, 3JHH = 5.6 Hz), 1.70 (quint, 4H, H2, nBu, 3JHH = 7.2 Hz), 1.22 (sext, 4H, H3, nBu, 3JHH = 7.2 Hz), 0.85 (t, 6H, Me, 3JHH = 7.2 Hz). 13C{1H} NMR (100.8 MHz, d6-DMSO): δ 179.3 (C2, Im), 122.6 (CH, Im), 121.0 (CH, Im), 50.6 (C1, nBu), 47.1 (CH2CH2N), 32.9 (C2, nBu), 30.2 (CH2CH2N), 19.2 (C3, nBu), 13.4 (Me). L3MeAg2Br2. This was prepared from (L3MeH2)Br2 (554 mg, 1.51 mmol) and Ag2O (351 mg, 1.51 mmol). Yield: 800 mg, 1.38 mmol, 91%. Anal. Calcd for C11H16N4Ag2Br2·(CH3CN)0.4: C, 23.77; H, 2.91; N, 10.34. Found: C, 23.95; H, 2.87; N, 10.63. The amount of acetonitrile was estimated from the elemental analyses and corroborated by integration of the 1H NMR spectrum. 1H NMR (400.9 MHz, d6-DMSO): δ 7.60 (d, 2H, CH, Im, 3JHH = 1.6 Hz), 7.52 (d, 2H, CH, Im, 3JHH = 1.6 Hz), 3.95 (t, 4H, CH2CH2N, 3JHH = 5.8 Hz), 3.64 (s, 6H, Me), 2.45 (quint, 2H, CH2CH2N, 3JHH = 5.8 Hz), 2.04 (s, 1.2H, MeCN). 13C{1H} NMR (75.5 MHz, d6-DMSO): δ 180.0 (C2, Im), 124.0 (C4, Im), 120.8 (C5, Im), 46.6 (CH2CH2N), 37.9 (Me), 29.5 (CH2CH2N), 1.2 (MeCN); the MeCN signal was not detected. L5MeAg2Br2. This was prepared from (L5MeH2)Br2 (706 mg, 1.79 mmol) and Ag2O (415 mg, 1.79 mmol). Yield: 883.5 mg, 1.45 mmol, 81%. The 1H and 13C{1H} NMR spectra of the compound agree with those reported.42 L1BzAu2Cl2. [AuCl(SMe2)] (142 mg, 0.48 mmol) was added to a suspension of L1BzAg2Br2 (170 mg, 0.24 mmol) in CH2Cl2 (10 mL). The mixture was stirred for 15 h at room temperature in the dark and filtered through Celite. The filtrate was concentrated under vacuum to ca. 1 mL. Addition of Et2O (30 mL) gave a white precipitate, which was filtered, washed with Et2O (3 × 5 mL), and dried under vacuum. Yield: 159 mg, 0.20 mmol, 84%. Mp: 182 °C dec. Anal. Calcd for C21H20N4Au2Cl2: C, 31.80; H, 2.54; N, 7.06. Found: C, 31.43; H, 2.24; N, 6.95. 1H NMR (400.9 MHz, CDCl3): δ 7.85 (d, 2H, CH, Im, 3JHH = 2.0 Hz), 7.40−7.37 (m, 6H, Ph), 7.33−7.31 (m, 4H, Ph), 6.94 (d, 2H, CH, Im, 3JHH = 2.0 Hz), 6.46 (s, 2H, NCH2N), 5.36 (s, 4H, CH2Ph). 13C{1H} NMR (100.8 MHz, CDCl3): δ 172.1 (C2, Im), 133.9 (C1, Ph), 129.3 (Ph), 129.2 (C4, Ph), 128.2 (Ph), 121.8 (CH, Im), 121.6 (CH, Im), 63.1 (NCH2N), 55.7 (PhCH2). L3BzAu2Cl2. This was prepared in the same way as L1BzAu2Cl2 starting from L3BzAg2Br2 (137 mg, 0.19 mmol) and [AuCl(SMe2)] (110 mg, 0.37 mmol). Yield: 129 mg, 0.16 mmol, 83%. Mp: 196 °C. Anal. Calcd for C23H24N4Au2Cl2·(H2O)0.13: C, 33.54; H, 2.97, N, 6.80. Found: C, 33.13; H, 2.74; N, 6.90. The amount of water was estimated from the elemental analyses and corroborated by integration of the 1H NMR spectrum. 1H NMR (400.9 MHz, CDCl3): δ 7.35 (br s, Ph, 10H), 7.05 (d, 2H, H5, Im, 3JHH = 1.9 Hz), 6.91 (d, 2H, H4, Im, 3JHH = 1.9 Hz), 5.36 (s, 4H, CH2Ph), 4.25 (t, 4H, CH2CH2N, 3JHH = 6.6 Hz), 2.50 (quint, 2H, CH2CH2N, 3JHH = 6.6 Hz), 1.57 (s, 0.26H, H2O). 13C{1H} NMR (100.1 MHz, CDCl3): δ 171.4 (C2, Im), 134.9 (C1, Ph), 129.1 (Ph), 128.7 (C4, Ph), 128.3 (Ph), 121.7 (C4, Im), 119.9 (C5, Im), 55.3 (PhCH2), 47.3 (CH2CH2N), 30.4 (CH2CH2N). L1BuAu2Cl2. This was prepared in the same way as L1BzAu2Cl2 starting from L1BuAg2Br2 (178 mg, 0.28 mmol) and [AuCl(SMe2)] (173 mg, 0.59 mmol). Yield: 165 mg, 0.23 mmol, 81%. Mp: 161 °C dec. Anal. Calcd for C15H24N4Au2Cl2: C, 24.84; H, 3.34; N, 7.73. Found: C, 24.44; H, 3.15; N, 7.50. 1H NMR (300.1 MHz, CDCl3): δ 7.85 (d, 2H, H5, Im, 3JHH = 1.8 Hz), 7.00 (d, 2H, H4, Im, 3JHH = 1.8 Hz), 6.42 (s, 2H, NCH2N), 4.18 (t, 4H, H1, nBu, 3JHH = 7.2 Hz), 1.84 (quint, 4H, H2, nBu, 3JHH = 7.2 Hz), 1.37 (m, 4H, H3, nBu, 3JHH = 7.2

Hz), 0.96 (t, 6H, Me, 3JHH = 7.2 Hz). 13C{1H} NMR (100.8 MHz, CDCl3): δ 171.6 (C2, Im), 121.6 (C4, Im), 121.3 (C5, Im), 63.0 (NCH2N), 51.8 (C1, nBu), 32.8 (C2, nBu), 19.6 (C3, nBu), 13.6 (Me). L3BuAu2Cl2. This was prepared in the same way as L1BzAu2Cl2 starting from L3BuAg2Br2 (321 mg, 0.48 mmol) and [AuCl(SMe2)] (285 mg, 0.97 mmol). Yield: 301 mg, 0.40 mmol, 84%. Mp: 151−152 °C. Anal. Calcd for C17H28N4Au2Cl2: C, 27.11; H, 3.75; N, 7.44. Found: C, 26.88; H, 3.58; N, 7.69. 1H NMR (400.9 MHz, CDCl3): δ 7.10 (d, 2H, CH, Im, 3JHH = 2.0 Hz), 7.03 (d, 2H, CH, Im, 3JHH = 2.0 Hz), 4.22 (t, 4H, CH2CH2N, 3JHH = 6.8 Hz), 4.20 (t, 4H, H1, nBu, 3 JHH = 7.4 Hz), 2.50 (quint, 2H, CH2CH2N, 3JHH = 6.8 Hz), 1.83 (quint, 4H, H2, nBu, 3JHH = 7.2 Hz), 1.36 (sext, 4H, H3, nBu, 3JHH = 7.2 Hz), 0.96 (t, 6H, Me, 3JHH = 7.2 Hz). 13C{1H} NMR (50.3 MHz, CDCl3): δ 170.6 (C2, Im), 121.6 (CH, Im), 120.0 (CH, Im), 51.5 (C1, nBu), 47.6 (CH2CH2N), 32.9 (C2, nBu), 31.3 (CH2CH2N), 19.7 (C3, nBu), 13.6 (Me). L3MeAu2Cl2. [AuCl(SMe2)] (99 mg, 0.34 mmol) was added to a suspension of L3MeAg2Br2 (98 mg, 0.17 mmol) in acetonitrile (15 mL). The mixture was stirred overnight at room temperature in the dark and filtered. The filtrate was concentrated under vacuum to ca. 1 mL. Addition of Et2O (20 mL) gave a white precipitate, which was filtered off, washed with Et2O (3 × 5 mL), and dried under vacuum. Next, the solid that precipitated in the reaction mixture was stirred with DMSO (7 mL), and the suspension was filtered through Celite. The filtrate was concentrated under reduced pressure, and Et2O (20 mL) was added to precipitate a second crop of the same compound, which was filtered off, washed with Et2O (3 × 5 mL), and dried under vacuum. Overall yield: 66 mg, 0.10 mmol, 61%. Mp: 167 °C dec. Anal. Calcd for C11H16N4Au2Cl2: C, 19.75; H, 2.41; N, 8.37. Found: C, 19.60; H, 2.70; N, 8.33. 1H NMR (400.9 MHz, CDCl3): δ 7.55 (d, 2H, CH, Im, 3 JHH = 1.9 Hz), 7.48 (d, 2H, CH, Im, 3JHH = 1.9 Hz), 4.02 (t, 4H, CH2CH2N, 3JHH = 6.2 Hz), 3.76 (s, 6H, Me), 2.44 (quint, 4H, CH2CH2N, 3JHH = 6.2 Hz). 13C{1H} NMR (75.5 MHz, CDCl3): δ 169.7 (C2, Im), 123.6 (C4, Im), 120.0 (C5, Im), 46.1 (CH2CH2N), 37.6 (Me), 28.8 (CH2CH2N). L5MeAu2Cl2. This was prepared in the same way as L1BzAu2Cl2 starting from L5MeAg2Br2 (482 mg, 0.79 mmol) and [AuCl(SMe2)] (515 mg, 1.75 mmol). Yield: 524 mg, 0.75 mmol, 95%. Mp: 77−78 °C. Anal. Calcd for C13H20N4Au2Cl2: C, 22.40; H, 2.89; N, 8.04. Found: C, 22.21; H, 2.54; N, 7.65. 1H NMR (200.1 MHz, CDCl3): δ 7.09 (d, 2H, CH, Im, 3JHH = 1.9 Hz), 6.99 (d, 2H, CH, Im, 3JHH = 1.9 Hz), 4.17 (t, 4H, CH2CH2CH2N, 3JHH = 6.9 Hz), 3.86 (s, 6H, Me), 1.89 (quint, 4H, CH2CH2CH2N, 3JHH = 6.9 Hz), 1.39 (m, 2H, CH2CH2CH2N). 13 C{1H} NMR (75.5 MHz, CDCl3): δ 170.6 (C2, Im), 122.2 (CH, Im), 120.6 (CH, Im), 50.6 (CH2CH2CH2N), 38.4 (Me), 30.1 (CH2CH2CH2N), 22.9(CH2CH2CH2N). L1Bz(AuCCPh)2. Method A: To a solution of L1BzAu2Cl2 (120 mg, 0.15 mmol) in dry CH2Cl2 (7 mL) was added Tl(acac) (96 mg, 0.32 mmol). The white suspension formed was stirred for 10 min and filtered through Celite. Then, HCCPh (42 mg, 45 μL, 0.38 mmol) was added, and the solution was stirred for 6 h. The reaction mixture was filtered through Celite to remove a small amount of colloidal gold and concentrated under vacuum to ca. 1 mL. Addition of Et2O (30 mL) gave a white precipitate, which was filtered off, washed with Et2O (3 × 5 mL), and dried under vacuum. Yield: 122 mg, 0.13 mmol, 88%. Method B: To a suspension of L1BzAg2Br2 (81 mg, 0.12 mmol) in CH2Cl2 (7 mL) was added [AuCCPh]n (77 mg, 0.26 mmol). The gray suspension was stirred overnight at room temperature in the dark and filtered through Celite. The filtrate was stirred with Na2S2O3·5H2O (0.5 g) for 5 h, filtered through Celite, and concentrated under vacuum to ca. 1 mL. Addition of Et2O (20 mL) gave a white precipitate, which was filtered off, washed with Et2O (3 × 5 mL), and dried under vacuum. Yield: 100 mg, 0.11 mmol, 90%. Mp: 140−142 °C dec. Anal. Calcd for C37H30N4Au2: C, 48.06; H, 3.27; N, 6.06. Found: C, 48.39; H, 3.04; N, 6.17. IR (KBr, cm−1): ν(CC) 2115. 1H NMR (400.9 MHz, CDCl3): δ 7.81 (d, 2H, H5, Im, 3JHH = 1.8 Hz), 7.48 (m, 4H, H2, PhCC), 7.36−7.30 (m, 10H, PhCH2), 7.24−7.16 (m, 6H, H3 and H4, PhCC), 6.86 (d, 2H, H4, Im, 3JHH = 1.9 Hz), 6.58 (s, 2H, NCH2N), 5.40 (s, 4H, PhCH2). 13C{1H} NMR (100.8 MHz, CDCl3): δ 187.8 (C2, Im), 134.3 (C1, PhCH2), 132.3 5421


Organometallics

Article

128.2 (C2, PhCH2), 123.4 (C2, C6H4), 121.4 (C4, Im), 120.3 (C5, Im), 104.0 (br s, CCAu), 55.2 (PhCH2), 47.4 (CH2CH2N), 31.3 (CH2CH2N). L1Bu(AuCCPh)2. This was prepared in the same way as L1Bz(AuCCPh)2. Method A: From L1BuAu2Cl2 (115 mg, 0.16 mmol), Tl(acac) (101 mg, 0.33 mmol), and HCCPh (44 μL, 0.40 mmol). Yield: 75 mg, 0.088 mmol, 55%. Method B: From L1BuAg2Br2 (105 mg, 0.16 mmol) and [AuCCPh]n (98 mg, 0.33 mmol). Yield: 93 mg, 0.11 mmol, 68%. Mp: 144 °C dec. Anal. Calcd for C31H34N4Au2: C, 43.47; H, 4.00; N, 6.54. Found: C, 43.55; H, 4.24; N, 6.73. IR (KBr, cm−1): ν(CC) 2111. 1H NMR (400.9 MHz, CDCl3): δ 7.86 (d, 2H, H5, Im, 3JHH = 2.0 Hz), 7.52−7.50 (m, 4H, H2, Ph), 7.28−7.18 (m, 6H, H3 and H4, Ph), 6.96 (d, 2H, H4, Im, 3 JHH = 2.0 Hz), 6.53 (s, 2H, NCH2N), 4.20 (t, 4H, H1, nBu, 3JHH = 7.2 Hz), 1.78 (m, 4H, H2, nBu), 1.83 (m, 4H, H3, nBu), 0.95 (t, 6H, Me, 3 JHH = 7.2 Hz). 13C{1H} NMR (100.8 MHz, CDCl3): δ 187.5 (C2, Im), 132.3 (C2, Ph), 127.9 (C3, Ph), 127.2 (CCAu), 126.6 (C4, Ph), 125.1 (C1, Ph), 121.6 (C4, Im), 121.0 (C5, Im), 105.5 (C CAu), 62.5 (NCH2N), 51.4 (C1, nBu), 33.0 (C2, nBu), 19.7 (C3, nBu), 13.6 (Me). L1Bu(AuCCtBu)2. This was prepared in the same way as L1Bz(AuCCPh)2. Method A: From L1BuAu2Cl2 (156 mg, 0.22 mmol), Tl(acac) (131 mg, 0.43 mmol), and HCCtBu (68 μL, 0.55 mmol). Yield: 107 mg, 0.13 mmol, 60%. Method B: From L1BuAg2Br2 (99 mg, 0.14 mmol) and [AuCCtBu]n (75 mg, 0.27 mmol). Yield: 67 mg, 0.08 mmol, 59%. Mp: 114−115 °C. Anal. Calcd for C27H42N4Au2: C, 39.71; H, 5.18; N, 6.86. Found: C, 39.51; H, 5.38; N, 6.86. IR (KBr, cm−1): ν(CC) 2112. 1H NMR (400.9 MHz, CDCl3): δ 7.72 (d, 2H, H5, Im, 3JHH = 2.0 Hz), 6.89 (d, 2H, H4, Im, 3 JHH = 2.0 Hz), 6.50 (s, 2H, NCH2N), 4.1 (t, 4H, H1, nBu, 3JHH = 7.2 Hz), 1.78 (m, 4H, H2, nBu), 1.32 (m, 22H, H3, nBu, and tBu), 0.93 (t, 6H, H4, nBu, 3JHH = 7.2 Hz). 13C{1H} NMR (100.8 MHz, CDCl3): δ 188.1 (C2, Im), 121.3 (C4, Im), 120.7 (C5, Im), 115.9 (CCAu), 111.5 (CCAu), 62.4 (NCH2N), 51.2 (C1, nBu), 33.0 (C2, nBu), 32.5 (CMe3), 28.3 (CMe3), 19.7 (C3, nBu), 13.6 (C4, nBu). L3Bu(AuCCPh)2. This was prepared in the same way as L1Bz(AuCCPh)2. Method A: From L3BuAu2Cl2 (141 mg, 0.19 mmol), Tl(acac) (120 mg, 0.38 mmol), and HCCPh (52 μL, 0.48 mmol). Yield: 142 mg, 0.16 mmol, 83%. Method B: From L3BuAg2Br2 (94 mg, 0.14 mmol) and [AuCCPh]n (85 mg, 0.29 mmol). Yield: 97 mg, 0.11 mmol, 77%. Mp: 134−135 °C. Anal. Calcd for C33H38N4Au2·(H2O)0.7: C, 44.18; H, 4.43, N, 6.24. Found: C, 44.09; H, 4.49; N, 6.39. The amount of water was estimated from the elemental analyses and corroborated by integration of the 1H NMR spectrum. IR (KBr, cm−1): ν(CC) 2109. 1H NMR (400.9 MHz, CDCl3): δ 7.50−7.48 (m, 4H, H2, Ph), 7.24−7.16 (m, 6H, H3 and H4, Ph), 7.12 (d, 2H, H5, Im, 3JHH = 1.8 Hz), 6.96 (d, 2H, H4, Im, 3 JHH = 1.8 Hz), 4.25 (t, 4H, CH2CH2N, 3JHH = 7.1 Hz), 4.21 (t, 4H, H1, nBu, 3JHH = 7.4 Hz), 2.54 (quint, 2H, CH2CH2N, 3JHH = 7.1 Hz), 1.82 (m, 4H, H2, nBu), 1.55 (s, 1.4H, H2O), 1.35 (m, 4H, H3, nBu), 0.93 (t, 6H, Me, 3JHH = 7.4 Hz). 13C{1H} NMR (100.8 MHz, CDCl3): δ 186.8 (C2, Im), 132.2 (C2, Ph), 128.2 (CCAu), 127.9 (C3, Ph), 126.3 (C4, Ph), 125.7 (C1, Ph), 121.1 (C4, Im), 120.4 (C5, Im), 105.2 (CCAu), 51.2 (C1, nBu), 47.7 (CH2CH2N), 33.2 (C2, nBu), 32.3 (CH2CH2N), 19.7 (C3, nBu), 13.7 (Me). L3Bu(AuCCtBu)2. This was prepared in the same way as L1Bz(AuCCPh)2. Method A: From L3BuAu2Cl2 (112 mg, 0.15 mmol), Tl(acac) (95 mg, 0.31 mmol), and HCCtBu (46 μL, 0.37 mmol). Yield: 81 mg, 0.096 mmol, 64%. Method B: From L3BuAg2Br2 (112 mg, 0.17 mmol) and [AuCCtBu]n (104 mg, 0.38 mmol). Yield: 72 mg, 0.09 mmol, 53%. Mp: 114 °C dec. Anal. Calcd for C29H46N4Au2: C, 41.24; H, 5.49; N, 6.63. Found: C, 41.25; H, 5.88; N, 6.61. IR (KBr, cm−1): ν(CC) 2109. 1H NMR (400.9 MHz, CDCl3): δ 7.11 (d, 2H, H5, Im, 3JHH = 2.0 Hz), 6.90 (d, 2H, H4, Im, 3 JHH = 2.0 Hz), 4.19 (m, 8H, CH2CH2N and H1, nBu), 2.50 (quint, 4H, CH2CH2N, 3JHH = 7.2 Hz), 1.82−1.74 (m, 4H, H2, nBu), 1.32 (s br, 22H, H3, nBu, and tBu), 0.94 (t, 6H, H4, nBu, 3JHH = 7.3 Hz). 13 C{1H} NMR (100.8 MHz, CDCl3): δ 187.3 (C2, Im), 120.6 (C5, Im), 120.5 (C4, Im), 115.5 (CCAu), 112.2 (CCAu), 51.0 (C1,

(C2, PhCC), 129.2 (C3, PhCH2), 129.0 (C4, PhCH2), 128.2 (C2, PhCH2), 127.9 (C3, PhCC), 127.1 (C1, PhCC), 126.7 (C4, PhCC), 125.1 (CCAu), 121.6 (C4, Im), 121.6 (C5, Im), 105.8 (CCAu), 62.6 (NCH2N), 55.2 (PhCH2). L1Bz(AuCCtBu)2. This was prepared in the same way as 1 L Bz(AuCCPh)2. Method A: From L1BzAu2Cl2 (71 mg, 0.090 mmol), Tl(acac) (57 mg, 0.19 mmol), and HCCtBu (27 μL, 0.22 mmol). Yield: 58 mg, 0.066 mmol, 73%. Method B: From L1BzAg2Br2 (117 mg, 0.17 mmol) and [AuCCtBu]n (92 mg, 0.33 mmol). Yield: 105 mg, 0.12 mmol, 70%. Mp: 195 °C dec. Anal. Calcd for C33H38N4Au2: C, 44.81; H, 4.33; N, 6.33. Found: C, 44.54; H, 4.36; N, 6.26. IR (KBr, cm−1): ν(CC) 2116. 1H NMR (400.9 MHz, CDCl3): δ 7.73 (d, 2H, H5, Im, 3JHH = 2.0 Hz), 7.36−7.25 (m, 10H, Ph), 6.81 (d, 2H, H4, Im, 3JHH = 2.0 Hz), 6.58 (s, 2H, NCH2N), 5.38 (s, 4H, CH2Ph), 1.31 (s, 9H, tBu). 13C{1H} NMR (100.8 MHz, CDCl3): δ 188.4 (C2, Im), 134.5 (C1, Ph), 129.1 (C3, Ph), 128.9 (C4, Ph), 128.1 (C2, Ph), 121.4 (C4, Im), 121.3 (C5, Im), 116.1 (CCAu), 111.3 (CCAu), 62.4 (NCH2N), 55.0 (PhCH2), 32.4 (CMe3), 28.3 (CMe3). L3Bz(AuCCPh)2. Prepared in the same way as L1Bz(AuCCPh)2. Method A: From L3BzAu2Cl2 (127 mg, 0.15 mmol), Tl(acac) (99 mg, 0.33 mmol), and HCCPh (42 μL, 0.39 mmol). Yield: 99 mg, 0.10 mmol, 69%. Method B: From L3BzAg2Br2 (100 mg, 0.14 mmol) and [AuCCPh]n (85 mg, 0.29 mmol). Yield: 83 mg, 0.09 mmol, 62%. Mp: 143−144 °C. Anal. Calcd for C39H34N4Au2: C, 49.17; H, 3.60; N, 5.88. Found: C, 48.74; H, 3.43; N, 5.87. IR (KBr, cm−1): ν(CC) 2105. 1H NMR (400.9 MHz, CDCl3): δ 7.50−7.47 (m, 4H, H2, PhCH2), 7.33−7.18 (m, 16H, Ph), 7.03 (d, 2H, H5, Im, 3JHH = 2.0 Hz), 6.78 (d, 2H, H4, Im, 3JHH = 2.0 Hz), 5.47 (s, 4H, CH2Ph), 4.31 (t, 4H, CH2CH2N, 3JHH = 6.8 Hz), 2.55 (quint, 2H, CH2CH2N, 3JHH = 6.8 Hz). 13C{1H} NMR (110.8 MHz, CDCl3): δ 187.1 (C2, Im), 135.3 (C1, CH2Ph), 132.2 (C2, PhCC), 129.0 (C3, PhCH2), 128.5 (C4, PhCH2), 128.3 (C2, PhCH2), 127.9 (C3, PhCC), 126.4 (C4, PhCC), 125.7 (CCAu), 121.2 (C4, Im), 120.5 (C5, Im), 105.3 (CCAu), 55.0 (PhCH2), 47.5 (CH2CH2N), 31.4 (CH2CH2N); the signal of C1 of PhCC was not detected. L3Bz(AuCCtBu)2. Prepared in the same way as L1Bz(AuC CPh)2. Method A: From L3BzAu2Cl2 (61 mg, 0.074 mmol), Tl(acac) (48 mg, 0.16 mmol), and HCCtBu (23 μL, 0.19 mmol). Yield: 54 mg, 0.059 mmol, 80%. Method B: From L3BzAg2Br2 (138 mg, 0.19 mmol) and [AuCCtBu]n (105 mg, 0.38 mmol). Yield: 102 mg, 0.11 mmol, 59%. Mp: 170 °C dec. Anal. Calcd for: C35H42N4Au2: C, 46.06; H, 4.64; N, 6.14. Found: C, 45.98; H, 5.00; N, 6.21. IR (KBr, cm−1): ν(CC) 2112. 1H NMR (400.9 MHz, CDCl3): δ 7.35−7.25 (m, 10H, Ph), 7.03 (d, 2H, H5, Im, 3JHH = 2.0 Hz), 6.67 (d, 2H, H4, Im, 3 JHH = 2.0 Hz), 5.38 (s, 4H, PhCH2), 4.26 (t, 4H, CH2CH2N, 3JHH = 7.1 Hz), 2.56 (quint, 2H, CH2CH2N, 3JHH = 7.1 Hz), 1.30 (s, 9H, t Bu). 13C{1H} NMR (110.8 MHz, CDCl3): δ 187.6 (C2, Im), 135.3 (C1, Ph), 128.9 (C3, Ph), 128.5 (C4, Ph), 128.1 (C2, Ph), 121.1 (C5, Im), 120.5 (C4, Im), 115.7 (CCAu), 112.0 (CCAu), 54.8 (CH2Ph), 47.9 (CH2CH2N), 32.5 (CMe3), 32.0 (CH2CH2N), 28.3 (CMe3). L3Bz(AuCCC6H4NO2-4)2. Method C: To a solution of L3BzAu2Cl2 (180 mg, 0.22 mmol) in acetone (15 mL) were added K2CO3 (69 mg, 0.50 mmol) and HCCC6H4NO2-4 (65 mg, 0.44 mmol). The reaction mixture was stirred for 24 h, and the solvent was removed under vacuum. The residue was stirred with 20 mL of CH2Cl2. After filtration through Celite, the solution was concentrated under vacuum to ca. 1 mL. Addition of Et2O (20 mL) gave a yellow solid, which was filtered, washed with Et2O (3 × 5 mL), and dried under vacuum. Yield: 208 mg, 0.20 mmol, 91%. Mp: 160 °C dec. Anal. Calcd for C39H32N6Au2O4: C, 44.93; H, 3.09; N, 8.06. Found: C, 44.97; H, 2.80; N, 8.05. IR (KBr, cm−1): ν(CC) 2107. 1H NMR (400.9 MHz, CDCl3): δ 8.13−8.10 (m, 4H, H2, C6H4), 7.57−7.54 (m, 4H, H3, C6H4), 7.37−7.28 (m, 10H, Ph), 7.04 (d, 2H, H5, Im, 3JHH = 1.8 Hz), 6.83 (d, 2H, H4, Im, 3JHH = 1.8 Hz), 5.48 (s, 4H, CH2Ph), 4.31 (t, 4H, CH2CH2N, 3JHH = 6.6 Hz), 2.55 (quint, 2H, CH2CH2N, 3JHH = 6.6 Hz). 13C{1H} NMR (100.8 MHz, CDCl3): δ 186.6 (C2, Im), 145.6 (C1, C6H4), 137.3 (br s, CCAu), 135.0 (C1, PhCH2), 133.0 (C4, C6H4), 132.6 (C3, C6H4), 129.1 (C3, PhCH2), 128.7 (C4, PhCH2), 5422


Organometallics

Article

n

Bu), 47.8 (CH2CH2N), 33.1 (C2, nBu), 32.6 (CMe3), 32.5 (CH2CH2N), 28.3 (CMe3), 19.7 (C3, nBu), 16.7 (C4, nBu). L3Bu(AuCCC6H4NO2-4)2. This was prepared in the same way as 3 L Bz(AuCCC6H4NO2-4)2 (method C) from L3BuAu2Cl2 (55 mg, 0.073 mmol), K2CO3 (44 mg, 0.32 mmol), and HCCC6H4NO2 (24 mg, 0.16 mmol). Yield: 43 mg, 0.05 mmol, 72%. Mp: 164.7 °C dec. Anal. Calcd for C33H36N6Au2O4: C, 40.67; H, 3.72; N, 8.62. Found: C, 40.52; H, 3.61; N, 8.60. IR (KBr, cm−1): ν(CC) 2105. 1H NMR (400.9 MHz, CDCl3): δ 8.14−8.11 (m, 4H, H2, C6H4), 7.58−7.55 (m, 4H, H3, C6H4), 7.10 (d, 2H, H5, Im, 3JHH = 2.0 Hz), 7.00 (d, 2H, H4, Im, 3JHH = 2.0 Hz), 4.26 (t, 4H, CH2CH2N, 3JHH = 6.8 Hz), 4.23 (t, 4H, H1, nBu, 3JHH = 7.2 Hz), 2.53 (quint, 2H, CH2CH2N, 3JHH = 6.8 Hz), 1.84 (m, 4H, H2, nBu), 1.36 (m, 4H, H3, nBu), 0.94 (t, 6H, Me, 3 JHH = 7.2 Hz). 13C{1H} NMR (100.8 MHz, CDCl3): δ 186.2 (C2, Im), 145.6 (C1, C6H4), 137.3 (br s, CCAu), 133.1 (C4, C6H4), 132.6 (C3, C6H4), 123.4 (C2, C6H4), 121.3 (C4, Im), 120.2 (C5, Im), 103.8 (br s, CCAu), 51.3 (C1, nBu), 47.6 (CH2CH2N), 33.1 (C2, n Bu), 32.0 (CH2CH2N), 19.7 (C3, nBu), 13.6 (Me). L3Bu(AuCCSiMe3)2. This was prepared in the same way as L1Bz(AuCCPh)2 (method A) from L3BuAu2Cl2 (104 mg, 0.14 mmol), Tl(acac) (88 mg, 0.29 mmol), and HCCSiMe3 (49 μL, 0.35 mmol). After filtration, Et2O (20 mL) was added to the CH2Cl2 solution, and the resulting suspension was filtered through Celite. The filtrate was concentrated under vacuum to ca. 1 mL. Addition of npentane (30 mL) gave a white precipitate, which was filtered, washed with Et2O (3 × 5 mL), and dried under vacuum. Yield: 53 mg, 0.060 mmol, 43%. Mp: 156−158 °C. Anal. Calcd for C27H46N4Au2Si2: C, 36.99; H, 5.29; N, 6.39. Found: C, 36.75; H, 5.63; N, 6.45. IR (KBr, cm−1): ν(CC) 2051. 1H NMR (300.1 MHz, CDCl3): δ 7.08 (d, 2H, H5, Im, 3JHH = 1.9 Hz), 6.92 (d, 2H, H4, Im, 3JHH = 1.9 Hz), 4.18 (t, 4H, CH2CH2N, 3JHH = 7.1 Hz), 4.16 (t, 4H, H1, nBu, 3JHH = 7.3 Hz), 2.47 (quint, 2H, CH2CH2N, 3JHH = 7.1 Hz), 1.79 (m, 4H, H2, nBu), 1.34 (m, 4H, H3, nBu), 0.94 (t, 6 H, H4, nBu, 3JHH = 7.3 Hz), 0.21 (s, 18H, SiMe3). 13C{1H} NMR (75.5 MHz, CDCl3): δ 186.8 (C2, Im), 147.5 (CCAu), 120.7 (CH, Im), 120.6 (CH, Im), 110.4 (CCAu), 51.1 (C1, nBu), 47.7 (CH2CH2N), 33.2 (C2, nBu), 32.4 (CH2CH2N), 19.7 (C3, nBu), 13.7 (C4, nBu), 1.1 (SiMe3). L3Bu(AuCCC6H4CF3-4)2. This was prepared in the same way as 3 L Bz(AuCCC6H4NO2-4)2 (method C), from L3BuAu2Cl2 (160 mg, 0.21 mmol), K2CO3 (89 mg, 0.64 mmol), and HCCC6H4CF3 (77 μL, 0.47 mmol). Yield: 136 mg, 0.13 mmol, 63%. Mp: 84−86 °C. Anal. Calcd for C35H36N6Au2F6: C, 41.19; H, 3.56; N, 5.49. Found: C, 41.02; H, 3.59; N, 5.54. IR (KBr, cm−1): ν(CC) 2112. 1H NMR (400.9 MHz, CDCl3): δ 7.57−7.55 (m, 4H, H2, C6H4), 7.50−7.48 (m, 4H, H3, C6H4), 7.10 (d, 2H, H5, Im, 3JHH = 1.8 Hz), 6.98 (d, 2H, H4, Im, 3JHH = 1.8 Hz), 4.26 (t, 4H, CH2CH2N, 3JHH = 6.9 Hz), 4.22 (t, 4H, H1, nBu, 3JHH = 7.3 Hz), 2.53 (quint, 2H, CH2CH2N, 3JHH = 6.9 Hz), 1.83 (m, 4H, nBu, H2), 1.35 (m, 4H, H3, nBu), 0.94 (t, 6H, Me, 3 JHH = 7.3 Hz). 13C{1H} NMR (75.5 MHz, CDCl3): δ 186.5 (C2, Im), 132.2 (C3, C6H4), 129.5 (C4, C6H4), 127.9 (q, C1, C6H4, 2JCF = 32.3 Hz), 124.9 (q, C2, C6H4, 3JCF = 3.7 Hz), 124.3 (q, CF3, 1JCF = 272.0 Hz), 121.2 (C4, Im), 120.3 (C5, Im), 103.9 (CCAu), 51.2 (C1, n Bu), 47.6 (CH2CH2N), 33.1 (C2, nBu), 32.1 (CH2CH2N), 19.7 (C3, n Bu), 13.6 (Me). 19F NMR (282.4 MHz, CDCl3): δ −62.4. L3Bu(AuCCC6H4OMe-4)2. This was prepared in the same way as L3Bz(AuCCC6H4NO2-4)2 (method C), from L3BuAu2Cl2 (73 mg, 0.097 mmol), K2CO3 (54 mg, 0.39 mmol), and HCCC6H4OMe (32 mg, 0.24 mmol). Yield: 82 mg, 0.087 mmol, 89%. Mp: 90−92 °C. Anal. Calcd for C35H42N4Au2O2: C, 44.50; H, 4.48; N, 5.93. Found: C, 44.24; H, 4.88; N, 5.90. IR (KBr, cm−1): ν(CC) 2109. 1H NMR (400.9 MHz, CDCl3): δ 7.45−7.41 (m, 4H, H3, C6H4), 7.11 (d, 2H, H5, Im, 3JHH = 1.8 Hz), 6.95 (d, 2H, H4, Im, 3JHH = 1.8 Hz), 6.81− 6.77 (m, 4H, H2, C6H4), 4.25 (t, 4H, CH2CH2N, 3JHH = 6.8 Hz), 4.20 (t, 4H, H1, nBu, 3JHH = 7.3 Hz), 3.79 (s, 6H, OMe), 2.53 (quint, 2H, CH2CH2N, 3JHH = 6.8 Hz), 1.81 (m, 4H, H2, nBu), 1.34 (m, 4H, H3, n Bu), 0.93 (t, 6H, H4, nBu, 3JHH = 7.3 Hz). 13C{1H} NMR (75.5 MHz, CDCl3): δ 186.7 (C2, Im), 158.1 (C1, C6H4), 133.3 (C3, C6H4), 126.2 (br s, CCAu), 120.9 (C4, Im), 120.4 (C5, Im), 117.9 (C4, C6H4), 113.4 (C2, C6H4), 104.9 (br s, CCAu), 55.1 (OMe), 51.1 (C1,

n

Bu), 47.7 (CH2CH2N), 33.1 (C2, nBu), 32.3 (CH2CH2N), 19.7 (C3, Bu), 13.6 (C4, nBu). L3Bu(AuCCPyl)2. This was prepared in the same way as L3Bz(AuCCC6H4NO2-4)2 (method C), from L3BuAu2Cl2 (91 mg, 0.12 mmol), K2CO3 (44 mg, 0.32 mmol), and 3-ethynylpyridine (29 mg, 0.28 mmol). Yield: 101 mg, 0.11 mmol, 95%. Mp: 63−64 °C. Anal. Calcd for C31H36N6Au2: C, 42.00; H, 4.09; N, 9.48. Found: C, 41.81; H, 4.25; N, 9.48. IR (KBr, cm−1): ν(CC) 2112. 1H NMR (400.9 MHz, CDCl3): δ 8.72 (dd, 2H, H2, Py, 4JHH = 2.0 and 0.8 Hz), 8.40 (dd, 2H, H6, Py, 3JHH = 4.8 Hz, 4JHH = 1.6 Hz), 7.74 (dt, 2H, H4, Py, 3JHH = 8.0 Hz, 4JHH = 1.6 Hz), 7.18 (m, 2H, H5, Py), 7.11 (d, 2H, H5, Im, 3JHH = 2.0 Hz), 6.98 (d, 2H, H4, Im, 3JHH = 2.0 Hz), 4.26 (t, 4H, CH2CH2N, 3JHH = 6.9 Hz), 4.23 (t, 4H, H1, nBu, 3JHH = 7.3 Hz), 2.54 (quint, 2H, CH2CH2N, 3JHH = 6.9 Hz), 1.83 (m, 4H, H2, nBu), 1.35 (m, 4H, H3, nBu), 0.94 (t, 6H, Me, 3JHH = 7.3 Hz). 13C{1H} NMR (75.5 MHz, CDCl3): δ 186.3 (C2, Im), 153.0 (C2, Py), 146.6 (C6, Py), 138.8 (C4, Py), 132.7 (CCAu), 122.7 (C5, Py), 121.2 (C4, Im), 120.3 (C5, Im), 101.5 (CCAu), 51.2 (C1, nBu), 47.6 (CH2CH2N), 33.1 (C2, nBu), 32.1 (CH2CH2N), 19.7 (C3, nBu), 13.6 (Me); the signal of C3 of Py was not detected. L3Me(AuCCBpyl)2. This was prepared in the same way as L3Bz(AuCCC6H4NO2-4)2 (method C), from L3MeAu2Cl2 (104 mg, 0.16 mmol), K2CO3 (107 mg, 0.78 mmol), and HCCBpyl (66 mg, 0.37 mmol). Yield: 120 mg, 0.12 mol, 77%. Mp: 165 °C dec. Anal. Calcd for C35H30N8Au2·H2O: C, 43.13; H, 3.31; N, 11.50. Found: C, 43.15; H, 3.03; N, 11.50. The amount of water was estimated from the elemental analyses and corroborated by integration of the 1H NMR spectrum. IR (KBr, cm−1): ν(CC) 2107. 1H NMR (400.9 MHz, CDCl3): δ 8.77 (dd, 2H, H6, Bpyl, 4JHH = 2.0 Hz, 5JHH = 0.8 Hz), 8.67 (ddd, 2H, H6′, Bpyl, 3JHH = 4.8 Hz, 4JHH = 1.6 Hz, 5JHH = 0.8 Hz), 8.36 (dt, 2H, H3, Bpyl, 3JHH = 8.0 Hz, 4JHH = 5JHH = 1.2 Hz), 8.30 (dd, 2H, H3′, Bpyl, 3JHH = 8.4 Hz, 5JHH = 0.8 Hz), 7.86 (dd, 2H, H4, Bpyl, 3 JHH = 8.4 Hz, 4JHH = 2.0 Hz), 7.80 (td, 2H, H4′, Bpyl, 3JHH = 8.0 Hz, 4 JHH = 1.6 Hz), 7.30−7.27 (m, 2H, H5′, Bpyl), 7.09 (d, 2H, H5, Im, 3 JHH = 2.0 Hz), 7.01 (d, 2H, H4, Im, 3JHH = 2.0 Hz), 4.26 (t, 4H, CH2CH2N, 3JHH = 6.8 Hz), 3.96 (s, 6H, Me), 2.49 (quint, 2H, CH2CH2N, 3JHH = 6.8 Hz), 1.58 (s, 2H, H2O). 13C{1H} NMR (75.5 MHz, CDCl3): δ 187.2 (C2, Im), 156.0 (C2′, Bpyl), 152.9 (C2, Bpyl), 152.3 (C6, Bpyl), 149.2 (C6′, Bpyl), 139.7 (C4, Bpyl), 136.8 (C4′, Bpyl), 134.2 (br s, CCAu), 123.4 (C5′, Bpyl), 123.0 (C4, Im), 122.9 (C5, Bpyl), 121.0 (C3′, Bpyl), 120.2 (C3, Bpyl), 119.7 (C5, Im), 102.0 (br s, CCAu), 46.9 (CH2CH2N), 38.2 (Me), 31.1 (CH2CH2N). L5Me(AuCCPh)2. This was prepared in the same way as 1 L Bz(AuCCPh)2. Method A: From L5MeAu2Cl2 (141 mg, 0.20 mmol), Tl(acac) (129 mg, 0.43 mmol), and HCCPh (56 μL, 0.51 mmol). Yield: 142 mg, 0.17 mmol, 89%. Method B: From L5MeAg2Br2 (82 mg, 0.15 mmol) and [AuCCPh]n (90 mg, 0.30 mmol). Yield: 66 mg, 0.08 mmol, 53%. Mp: 92−93 °C. Anal. Calcd for C29H30N4Au2: 42.04; H, 3.65; N, 6.76. Found: C, 41.99; H, 3.78; N, 6.87. IR (KBr, cm−1): ν(CC) 2111. 1H NMR (300.1 MHz, CDCl3): δ 7.50−7.47 (m, 4 H, Ph), 7.26−7.19 (m, 6 H, Ph), 7.16 (d, 2H, H5, Im, 3JHH = 1.8 Hz), 6.83 (d, 2H, H4, Im, 3JHH = 1.8 Hz), 4.20 (t, 4H, CH2CH2CH2N, 3 JHH = 7.1 Hz), 3.85 (s, 6H, Me), 1.94 (quint, 4H, CH2CH2CH2N, 3 JHH = 7.2 Hz), 1.40 (m, 2H, CH2CH2CH2N). 13C{1H} NMR (75.5 MHz, CDCl3): δ 187.0 (C2, Im), 132.2 (C2, Ph), 128.7 (br s, C CAu), 127.8 (C3, Ph), 126.3 (C4, Ph), 125.7 (C1, Ph), 122.0 (C4, Im), 120.7 (C5, Im), 105.3 (br s, CCAu), 50.3 (CH2CH2CH2N), 38.0 (Me), 30.4 (CH2CH2CH2N), 22.6 (CH2CH2CH2N). L5Me(AuCCtBu)2. This was prepared in the same way as L1Bz(AuCCPh)2 (method A) from L5MeAu2Cl2 (134 mg, 0.19 mmol), Tl(acac) (123 mg, 0.41 mmol), and HCCtBu (59 μL, 0.48 mmol). Yield: 124 mg, 0.17 mmol, 83%. Mp: 124−126 °C. Anal. Calcd for C25H38N4Au2: C, 38.08; H, 4.86; N, 7.11. Found: C, 37.80; H, 4.77; N, 7.03. IR (KBr, cm−1): ν(CC) 2078. 1H NMR (400.9 MHz, CDCl3): δ 7.05 (d, 2H, H5, Im, 3JHH = 2.0 Hz), 6.86 (d, 2H, H4, Im, 3 JHH = 2.0 Hz), 4.08 (t, 4H, CH2CH2CH2N, 3JHH = 6.7 Hz), 3.75 (s, 6H, MeN), 1.78 (quint, 4H, CH2CH2CH2N, 3JHH = 7.3 Hz), 1.23 (m and s, 20H, CH2CH2CH2N and tBu). 13C{1H} NMR (100.8 MHz, CDCl3): δ 187.6 (C2, Im), 121.9 (C4, Im), 120.6 (C5, Im), 115.4 (br n

5423


Organometallics

Article

[Au(CCBpyl)(CNtBu)]. tert-Butylisocyanide (31 mg, 0.37 mmol) was added to a suspension of [Au(CCBpyl)]n (141 mg, 0.37 mmol) in CH2Cl2 (10 mL). The mixture was stirred for 45 min. The solution was concentrated under vacuum to ca. 1 mL. Addition of Et2O (30 mL) gave a beige-colored precipitate, which was filtered off, washed with Et2O (3 × 5 mL), and dried under vacuum. Yield: 129 mg, 0.28 mmol, 76%. Mp: 139−141 °C. Anal. Calcd for C17H16N3Au: C, 44.46; H, 3.51; N, 9.15. Found: C, 44.31; H, 3.45; N, 8.96. IR (KBr, cm−1): ν(CN) 2231, ν(CC) 2127. 1H NMR (400.9 MHz, CDCl3): δ 8.74 (dd, 2H, H6, Bpyl, 4JHH = 2.0 Hz, 5JHH = 0.8 Hz), 8.66 (ddd, 2H, H6′, Bpyl, 3JHH = 4.8 Hz, 4JHH = 1.8, 5JHH = 0.9 Hz), 8.36 (dt, 2H, H3′, Bpyl, 3JHH = 8.0 Hz, 4JHH = 5JHH = 1.1 Hz), 8.29 (dd, 2H, H3, Bpyl, 3 JHH = 7.4 Hz, 5JHH = 0.84 Hz), 7.84 (dd, 2H, H4, Bpyl, 3JHH = 8.2 Hz, 4 JHH = 2.1 Hz), 7.80 (td, 2H, H4′, Bpyl, 3JHH = 7.7 Hz, 4JHH = 1.8 Hz), 7.30−7.26 (m, 2H, H5′, Bpyl), 1.55 (s, 9H, Me). 13C{1H} NMR (75.5 MHz, CDCl3): δ 155.8, 153.4 (C2 and C2′, Bpyl), 152.6 (C6, Bpyl), 149.1 (C6′, Bpyl), 140.1 (C4, Bpyl), 136.8 (C4′, Bpyl), 127.5 (C CAu), 123.5 (C5′, Bpyl), 121.8 (C5, Bpyl), 121.1 (C3′, Bpyl), 120.1 (C3, Bpyl), 100.1 (br s, CCAu), 58.7 (CMe3), 29.8 (CMe3); the signal of AuCN was not detected. X-ray Crystallography. Crystals of L3Bu(AuCCPh)2 and 3 L *Au2Cl2 were obtained by liquid diffusion between a CHCl3 solution and Et2O. Both were measured on a Bruker Smart APEX machine at 100 K, using monochromated Mo Kα radiation (λ = 0.71073 Å) in ω-scan mode. The structures were solved by direct methods and were refined anisotropically on F2. The nitrogen-bound hydrogen atoms of L3*Au2Cl2 were refined freely with DFIX. The ordered methyl groups were refined using rigid groups, and the other hydrogen atoms were refined using a riding mode. Special features: In compound L3Bu(AuCCPh)2 one nBu group is disordered over two positions with a ca. 53:47% occupancy distribution.

s, CCAu), 112.7 (br s, CCAu), 50.2 (CH2CH2CH2N), 38.0 (MeN), 32.6 (CMe3), 30.4 (CH2CH2CH2N), 28.3 (CMe3), 22.6 (CH2CH2CH2N). L5Me(AuCCBpyl)2. This was prepared in the same way as L3Bz(AuCCC6H4NO2-4)2 (method C), from L5MeAu2Cl2 (77 mg, 0.11 mmol), K2CO3 (46 mg, 0.33 mmol), and HCCBpyl (49 mg, 0.27 mmol). Yield: 103 mg, 0.10 mmol, 95%. Mp: 162 °C dec. Anal. Calcd for C37H34N8Au2: C, 45.13; H, 3.48; N, 11.38. Found: C, 44.80; H, 3.13; N, 11.18. IR (KBr, cm−1): ν(CC) 2111. 1H NMR (300.1 MHz, CDCl3): δ 7.78 (dd, 2H, H6, Bpyl, 4JHH = 2.0 Hz, 5JHH = 0.7 Hz), 8.67 (ddd, 2H, H6′, Bpyl, 3JHH = 4.8 Hz, 4JHH = 1.8 Hz, 5JHH = 0.9 Hz), 8.36 (dt, 2H, H3′, Bpyl, 3JHH = 7.8 Hz, 4JHH = 5JHH = 1.2 Hz), 8.29 (dd, 2H, H3, Bpyl, 3JHH = 8.4 Hz, 5JHH = 0.9 Hz), 7.85 (dd, 2H, H4, Bpyl, 3JHH = 8.4 Hz, 4JHH = 2.1 Hz), 7.80 (td, 2H, H4′, Bpyl, 3JHH = 7.5 Hz, 4JHH = 1.8 Hz), 7.30−7.26 (m, 2H, H5′, Bpyl), 7.14 (d, 2H, H5, Im, 3JHH = 2.1 Hz), 6.89 (d, 2H, H4, Im, 3JHH = 1.8 Hz), 4.22 (t, 4H, CH2CH2CH2N, 3JHH = 7.2 Hz), 3.87 (s, 6H, Me), 1.9 (quint, 4H, CH2CH2CH2N, 3JHH = 7.2 Hz), 1.42 (m, 2H, CH2CH2CH2N). 13 C{1H} NMR (75.5 MHz, CDCl3): δ 186.5 (C2, Im), 156.0 (C2′, Bpyl), 152.9 (C2, Bpyl), 152.4 (C6, Bpyl), 149.2 (C6′, Bpyl), 139.8 (C4, Bpyl), 136.8 (C4′, Bpyl), 134.8 (br s, CCAu), 123.4 (C5′, Bpyl), 122.8 (C5, Bpyl), 122.1 (C4, Im), 121.0 (C3′, Bpyl), 120.7 (C5, Im), 120.1 (C3, Bpyl), 102.0 (br s, CCAu), 50.4 (CH2CH2CH2N), 38.0 (Me), 30.4 (CH2CH2CH2N), 27.7 (CH2CH2CH2N). LMeAuCCSiMe3. To a solution of [AuCl(Im-Me2)] (84 mg, 0.26 mmol) in dry CH2Cl2 (10 mL) was added Tl(acac) (80 mg, 0.26 mmol). The white suspension was stirred for 10 min and filtered through Celite. Then, HCCSiMe3 (36 μL, 0.26 mmol) was added, and the solution was stirred for 3 h. The reaction mixture was concentrated under vacuum to ca. 1 mL. Addition of n-hexane (30 mL) gave a white precipitate, which was filtered off, washed with nhexane (3 × 5 mL), and dried under vacuum. Yield: 68 mg, 0.17 mmol, 65%. Mp: 142 °C dec. Anal. Calcd for C10H17N2AuSi: C, 30.77; H, 4.39; N, 7.18. Found: C, 30.70; H, 4.27; N, 7.10. IR (KBr, cm−1): ν(CC) 2057. 1H NMR (400.9 MHz, CDCl3): δ 6.87 (s, 2H, CH), 3.80 (s, 6H, Me), 0.20 (s, 9H, SiMe3). 13C{1H} NMR (100.8 MHz, CDCl3): δ 188.1 (C2, Im), 147.4 (s, CCAu), 121.8 (CH), 110.8 (s, CCAu), 38.0 (Me), 1.2 (SiMe3). LBzAuCCtBu. To a suspension of LBzAgBr (128 mg, 0.29 mmol) in CH2Cl2 (12 mL) was added [AuCCtBu]n (82 mg, 0.29 mmol). The gray suspension was stirred overnight at room temperature in the dark. It was filtered through Celite and stirred for 5 h with excess Na2S2O3·5H2O (500 mg, 2.01 mmol). Then, it was filtered, and the filtrate was concentrated under vacuum to ca. 1 mL. Addition of nhexane (30 mL) gave a white precipitate, which was filtered off, washed with n-hexane (3 × 5 mL), and dried under vacuum. Yield: 95 mg, 0.18 mmol, 62%. Mp: 156−158 °C dec. Anal. Calcd for C23H25N2Au: C, 52,48; H, 4,79; N, 5.32. Found: C, 52.20; H, 4.76; N, 5.42. IR (Nujol, cm−1): ν(CC) 2020. 1H NMR (400.9 MHz, CDCl3): δ 7.37−7.26 (m, 10H, Ph), 6.76 (s, 2H, H4 and H5), 5.44 (s, 4H, CH2), 1.32 (s, tBu). 13C{1H} NMR (75.5 MHz, CDCl3): δ 188.1 (C2, Im), 135.5 (C1, Ph), 129.1 (C3, Ph), 128.7 (C4, Ph), 128.2 (C2, Ph), 120.8 (CH, Im), 116.0 (br s, CCAu), 111.6 (br s, CCAu), 54.9 (CH2), 32.7 (CMe3), 28.5 (CMe3). L3*Au2Cl2. To a solution of [AuCl(SMe2)] (258 mg, 0.88 mmol) in dry CH2Cl2 (7 mL) were added tert-butylisocyanide (73 mg, 0.88 mmol) and N,N′-diethyl-1,3-propanediamine (70 μL, 0.44 mmol). The solution was stirred at 60 °C for 3 days. The reaction mixture was filtered through Celite and concentrated under vacuum to ca. 1 mL. Addition of methanol (30 mL) gave a white precipitate, which was filtered off, washed with methanol (3 × 5 mL), and dried under vacuum. Yield: 230 mg, 0.30 mmol, 69%. Mp: 147 °C dec. Anal. Calcd for C17H36N4Au2Cl2: C, 26.82; H, 4.77; N, 7.36. Found: C, 26.84; H, 4.69; N, 7.41. 1H NMR (400.9 MHz, CDCl3): δ 6.06 (s, 2H, NHtBu), 4.11 (t, 4H, CH2CH2N, 3JHH = 7.2), 3.45 (q, 4H, CH3CH2N, 3JHH = 7.2 Hz), 1.98 (quint, 2H, CH2CH2N, 3JHH = 7.2 Hz), 1.65 (s, 18H, t Bu), 1.18 (t, 6 H, CH3CH2N, 3JHH = 7.2 Hz). 13C{1H} NMR (100.8 MHz, CDCl3): δ 190.1 (NCN), 57.1 (CH2CH2N), 54.6 (CMe3), 41.3 (CH3CH2N), 31.8 (CMe3), 28.8 (CH2CH2N), 11.5 (CH3CH2N).

■

ASSOCIATED CONTENT

S Supporting Information *

Crystallographic information in CIF format, supplementary emission spectra, and table of crystallographic data. This material is available free of charge via the Internet at http:// pubs.acs.org.

■

AUTHOR INFORMATION

Corresponding Author

*E-mail: [email protected], [email protected], http://www.um.es/gqo/. Notes

The authors declare no competing financial interest.

■

ACKNOWLEDGMENTS We thank the Spanish Ministerio de Ciencia e Innovación (grant CTQ2007-60808/BQU, with FEDER support) and Fundación Séneca (grant 04539/GERM/06) for financial support.

■

REFERENCES

(1) Lima, J. C.; Rodriguez, L. Chem. Soc. Rev. 2011, 40, 5442. (2) Schmidbaur, H.; Schier, A. Chem. Soc. Rev. 2008, 37, 1931. Schmidbaur, H.; Schier, A. Chem. Soc. Rev. 2012, 41, 370. Bardají, M.; Laguna, A. J. Chem. Educ. 1999, 76, 201. (3) Vicente, J.; Chicote, M. T.; Á lvarez-Falcón, M. M.; Fox, M. A.; Bautista, D. Organometallics 2003, 22, 4792. (4) Puddephatt, R. J. Chem. Soc. Rev. 2008, 37, 2012. (5) Lu, W.; Kwok, W.-M.; Ma, C.; Chan, C. T.-L.; Zhu, M.-X.; Che, C.-M. J. Am. Chem. Soc. 2011, 133, 14120. (6) Vicente, J.; Chicote, M. T.; Á lvarez-Falcón, M. M.; Jones, P. G. Organometallics 2005, 24, 2764. (7) Coco, S.; Cordovilla, C.; Dominguez, C.; Espinet, P. Dalton Trans. 2008, 6894.

5424


Organometallics

Article

Dalton Trans. 1994, 1867. Che, C. M.; Yip, H. K.; Lo, W. C.; Peng, S. M. Polyhedron 1994, 13, 887. (32) McArdle, C. P.; Van, S.; Jennings, M. C.; Puddephatt, R. J. J. Am. Chem. Soc. 2002, 124, 3959. Koshevoy, I. O.; Lin, C.-L.; Karttunen, A. J.; Haukka, M.; Shih, C.-W.; Chou, P.-T.; Tunik, S. P.; Pakkanen, T. A. Chem. Commun. 2011, 47, 5533. (33) Xiao, H.; Cheung, K. K.; Che, C. M. J. Chem. Soc., Dalton Trans. 1996, 3699. (34) Lin, J. C. Y.; Huang, R. T. W.; Lee, C. S.; Bhattacharyya, A.; Hwang, W. S.; Lin, I. J. B. Chem. Rev. 2009, 109, 3561. Mata, J. A.; Poyatos, M.; Peris, E. Coord. Chem. Rev. 2007, 251, 841. (35) Lin, I. J. B.; Vasam, C. S. Coord. Chem. Rev. 2007, 251, 642. (36) Vicente, J.; Chicote, M. T.; Saura-Llamas, I.; Lagunas, M. C. J. Chem. Soc., Chem. Commun. 1992, 915. Vicente, J.; Chicote, M. T. Coord. Chem. Rev. 1999, 195, 1143. Vicente, J.; Chicote, M. T.; Abrisqueta, M. D. J. Chem. Soc., Dalton Trans. 1995, 497. (37) Lee, H. M.; Lu, C. Y.; Chen, C. Y.; Chen, W. L.; Lin, H. C.; Chiu, P. L.; Cheng, P. Y. Tetrahedron 2004, 60, 5807. (38) Hsiao, T.-H.; Wu, T.-L.; Chatterjee, S.; Chiu, C.-Y.; Lee, H. M.; Bettucci, L.; Bianchini, C.; Oberhauser, W. J. Organomet. Chem. 2009, 694, 4014. (39) Lee, M.; Niu, Z.; Slebodnick, C.; Gibson, H. W. J. Phys. Chem. B 2010, 114, 7312. (40) Anderson, J. L.; Ding, R.; Ellern, A.; Armstrong, D. W. J. Am. Chem. Soc. 2004, 127, 593. (41) Ahrens, S.; Zeller, A.; Taige, M.; Strassner, T. Organometallics 2006, 25, 5409. (42) Nielsen, D. J.; Cavell, K. J.; Skelton, B. W.; White, A. H. Organometallics 2006, 25, 4850. (43) Paulose, T. A. P.; Wu, S.-C.; Olson, J. A.; Chau, T.; Theaker, N.; Hassler, M.; Quail, J. W.; Foley, S. R. Dalton Trans. 2012, 41, 251. (44) Manojlovic-Muir, L.; Henderson, A. N.; Treurnicht, I.; Puddephatt, R. J. Organometallics 1989, 8, 2055. McArdle, C. P.; Irwin, M. J.; Jennings, M. C.; Puddephatt, R. J. Angew. Chem., Int. Ed. 1999, 38, 3376. McArdle, C. P.; Vittal, J. J.; Puddephatt, R. J. Angew. Chem., Int. Ed. 2000, 39, 3819. MacDonald, M. A.; Puddephatt, R. J.; Yap, G. P. A. Organometallics 2000, 19, 2194. McArdle, C. P.; Jennings, M. C.; Vittal, J. J.; Puddephatt, R. J. Chem. Eur. J. 2001, 7, 3572. McArdle, C. P.; Irwin, M. J.; Jennings, M. C.; Vittal, J. J.; Puddephatt, R. J. Chem. Eur. J. 2002, 8, 723. Hunks, W. J.; Lapierre, J.; Jenkins, H. A.; Puddephatt, R. J. J. Chem. Soc., Dalton Trans. 2002, 2885. Mohr, F.; Eisler, D. J.; McArdle, C. P.; Atieh, K.; Jennings, M. C.; Puddephatt, R. J. J. Organomet. Chem. 2003, 670, 27. Mohr, F.; Jennings, M. C.; Puddephatt, R. J. Eur. J. Inorg. Chem. 2003, 217. Mohr, F.; Puddephatt, R. J. J. Organomet. Chem. 2004, 689, 374. Hunks, W. J.; Jennings, M. C.; Puddephatt, R. J. Z. Naturforsch., B 2004, 59, 1488. Ferguson, G.; Gallager, J. F.; Kelleher, A.-M.; Spalding, T. R.; Deeney, F. T. J. Organomet. Chem. 2005, 690, 2888. Habermehl, N. C.; Jennings, M. C.; McArdle, C. P.; Mohr, F.; Puddephatt, R. J. Organometallics 2005, 24, 5004. Habermehl, N. C.; Eisler, D. J.; Kirby, C. W.; Yue, N. L. S.; Puddephatt, R. J. Organometallics 2006, 25, 2921. Ferguson, G.; Gallagher, J. F.; Kennedy, J. D.; Kelleher, A.-M.; Spalding, T. R. Dalton Trans. 2006, 2133. Burchell, T. J.; Jennings, M. C.; Puddephatt, R. J. Inorg. Chim. Acta 2006, 359, 2812. Koshevoy, I. O.; Koskinen, L.; Haukka, M.; Tunik, S. P.; Serdobintsev, P. Y.; Melnikov, A. S.; Pakkanen, T. A. Angew. Chem., Int. Ed. 2008, 47, 3942. Packheiser, R.; Ecorchard, P.; Rueffer, T.; Lang, H. Chem. Eur. J. 2008, 14, 4948. Koshevoy, I. O.; Smirnova, E. S.; Domenech, A.; Karttunen, A. J.; Haukka, M.; Tunik, S. P.; Pakkanen, T. A. Dalton Trans. 2009, 8392. Koshevoy, I. O.; Lin, Y.-C.; Karttunen, A. J.; Chou, P.-T.; Vainiotalo, P.; Tunik, S. P.; Haukka, M.; Pakkanen, T. A. Inorg. Chem. 2009, 48, 2094. Constable, E. C.; Housecroft, C. E.; Kocik, M. K.; Zampese, J. A. Polyhedron 2011, 30, 2704. Koshevoy, I. O.; Lin, C.-L.; Karttunen, A. J.; Janis, J.; Haukka, M.; Tunik, S. P.; Chou, P.-T.; Pakkanen, T. A. Inorg. Chem. 2011, 50, 2395. Koshevoy, I. O.; Lin, C.-L.; Karttunen, A. J.; Jaenis, J.; Haukka, M.; Tunik, S. P.; Chou, P.-T.; Pakkanen, T. A. Chem. Eur. J. 2011, 17, 11456. Li, X.-L.; Tan, M.; Zhang, K.-J.; Yang, B.; Chen, J.; Ai, Y.-B. Inorg. Chem. 2012, 51, 109.

(8) Ferrer, M.; Mounir, M.; Rodriguez, L.; Rossell, O.; Coco, S.; Gómez-Sal, P.; Martín, A. J. Organomet. Chem. 2005, 690, 2200. (9) Vicente, J.; Chicote, M. T.; Á lvarez-Falcon, M. M.; Jones, P. G. Chem. Commun. 2004, 2658. (10) Bruce, M. I.; Hall, B. C.; Skelton, B. W.; Smith, M. E.; White, A. H. J. Chem. Soc., Dalton Trans. 2002, 995. Tang, H.-S.; Zhu, N.; Yam, V. W.-W. Organometallics 2007, 26, 22. (11) Vicente, J.; Gil-Rubio, J.; Barquero, N.; Cámara, V.; Masciocchi, N. Chem. Commun. 2010, 46, 1053. (12) Cordovilla, C.; Coco, S.; Espinet, P.; Donnio, B. J. Am. Chem. Soc. 2010, 132, 1424. (13) Yam, V. W.-W.; Wong, K. M.-C. Chem. Commun. 2011, 47, 11579. Yam, V. W.-W.; Cheng, E. C.-C. Chem. Soc. Rev. 2008, 37, 1806. (14) He, X.; Cheng, E. C.-C.; Zhu, N.; Yam, V. W.-W. Chem. Commun. 2009, 4016. (15) He, X.; Lam, W. H.; Zhu, N.; Yam, V. W.-W. Chem. Eur. J. 2009, 15, 8842. (16) Meng, X.; Moriuchi, T.; Kawahata, M.; Yamaguchi, K.; Hirao, T. Chem. Commun. 2011, 47, 4682. (17) Ikeda, S.; Nagashima, H. Patent JP2008120942A, 2008; CAplus AN 2008:639422. Fujimura, H.; Fukunaga, K.; Honma, T.; Machida, T. Patent JP2006290750A, 2006; CAplus AN 2006:1117732. (18) Fujimura, O.; Fukunaga, K.; Honma, T.; Machida, T. Patent JP2008179550A, 2008; CAplus AN 2008:939405. Fujimura, O.; Fukunaga, K.; Honma, T.; Machida, T. Patent JP2010037244A, 2010; CAplus AN 2010:204975. Fujimura, O.; Fukunaga, K.; Honma, T.; Machida, T. Patent WO2009113646A1, 2009; CAplus AN 2009:1137833. Fujimura, O.; Fukunaga, K.; Honma, T.; Machida, T. Patent WO2008050733A1, 2008; CAplus AN 2008:529250. Fujimura, O.; Fukunaga, K.; Honma, T.; Machida, T. Patent WO2007139001A1, 2007; CAplus AN 2007:1395985. Fujimura, O.; Fukunaga, K.; Honma, T.; Machida, T.; Takahashi, T. Patent WO2006080515A1, 2006; CAplus AN 2006:768313. (19) Vicente, J.; Chicote, M. T.; Á lvarez-Falcón, M. M.; Jones, P. G. Organometallics 2005, 24, 5956. (20) Vicente, J.; Chicote, M. T.; Á lvarez-Falcón, M. M.; Jones, P. G. Organometallics 2005, 24, 4666. (21) Vicente, J.; Chicote, M. T.; Abrisqueta, M. D.; de Arellano, M. C. R.; Jones, P. G.; Humphrey, M. G.; Cifuentes, M. P.; Samoc, M.; Luther-Davies, B. Organometallics 2000, 19, 2968. (22) Vicente, J.; Chicote, M. T.; Abrisqueta, M. D.; Jones, P. G. Organometallics 1997, 16, 5628. (23) Wang, H. M. J.; Chen, C. Y. L.; Lin, I. J. B. Organometallics 1999, 18, 1216. (24) Singh, S.; Kumar, S. S.; Jancik, V.; Roesky, H. W.; Schmidt, H.G.; Noltemeyer, M. Eur. J. Inorg. Chem. 2005, 2005, 3057. (25) Gao, L.; Partyka, D. V.; Updegraff, J. B.; Deligonul, N.; Gray, T. G. Eur. J. Inorg. Chem. 2009, 2009, 2711. (26) Fortman, G. C.; Poater, A.; Levell, J. W.; Gaillard, S.; Slawin, A. M. Z.; Samuel, I. D. W.; Cavallo, L.; Nolan, S. P. Dalton Trans. 2010, 39, 10382. (27) Konkolewicz, D.; Gaillard, S.; West, A. G.; Cheng, Y. Y.; GrayWeale, A.; Schmidt, T. W.; Nolan, S. P.; Perrier, S. Organometallics 2011, 30, 1315. (28) Chow, A. L.-F.; So, M.-H.; Lu, W.; Zhu, N.; Che, C.-M. Chem. Asian J. 2011, 6, 544. (29) Manbeck, G. F.; Kohler, M. C.; Porter, M. R.; Stockland, R. A., Jr. Dalton Trans. 2011, 40, 12595. (30) Horvath, U. E. I.; McKenzie, J. M.; Cronje, S.; Raubenheimer, H. G.; Barbour, L. J. Chem. Commun. 2009, 6598. Hashmi, A. S. K.; Braun, I.; Rudolph, M.; Rominger, F. Organometallics 2012, 31, 644. (31) Yam, V. W. W.; Cheung, K. L.; Yip, S. K.; Cheung, K. K. J. Organomet. Chem. 2003, 681, 196. Yam, V. W. W.; Choi, S. W. K.; Cheung, K. K. Organometallics 1996, 15, 1734. Yam, V. W. W.; Choi, S. W. K.; Cheung, K. K. J. Chem. Soc., Dalton Trans. 1996, 3411. Yam, V. W. W.; Choi, S. W. K. J. Chem. Soc., Dalton Trans. 1996, 4227. Irwin, M. J.; Vittal, J. J.; Puddephatt, R. J. Organometallics 1997, 16, 3541. Hong, X.; Cheung, K. K.; Guo, C. X.; Che, C. M. J. Chem. Soc., 5425


Organometallics

Article

(45) Vicente, J.; Chicote, M. T.; Á lvarez-Falcón, M. M.; Abrisqueta, M. D.; Hernández, F. J.; Jones, P. G. Inorg. Chim. Acta 2003, 347, 67. (46) Vicente, J.; Chicote, M.-T.; Á lvarez-Falcón, M. M.; Bautista, D. Organometallics 2004, 23, 5707. Hogarth, G.; Alvarez-Falcon, M. M. Inorg. Chim. Acta 2005, 358, 1386. (47) Vicente, J.; Gil-Rubio, J.; Barquero, N.; Jones, P. G.; Bautista, D. Organometallics 2008, 27, 646. (48) Siemeling, U.; Rother, D.; Bruhn, C. Chem. Commun. 2007, 4227. Chico, R.; Castillejos, E.; Serp, P.; Coco, S.; Espinet, P. Inorg. Chem. 2011, 50, 8654. (49) Vicente, J.; Chicote, M. T.; Abrisqueta, M. D.; Á lvarez-Falcón, M. M. J. Organomet. Chem. 2002, 663, 40. (50) Garrison, J. C.; Youngs, W. J. Chem. Rev. 2005, 105, 3978. (51) Wang, H. M. J.; Vasam, C. S.; Tsai, T. Y. R.; Chen, S.-H.; Chang, A. H. H.; Lin, I. J. B. Organometallics 2005, 24, 486. (52) Patil, S.; Deally, A.; Hackenberg, F.; Kaps, L.; Müller-Bunz, H.; Schobert, R.; Tacke, M. Helv. Chim. Acta 2011, 94, 1551. (53) Vicente, J.; Chicote, M. T.; Abrisqueta, M. D.; Á lvarez-Falcón, M. M.; Ramírez de Arellano, M. C.; Jones, P. G. Organometallics 2003, 22, 4327. (54) Hashmi, A. S. K.; Hengst, T.; Lothschütz, C.; Rominger, F. Adv. Synth. Catal. 2010, 352, 1315. Bartolomé, C.; García-Cuadrado, D.; Ramiro, Z.; Espinet, P. Inorg. Chem. 2010, 49, 9758. (55) Chao, H. Y.; Lu, W.; Li, Y. Q.; Chan, M. C. W.; Che, C. M.; Cheung, K. K.; Zhu, N. Y. J. Am. Chem. Soc. 2002, 124, 14696. (56) Li, D.; Hong, X.; Che, C. M.; Lo, W. C.; Peng, S. M. J. Chem. Soc., Dalton Trans. 1993, 2929. (57) Lu, W.; Zhu, N. Y.; Che, C. M. J. Am. Chem. Soc. 2003, 125, 16081. (58) Baron, M.; Tubaro, C.; Biffis, A.; Basato, M.; Graiff, C.; Poater, A.; Cavallo, L.; Armaroli, N.; Accorsi, G. Inorg. Chem. 2012, 51, 1778. (59) Xu, H.-B.; Zhang, L.-Y.; Ni, J.; Chao, H.-Y.; Chen, Z.-N. Inorg. Chem. 2008, 47, 10744. (60) Coates, G. E.; Parkin, C. J. Chem. Soc. 1962, 3220. (61) Takahashi, S.; Kuroyama, Y.; Sonogashira, K.; Hagihara, N. Synthesis 1980, 627. (62) Grosshenny, V.; Romero, F. M.; Ziessel, R. J. Org. Chem. 1997, 62, 1491. (63) Wang, J.-W.; Song, H.-B.; Li, Q.-S.; Xu, F.-B.; Zhang, Z.-Z. Inorg. Chim. Acta 2005, 358, 3653.

5426


Dinuclear Alkynyl Gold(I) Complexes Containing Bridging N

Recommend Documents