Trapping of a Doubly Unsaturated Dinuclear Iridium(II) Sulfonylimido

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Trapping of a Doubly Unsaturated Dinuclear Iridium(II) Sulfonylimido Complex with Phosphine and Lewis Acidic Group 11 and 12 Metals Takashi Kimura, Koji Ishiwata, Shigeki Kuwata,* and Takao Ikariya* Department of Applied Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology, O-okayama, Meguro-ku, Tokyo 152-8552, Japan S Supporting Information *

ABSTRACT: Isolation of the doubly unsaturated mono(sulfonylimido)-bridged diiridium(II) complex [(Cp*Ir)2(μ2-NMs)] (5; Cp* = η5-C5Me5, Ms = SO2Me), which would be generated by 2-fold dehydrochlorination of the sulfonylamido-bridged diiridium(III) complex [(Cp*IrCl)2(μ2H)(μ2-NHMs)] (2), was attempted. Treatment of 2 with 2 equiv of a base in the presence of trimethylphosphine afforded the mono(phosphine) adduct [(Cp*Ir)2(μ2-NMs)(PMe3)] (6), while dehydrochlorination of 2 with dimethylzinc and silver acetate led to the formation of the mixed-metal clusters [(ZnCl2)(Cp*Ir)2(μ2-NMs)] (7) and [(AgCl)2(μ2-Cl)2Ag2{(Cp*Ir)2(μ2-NMs)}2] (8), respectively. The detailed structures of 6−8, containing the imido-bridged diiridium(II) core of 5, have been determined by X-ray analysis.

T

Scheme 1

he coordinatively unsaturated late-transition-metal amido complexes are known to promote bond cleavage reactions of various pronucleophiles and even unpolarized dihydrogen, owing to the cooperation of the Lewis acidic metal center and the Brønsted basic nitrogen atom without formal changes of the oxidation state of the central metal.1 This bifunctional nature of the metal−amido bond led to the development of a number of mononuclear amido/amine catalysts.2 In contrast, the cooperation of the metal and nitrogen-donor ligand in dinuclear imido/amido complexes, which may be accompanied by synergetic reactivities and facile redox of the two metal centers, remains much less explored.3−9 In one manifestation of this chemistry, we have recently developed an imido-bridged dirhodium catalyst, which promotes aerobic oxidation of molecular hydrogen under mild conditions through hydrogenation of the metal−imido bond and reduction of the dirhodium core.4 We have also isolated and fully characterized a pair consisting of the coordinatively unsaturated dinuclear imido complex 1 and saturated amido−chlorido complex 2, which are linked by reversible addition of hydrogen chloride across the metal−nitrogen bond in 1 (Scheme 1).5 Notably, coordination of π-accepting carbon monoxide to the diiridium(III) complex 1 causes hydrido migration to the imido ligand to give the amido complex 3 with an Ir(II) oxidation state, which is rarely accessible in mononuclear complexes.10 One may expect that the Ir(II) amido complex 3 also undergoes reversible dehydrochlorination; actually, treatment of 3 under carbon monoxide provides the imido complex 4.5 The strongly coordinated CO ligands, however, prevent the imido-bridged dinuclear core from activating pronucleophiles (NuH) and another substrate L simultaneously, as illustrated in eq 1. As a part of our efforts to isolate the putative carbonyl-free and doubly unsaturated complex 5,11 we report here the formation of a series of compounds containing the imido-bridged © 2012 American Chemical Society

diiridium(II) core of 5 from dehydrochlorination reactions of the amido complex 2 in the presence of a phosphine or group 11 and 12 metals. These Lewis base and acids are shown to perturb the Ir2(μ2-NMs) framework significantly.

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RESULTS AND DISCUSSION When the mono(sulfonylamido)-bridged complex 2 was treated with a base and trimethylphosphine in a molar ratio of 1:2:1, the imido-bridged diiridium(II) phosphine complex 6 was obtained in moderate yield (eq 2). The 1H NMR spectrum of 6 exhibits two inequivalent Cp* resonances, only one of which is split into a doublet with 4JPH = 2.3 Hz; no signals Received: December 8, 2011 Published: February 1, 2012 1204

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Scheme 2

attributable to hydrido or amido ligands are observed. An X-ray analysis revealed that 6 is a mono(phosphine) adduct of the doubly unsaturated diiridium(II) imido complex 5, as shown in Figure 1; selected bond distances and angles are given in Table

1

H NMR spectrum of 7, only the Cp* and mesityl singlets appear in an intensity ratio of 30:3, in agreement with the symmetrical structure without the hydride and amido hydrogens. The trinuclear structure of 7 has been determined by an X-ray analysis (Figure 2). The Ir−Zn distances (2.565 Å, mean)

Figure 1. Structure of 6. Hydrogen atoms are omitted for clarity. Ir(1)−P(1) = 2.2468(12) Å.

Table 1. Selected Bond Lengths (Å) and Angles (deg) in the Ir2(μ2-NMs) Core of 6−8 Ir(1)−Ir(2) Ir(1)−N(1) Ir(2)−N(1) N(1)−S(1) S(1)−O(1) S(1)−O(2) Ir(1)−N(1)−Ir(2) Ir(1)−N(1)−S(1) Ir(2)−N(1)−S(1)

6

7

8·2CH2Cl2

2.6514(5) 2.042(4) 1.902(4) 1.587(4) 1.446(4) 1.444(4) 84.40(15) 137.9(3) 133.8(3)

2.7207(8) 1.903(7) 1.904(7) 1.653(7) 1.440(8) 1.427(8) 91.2(3) 135.1(4) 133.5(5)

2.8107(4) 1.917(6) 1.913(5) 1.640(5) 1.425(5) 1.430(6) 94.4(3) 131.9(3) 133.7(4)

Figure 2. Structure of Ir2Zn cluster 7. Hydrogen atoms are omitted for clarity. Selected bond lengths (Å): Ir(1)−Zn(1), 2.5664(15); Ir(2)− Zn(1), 2.5630(14); Zn(1)−Cl(1), 2.267(4); Zn(1)−Cl(2), 2.238(4).

are comparable with the sum of the covalent radii of iridium and zinc (2.51 Å),12 while the Ir−Ir bond is 0.07 Å longer than that in 6, suggesting delocalization of the metal−metal bonding electrons (Table 1). Thus, 7 is formally regarded as a Lewis acid−base adduct of 5 and ZnCl2 containing Ir(II)→Zn(II) dative bonds. Such a dative interaction from electron-rich transition metals to group 11−13 metals is described in the literature.13 The planarity at the imido nitrogen and the short Ir−N distances in 7 are indicative of π bonding. Notably, the N−S bond in 7 is elongated to the range of those found in μsulfonylamido complexes without N−S π bonding (1.64(1)− 1.673(6) Å),3,5 implying that the π donation from the imido nitrogen atom shifts to the diiridium(II) center to supply electrons for the Ir→Zn dative bonds. The Ir2ZnN framework is almost flat, with a Zn(1)−Ir(1)−Ir(2)−N(1) dihedral angle of 171.1(4)°. Similarly, the silver adduct was obtained by the reaction of the amido−chlorido complex 2 with silver acetate (Scheme 2). The X-ray analysis revealed that the product 8 consists of an Ir4Ag4 octanuclear core with a crystallographically imposed centrosymmetry (Figure 3). The silver, chlorine, nitrogen, and sulfur atoms almost lie in the same plane, which is perpendicular to the planes defined by the atoms around the sp2-hybridized imido nitrogen atoms. As summarized in Table 1, the Ir−N and N−S distances in 8 are comparable with those in the zinc adduct 7, while the Ir−Ir bonds are much elongated, possibly because of the electron delocalization to the two Lewis acidic silver atoms as well as the increased steric repulsion. The

1. The Ir(2)−N bond that remains unsaturated (1.902(4) Å) is significantly shorter than the saturated Ir(1)−N bond (2.042(4) Å), as in the hydrido−chlorido complex 1.5 Both of the Ir−N bonds are somewhat longer than the corresponding bonds in the closely related butylimido-bridged complex [(Cp*Ir) 2(μ2-NBut)(PMePh2)] (1.810(10) and 2.031(10) Å),7 indicating the reduced π donation of the imido ligand due to the electron-withdrawing sulfonyl group with some N−S π bonding.3 The imido nitrogen is almost planar with an angle sum around the N(1) atom of 356.1°. The Ir−Ir distance of 6 (2.6514(5) Å) is only slightly shorter than those in the butylimido complex (2.694(1) Å)7 and dicarbonyl complex 4 (2.6827(2) Å)5 and indicates the presence of an Ir(II)−Ir(II) single bond. Formation of 6 may be described as reductive elimination of hydrogen chloride from a phosphine adduct of 1, [Cp*IrCl(μ2-NMs)(μ2-H)Ir(PMe3)Cp*].5 We next examined the reactions of 2 with group 11 and 12 metal compounds as dehydrochlorinating reagents, since these Lewis acidic metals may increase the Brønsted acidity of the hydride in 2 and stabilize the electron-rich diiridium(II) centers in 5. Treatment of 2 with an equimolar amount of dimethylzinc led to the formation of the imido-bridged zinc−iridium cluster [(ZnCl2)(Cp*Ir)2(μ2-NMs)] (7), as shown in Scheme 2. In the 1205

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over the course of 2 h and then evaporated to dryness. The resultant solid was extracted with diethyl ether (12 mL), and the concentrated extract was kept at −30 °C. The green crystals that formed were filtered off and dried in vacuo (65.9 mg, 0.0800 mmol, 58%). 1H NMR (C6D6): δ 2.95 (s, 3H, SO2Me), 2.05 (s, 15H, 4JPH = 2.3 Hz, Cp*IrP), 1.62 (s, 15H, Cp*), 1.14 (d, 9H, 2JPH = 9.6 Hz, PMe3). 31P{1H} NMR (C6D6): δ −37.8 (s). Anal. Calcd for C24H42Ir2NO2PS: C, 34.98; H, 5.14; N, 1.70. Found: C, 35.04; H, 5.09; N, 1.69. Preparation of 7. To a suspension of 2 (139.7 mg, 0.170 mmol) in toluene (15 mL) was added a n-hexane solution of dimethylzinc (1.0 M, 170.2 μL, 0.170 mmol) at −78 °C. The reaction mixture was slowly warmed to room temperature with stirring. After 13 h, the resultant deep orange solution was evaporated to dryness and the resultant solid was extracted with dichloromethane (10 mL). After removal of the solvent in vacuo, recrystallization from dichloromethane−hexane (3 mL/40 mL) at 0 °C afforded 7 as brown crystals (42.3 mg, 0.0479 mmol, 28%). 1H NMR (C6D6): δ 2.54 (s, 3H, SO2Me), 1.68 (s, 30H, Cp*). Anal. Calcd for C21H33Cl2Ir2NO2SZn: C, 28.52; H, 3.76; N, 1.58. Found: C, 28.27; H, 3.89; N, 1.68. Preparation of 8·2CH2Cl2. A mixture of 2 (145.0 mg, 0.177 mmol) and silver triflate (58.7 mg, 0.352 mmol) in THF (15 mL) was stirred for 18 h at room temperature. After removal of the solvent in vacuo, the resultant solid was extracted with dichloromethane (15 mL). The extract was recrystallized from dichloromethane−diethyl ether (8 mL/60 mL) to yield 8·2CH2Cl2 as brown crystals (158.4 mg, 0.0707 mmol, 80%). 1H NMR (CD2Cl2): δ 2.92 (s, 6H, SO2Me), 2.19 (s, 60H, Cp*). Anal. Calcd for C44H70Ag4Cl8Ir4N2O4S2: C, 23.60; H, 3.15; N, 1.25. Found: C, 23.70; H, 3.14; N, 1.26. Crystallography. Single crystals suitable for X-ray analyses were mounted on glass fibers. Diffraction experiments were performed on a Rigaku Saturn CCD area detector with graphite-monochromated Mo Kα radiation (λ = 0.710 70 Å). Intensity data were corrected for Lorentz−polarization effects and for absorption. Details of data collection and refinement parameters are summarized in ref 16. Structure solution and refinements were carried out by using the CrystalStructure program package.17 The heavy-atom positions were determined by a Patterson method program (PATTY;18 for 6 and 8·2CH2Cl2) or a direct methods program (SIR92;19 for 7), and the remaining non-hydrogen atoms were found by subsequent Fourier syntheses. All non-hydrogen atoms were refined anisopropically by full-matrix least-squares techniques based on F2. The hydrogen atoms were placed at calculated positions and included in the refinements with a riding model.

Figure 3. Structure of the Ir4Ag4 cluster 8·2CH2Cl2. Hydrogen atoms as well as the solvating molecules are omitted for clarity. Asterisks denote atoms generated by a symmetry operation (1 − x, 1 − y, 1 − z). Selected interatomic distances (Å): Ir(1)−Ag(1), 2.7976(6); Ir(1)−Ag(2), 2.7646(6); Ir(2)−Ag(1), 2.7986(6); Ir(2)−Ag(2), 2.7519(7); Ag(1)−Ag(1)*, 3.7458(6); Ag(1)−Ag(2), 2.8607(8); Ag(1)−Cl(1), 2.5166(17); Ag(1)−Cl(1)*, 2.6961(16); Ag(2)− Cl(2), 2.390(3).

Ir−Ag distances (2.7519(7)−2.7986(6) Å) are in line with the presence of Ir(II)→Ag(I) dative interactions, considering the covalent radii of iridium and silver (1.26 and 1.34 Å).12 The close Ag(1)−Ag(2) contact of 2.8607(8) Å may be ascribed to the argentophilic interaction14 or the geometrical constraint imposed by the Ir2(μ2-NMs) core. The long Ag(1)−Ag(1)* distance (3.7458(6) Å) precludes any direct bonding interaction. The Ag−Ir and Ag−Cl bonds around the Ag(2) atom are shorter than those around the Ag(1) atom, suggesting the more Lewis acidic nature of the Ag(2) atom with a lower coordination number. The Ir4Ag4 octanuclear core in 8 is preserved in solution on the basis of 1H NMR and ESI-MS spectroscopy. In summary, we have demonstrated that the dinuclear Lewis acid−base bifunctional complex 5 could be stabilized by both a Lewis base (PMe3) and acids (ZnCl2 and AgCl). The adduct formation exclusively occurs at the coordinatively unsaturated yet electron-rich Ir(II) centers despite of the presence of the potentially Brønsted basic imido ligand and unsaturated M−N bonds.8,15 These Lewis acid−base adducts 6−8 could be regarded as precursors for the doubly unsaturated diiridium(II) imido complex 5. In fact, preliminary experiments revealed that the silver adduct 8 reacts with CO (1 atm) at room temperature to afford the dicarbonyl complex 4 quantitatively. The present work also highlights the electronically flexible nature of the sulfonyl group, which modulates the electron donation to the imido ligand without changing the configuration of the imido nitrogen.

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ASSOCIATED CONTENT

S Supporting Information *

CIF files giving X-ray crystallographic data for 6, 7, and 8·2CH2Cl2. This material is available free of charge via the Internet at http://pubs.acs.org.

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AUTHOR INFORMATION

Corresponding Author

*E-mail: [email protected] (S.K.); [email protected]. ac.jp (T.I.). Notes

EXPERIMENTAL SECTION

The authors declare no competing financial interest.

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General Considerations. All manipulations were performed under an atmosphere of argon using standard Schlenk techniques unless otherwise specified. Solvents were dried by refluxing over sodium benzophenone ketyl (THF, toluene, diethyl ether, and hexane) and CaH2 (dichloromethane), and distilled before use. Complex 2 was prepared according to the literature.5 1H (399.78 MHz) and 31P (161.83 MHz) NMR spectra were obtained on a JEOL JNM-ECX-400 spectrometer. Elemental analyses were performed on a Perkin-Elmer 2400II CHN analyzer. Preparation of 6. To a solution of 2 (114.1 mg, 0.139 mmol) in THF (10 mL) was added trimethylphosphine (14.4 μL, 0.139 mmol) and a suspension of K[N(SiMe3)2] (55.6 mg, 0.279 mmol) in THF (5 mL) at −78 °C. The mixture was slowly warmed to room temperature

ACKNOWLEDGMENTS This work was supported by a Grant-in-Aid for Scientific Research (S) (22225004) from the Ministry of Education, Culture, Sports, Science and Technology of Japan and the Iwatani Naoji Foundation (S.K.).

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REFERENCES

(1) (a) Fryzuk, M. D.; Montgomery, C. D. Coord. Chem. Rev. 1989, 95, 1. (b) Takebayashi, S.; Dabral, N.; Miskolzie, M.; Bergens, S. H. J. Am. Chem. Soc. 2011, 133, 9666. (c) Zhu, Y.; Chen, C.-H.; Fafard, C.

1206

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M.; Foxman, B. M.; Ozerov, O. V. Inorg. Chem. 2011, 50, 7980. (d) Webb, J. R.; Munro-Leighton, C.; Pierpont, A. W.; Gurkin, J. T.; Gunnoe, T. B.; Cundari, T. R.; Sabat, M.; Petersen, J. L.; Boyle, P. D. Inorg. Chem. 2011, 50, 4195. (e) Askevold, B.; Nieto, J. T.; Tussupbayev, S.; Diefenbach, M.; Herdtweck, E.; Holthausen, M. C.; Schneider, S. Nat. Chem. 2011, 3, 532. (f) Fullmer, B. C.; Fan, H.; Pink, M.; Huffman, J. C.; Tsvetkov, N. P.; Caulton, K. G. J. Am. Chem. Soc. 2011, 133, 2571. (2) (a) Ikariya, T. Bull. Chem. Soc. Jpn. 2011, 84, 1. (b) Touge, T.; Hakamata, T.; Nara, H.; Kobayashi, T.; Sayo, N.; Saito, T.; Kayaki, Y.; Ikariya, T. J. Am. Chem. Soc. 2011, 133, 14960. (c) Ito, M.; Ootsuka, T.; Watari, R.; Shiibashi, A.; Himizu, A.; Ikariya, T. J. Am. Chem. Soc. 2011, 133, 4240. (d) John, J. M.; Bergens, S. H. Angew. Chem., Int. Ed. 2011, 50, 10377. (e) Trincado, M.; Kühlein, K.; Grützmacher, H. Chem. Eur. J. 2011, 17, 11905. (f) Bertoli, M.; Choualeb, Gusev, D. G.; Lough, A. J.; Major, Q.; Moore, B. Dalton Trans. 2011, 40, 8941. (g) Ren, P.; Vechorkin, O.; Csok, Z.; Salihu, I.; Scopelliti, Hu, X. Dalton Trans. 2011, 40, 8906. (h) Bertoli, M.; Choualeb, A.; Lough, A. J.; Moore, B.; Spasyuk, D.; Gusev, D. G. Organometallics 2011, 30, 3479. (i) Andrushko, N.; Andrushko, V.; Roose, P.; Moonen, K.; Bçrner, A. ChemCatChem 2010, 2, 640. (j) Grützmacher, H. Angew. Chem., Int. Ed. 2008, 47, 1814. (k) Maire, P.; Büttner, T.; Breher, F.; Le Floch, P.; Grützmacher, H. Angew. Chem., Int. Ed. 2005, 44, 6318. (l) Clapham, S. E.; Hadzovic, A.; Morris, R. H. Coord. Chem. Rev. 2004, 248, 2201. (3) Kuwata, S.; Ikariya, T. Dalton Trans. 2010, 39, 2984. (4) Ishiwata, K.; Kuwata, S.; Ikariya, T. J. Am. Chem. Soc. 2009, 131, 5001. (5) Arita, H.; Ishiwata, K.; Kuwata, S.; Ikariya, T. Organometallics 2008, 27, 493. (6) Takemoto, S.; Otsuki, S.; Hashimoto, Y.; Kamikawa, K.; Matsuzaka, H. J. Am. Chem. Soc. 2008, 130, 8904. (7) Dobbs, D. A.; Bergman, R. G. Organometallics 1994, 13, 4594. (8) (a) Oro, L. A.; Ciriano, M. A.; Tejel, C.; Bordonaba, M.; Graiff, C.; Tiripicchio, A. Chem. Eur. J. 2004, 10, 708. (b) Takemoto, S.; Morita, H.; Kamikawa, K.; Matsuzaka, H. Chem. Commun. 2006, 1328. (9) (a) Takemoto, S.; Kobayashi, T.; Matsuzaka, H. J. Am. Chem. Soc. 2004, 126, 10802. (b) Ohki, Y.; Takikawa, Y.; Hatanaka, T.; Tatsumi, K. Organometallics 2006, 25, 3111. (c) Ishiwata, K.; Kuwata, S.; Ikariya, T. Organometallics 2006, 25, 5847. (d) Ishiwata, K.; Kuwata, S.; Ikariya, T. Dalton Trans. 2007, 3606. (e) Hoover, J. M.; DiPasquale, A.; Mayer, J. M.; Michael, F. E. Organometallics 2007, 26, 3297. (f) Tejel, C.; Ciriano, M. A.; López, J. A.; Jiménez, S.; Bordonaba, M.; Oro, L. A. Chem. Eur. J. 2007, 13, 2044. (g) Takemoto, S.; Kimura, Y.; Kamikawa, K.; Matsuzaka, H. Organometallics 2008, 27, 1780. (h) Tejel, C.; Ciriano, M. A.; Jiménez, S.; Passarelli, V.; López, J. A. Inorg. Chem. 2008, 47, 10220. (i) Tejel, C.; Ciriano, M. A.; Passarelli, V.; López, J. A.; de Bruin, B. Chem. Eur. J. 2008, 14, 10985. (j) Takemoto, S.; Kobayashi, T.; Ito, T.; Inui, A.; Karitani, K.; Katagiri, S.; Masuhara, Y.; Matsuzaka, H. Organometallics 2011, 30, 2160. (k) Kimura, T.; Koiso, N.; Ishiwata, K.; Kuwata, S.; Ikariya, T. J. Am. Chem. Soc. 2011, 133, 8880. (10) Meiners, J.; Scheibel, M. G.; Lemée-Cailleau, M.-H.; Mason, S. A.; Boeddinghaus, M. B.; Fässler, T. F.; Herdtweck, E.; Khusniyarov, M. M.; Schneider, S. Angew. Chem., Int. Ed. 2011, 50, 8184. (11) Recently, Takemoto, Matsuzaka, and co-workers determined the crystal structure of the rhodium analogue of the doubly unsaturated species [(Cp*Rh)2(μ2-NC6H3Pri2-2,6)], which is derived from an Rh(II) chloride and bulky amide anion.6 (12) Dean, J. A., Ed. Lange’s Handbook of Chemistry, 13th ed.; McGraw-Hill: New York, 1985. (13) Selected examples: (a) Clark, G. R.; Cochrane, C. M.; Marsden, K.; Roper, W. R.; Wright, L, J. J. Organomet. Chem. 1986, 315, 211. (b) Stockhammer, A.; Dahmen, K.-H.; Gerfin, T.; Venanzi, L. M.; Gramlich, V.; Petter, W. Helv. Chim. Acta 1991, 74, 989. (c) Einstein, F. W. B.; Yan, X.; Zhang, X.; Sutton, D. J. Organomet. Chem. 1992, 439, 221. (d) Chan, W.-H.; Zhang, Z.-Z.; Mak, T. C. W.; Che, C.-M. J. Chem. Soc., Dalton Trans. 1998, 803. (e) Oro, L. A.; Ciriano, M. A.; Tejel, C.; Shi, Y.-M.; Modrego, J. In Metal Clusters in Chemistry;

Braunstein, P., Oro, L. A., Raithby, P. R., Eds.; Wiley-VCH: Weinheim, Germany, 1999; pp 381−398. (f) Alonso, E.; Forniés, J.; Fortuño, C.; Lledós, A.; Martín, A.; Nova, A. Inorg. Chem. 2009, 48, 7679. (g) Alvarez, M. A.; García, M. E.; García-Vivó, D.; Marínez, M. E.; Ruiz, M. A. Inorg. Chem. 2009, 48, 9767. (h) Sculfort, S.; Welter, R.; Braunstein, P. Inorg. Chem. 2010, 49, 2372. (i) Jamali, S.; Mazloomi, Z.; Nabavizadeh, S. M.; Milić, D.; Kia, R.; Rashidi, M. Inorg. Chem. 2010, 49, 2721. (j) Forniés, J.; Fortuño, C.; Ibáñez, S.; Martín, A.; Mastrorilli, P.; Gallo, V. Inorg. Chem. 2011, 50, 10798. (k) Bauer, J.; Braunschweig, H.; Damme, A.; Gruß, K.; Radacki, K. Chem. Commun. 2011, 47, 12783. (l) Alex Rudd, P.; Liu, S.; Gagliardi, L.; Young, V. G. Jr.; Lu, C. C. J. Am. Chem. Soc. 2011, 133, 20724. (14) (a) Pyykkö, P. Chem. Rev. 1997, 97, 597. (b) Zhang, T.; Ji, C.; Wang, K.; Fortin, D.; Harvey, P. D. Inorg. Chem. 2010, 49, 11069. (c) Li, B.; Zang, S.-Q.; Liang, R.; Wu, Y.-J.; Mak, T. C. W. Organometallics 2011, 30, 1710. (d) Desmarets, C.; Azcarate, I.; Gontard, G.; Amouri, H. Eur. J. Inorg. Chem. 2011, 4558. (e) Guo, L.R.; Tong, J.-W.; Liang, X.; Köller, J.; Nuss, J.; Li, Y.-Z.; Zheng, L.-M. Dalton Trans. 2011, 40, 6392. (f) Yang, C.; Elbjeirami, O.; Palehepiya Gamage, C. S.; Dias, H. V. R.; Omary, M. A. Chem. Commun. 2011, 47, 7434. (g) Jin, J.; Wang, W.; Liu, Y.; Hou, H.; Fan, Y. Chem. Commun. 2011, 47, 7461. (15) For addition of metal fragments to unsaturated late metal− amido and imido bonds, see: (a) Glueck, D. S.; Wu, J.; Hollander, F. J.; Bergman, R. G. J. Am. Chem. Soc. 1991, 113, 2041. (b) Baranger, A. M.; Bergman, R. G. J. Am. Chem. Soc. 1994, 116, 3822. (c) Fryzuk, M. D.; Huang, L.; McManus, N. T.; Paglia, P.; Rettig, S. J.; White, G. S. Organometallics 1992, 11, 2979. (d) Smith, D. A.; Ozerov, O. V. Chem. Commun. 2011, 47, 10779. (16) Crystal data for 6: C24H42Ir2NO2PS, fw = 824.08, T = 193 K, monoclinic, P21/n, a = 11.008(2) Å, b = 15.888(3) Å, c = 15.922(4) Å, β = 99.287(3)°, V = 2748.1(10) Å3, Z = 4, ρcalcd = 1.992 g cm−3, 6097 unique reflections (2θ < 55°), 322 parameters, R1 = 0.025 (I > 2σ(I)), wR2 = 0.070 (all data), GOF = 1.000. Crystal data for 7: C21H33Cl2Ir2NO2SZn, fw = 884.28, T = 193 K, monoclinic, P21/c, a = 14.259(5) Å, b = 11.096(4) Å, c = 17.234(6) Å, β = 93.460(6)°, V = 2721.8(16) Å3, Z = 4, ρcalcd = 2.158 g cm−3, 6197 unique reflections (2θ < 55°), 304 parameters, R1 = 0.045 (I > 2σ(I)), wR2 = 0.089 (all data), GOF = 1.003. Crystal data for 8·2CH2Cl2: C44H70Ag4Cl8Ir4N2O4S2, fw = 2239.14, T = 193 K, monoclinic, P21/ c, a = 14.616(2) Å, b = 10.8891(8) Å, c = 19.568(3) Å, β = 107.876(5) °, V = 2963.8(6) Å3, Z = 2, ρcalcd = 2.509 g cm−3, 6508 unique reflections (2θ < 55°), 342 parameters, R1 = 0.027 (I > 2σ(I)), wR2 = 0.068 (all data), GOF = 1.089. (17) CrystalStructure 3.8: Crystal Structure Analysis Package; Rigaku and Rigaku/MSC, The Woodlands, TX, 2000−2006. (18) Beurskens, P. T.; Admiraal, G.; Behm, H.; Beurskens, G.; Bosman, W. P.; García-Granda, S.; Gould, R. O.; Smits, J. M. M.; Smykalla, C. Z. Kristallogr 1991, No. Suppl. 4, 99. (19) Altomare, A.; Cascarano, G.; Giacovazzo, C.; Guagliardi, A.; Burla, M.; Polidori, G.; Camalli, M. J. Appl. Crystallogr. 1994, 27, 435.

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