Organometallics 1996, 14, 1310-1315
1310
Heterobridged Dinuclear Gold(1) and Gold(I1) Complexes with Xanthate Ligands. X-ray Structures of [Au2{p-(CH2)2PPh2} @-S2COiPr)land [Au2{p-(CHz)aPPbI@-SzCOMe)Br21 Manuel Bardaji,? Peter G. Jones,* Antonio Laguna,**+and Mariano Laguna? Departamento de Quimica Inorgcinica, Instituto de Ciencia de Materiales de Aragbn, Universidad de Zaragoza-CSIC, E-50009Zaragoza, Spain, and Institut fur Anorganische und Analytische Chemie, Technische Universitat Braunschweig, Postfach 3329,D-38023 Braunschweig, Germany Received September 20, 1994@ The reaction of [Au,(S&OR),I (R = Me, Et, 'Pr) with [Au~@-L-L)~P+ (z = 0, L-L = CH2PPh2CH2; z = 2, L-L= PPh2CH2PPh2, PPh2CH2CH2PPh2) leads through a bidentate ligand transfer to heterobridged dinuclear complexes [Au~(L&~COR)@-L-L)P+ (z = 0 , l ) . The crystal shows a short intramolecular gold-gold distance structure of [Au2{p-(CH2)2PPh~}@-S2COiPr)] of 2.8809(9) A. It crystallizes in the monoclinic space group P21/c with a = 8.571(3) A, b = 10.219(4) c = 23.210(6) A, 8, = 97.37(3)", and 2 = 4 (at -100 "C). The oxidative addition of halogen affords the corresponding neutral gold(11)complexes containing xanthate ligands [AU~{~-(CH~)~PP~~}C~-S~COR)X~] (R = Me, Et, 'Pr; X = C1, Br, I). [Auz{p-(CH2hPPh2}@S2COMe)Br2]crystallizes in the triclinic space group Pi with a = 12.917(4) b = 13.864(3) c = 15.975(5) a = 106.05(2)", p = 96.27(2)", y = 113.78(2)", and 2 = 4 (at -100 "C). The molecule possesses the general features of dinuclear gold(I1) complexes, including a short gold-gold bond of 2.566(1)
A,
A,
A,
A,
A.
Introduction Dithiocarbamate gold(I),' gold(III),1a?2 and even gold(HI3complexes have been extensively studied. Gold(1) derivatives have attracted much interest because of the presence of very short intra- and intermolecular goldgold distances. In contrast, although the first gold(1) xanthate complexes [Au,( S2COR),] were obtained in 1945,4 only a few gold(1) or gold(II1) compounds of stoichiometry [Au(S2COR)(PR3),1(n = 1,2)5or [AuMes(Szhave been described, and no gold(I1) xanthate complexes have been reported. In this paper we describe the syntheses not only of several new gold(1) complexes (via bidentate ligand transfer) but also of gold(I1) complexes containing xanthate ligands. All the products are heterobridged dinuclear complexes with a xanthate and a (bis)ylide or diphosphine ligand bridging the two gold centers. The molecular structures of [Au2@-(CHz)zPPh2}@-SzCOiPr)l Wniversidad de Zaragoza-CSIC. Technische Universitat Braunschweig. Abstract published in Advance ACS Abstracts, January 15, 1995. ( l ) ( a ) Coucouvanis, D. Prog. Inorg. Chem. 1979, 26, 301 and references therein. (b) Nazrul, M.; Khan, I.; King, C.; Heinrich, D. D.; Fackler, J. P., Jr.; Porter, L. C.; Inorg. Chem. 1989,28,2150. (c) Heinrich, D.D.; Wang, J.; Fackler, J. P., Jr. Acta Crystallogr., Sect. C 1990,46, 1444 and references therein. (2)(a) Beckett, M. A.; Crook, J. E.; Greewood, N. N.; Kennedy, J. D. J . Chem. SOC.,Dalton Trans. 1984,1427.(b) Usbn, R.; Laguna, A.; Laguna, M.; Castilla, M. L. J. Organomet. Chem. 1987,336,453.(c) Murray, H.H.; Garzbn, G.; Raptis, R. G.; Mazany, A. M.; Porter, L. C.; Fackler, J. P., Jr. Inorg. Chem. 1988,27, 836. (d) Criado, J. L.; Lbpez, J. A.; Macias, B.; Femhdez-Lago, L. R.; Sala, J. M. Inorg. Chim. Acta 1992,193,229. (3) Calabro, C.; Harrison, B. A,; Palmer, G. T.; Moguel, M. K.; Rebbert, L.; Burmeister, J. L. Inorg. Chem. 1981,20,4311. (4)Denko, C. W.; Anderson, A. K. J . Am. Chem. SOC.1946,67,2241. ( 5 ) (a) Siasios, G.; Tiekink, E. R. T. 2. Kristallogr. 1993,203, 117 and references therein. (b) Assefa, 2.; Staples, R. J.; Fackler, J. P., Jr. Inorg. Chem. 1994,33,2790. (6) Paparizos, C.; Fackler, J. P., Jr. Inorg. Chem. 1980,19,2886.
*
@
and [Au2{pCL-(CH~)2PPh2}@-S2COMe)Br21 have been established by single-crystal X-ray analysis and are the first crystal structures of dinuclear gold xanthate derivatives.
Results and Discussion We have recently d e s ~ r i b e dylide ~ * ~transfer reactions of the bidylide) derivative [Au2(p-(CH2)2PPh2}21 that allowed us t o synthesize di- and trinuclear gold(1) complexes. Now we have synthesized a series of neutral heterobridged gold(1)complexes using a bidentate ligand transfer reaction. Thus, the reaction in dichloromethane of the homobridged complex [Au2{pu-(CH2)zPPh2}2I with the insoluble complex [Au,(S2COR),I (R = Me, Et, 'Pr) leads to green solutions from which heterobridged complexes 1-3 can be isolated (eq 1).
Ai
AU
I
I
+ (2/n)[Au,(S&OR),]
-
HAp/CH2 Phz
I
2
Au
I
S
Au
I
(1)
sYs OR R = Me (I), Et (2), 'Pr (3)
These complexes were obtained as green (1, 3) or yellow (2) solids, air- and moisture-stable at room temperature. Their acetone solutions are nonconducting, and their IR spectra show medium-intensity bands ~ , ) .31P~ at ca. 570 cm-l (Table 1) due to ~ ( A U - C , . ~ ~The {lH} NMR spectra show a singlet at ca. 6 35 ppm for (7) Cerrada, E.; Gimeno, M. C.; Jimenez, J.; Laguna, A,; Laguna, M.; Jones, P. G. Organometallics 1994,13, 1470. (8) Bardaji, M.; Connelly, N. G.; Gimeno, M. C.; Jimenez, J.; Jones, P. G.; Laguna, A,; Laguna, M. J . Chem. SOC.,Dalton Trans. 1994,1163.
0276-7333/95/2314-1310$09.00/00 1995 American Chemical Society
Au(I) and Au(II) Complexes with Xanthate Ligands
Organometallics, Vol. 14,No. 3, 1995 1311
Table 1. Analytical and Spectroscopic Data for Complexes 1-17 31P{'H} NMRb
anal. (%)a complex
[A~z@-(CHZ)ZPP~Z}@-SZCOM~)I (1) [Auz@-(CHZ)~PP~Z}@-SZCOE~)I (2)
C
27.1 (26.9) 28.05 (28.05) [Auz@-(CHZ)ZPP~Z}@-SZCO~~)I (3) 29.5 (29.1) [ A U Z O ~ - S Z C O M ~ ) @ - ( P P ~ ~(4) ) ~ C H ~ ) ~33.0 C ~ ~(32.9) ~ [AU~@-SZCOE~)@-(PP~~)~CH~)]C~O~ (5) 34.0 (33.65) [AU~@-S~COM~)(~-(PP~~)ZCHZCH~)]C~O~ (6) 33.5 (33.65) [ A u z @ - S ~ C O E ~ ) @ - ( P P ~ ~ ) ~(7) C H ~ )34.5 ~ C (34.4) ~~~ [AUZ@-SZCO'P~)@-(PP~~)ZCHZCH~)]C~O~ (8) 34.9 (35.1) [A~z@-(CHZ)ZPP~Z}~~-SZCOM~)C~ZI (9) 24.3 (24.45) [ A u & - ( C H ~ ) ~ P P ~ ~ } @ S Z C O M(10) ~ ) B ~ ~ ] 21.9 (22.0) [A~z@-(CHZ)ZPP~Z}~~-SZCOM~)I~I (11) 19.65 (19.85) [Au~@-(CH~)~PP~~}@-S~COE~)C~~] (12) 25.05 (25.55) [Auz@-(CH2)2PPhz}@-SzC0Et)Br~](13) 22.85 (23.0) [AU~~~-(CHZ)ZPP~~}~~-SZCOE~)IZI (14) 20.8 (20.8) [Au~@-(CH~)~PP~~}@-S~COIPT)C~~] (15) 27.0 (26.6) [AU~@-(CH~)~PP~~}~-SZCO~P~)B~ZI (16) 23.95 (23.95) ~ ~ ~ z @ - ~ ~ ~ z ~ z ~ (17) ~ ~ z ~ O 21.65 1 - ~(21.7) z ~ ~
H
dyhde
2.35 (2.4) 2.55 (2.65) 2.85 (2.85) 2.65 (2.55) 2.9 (2.7) 2.55 (2.7) 2.95 (2.9) 2.9 (3.05) 2.05 (2.2) 2.15 (1.95) 1.95 (1.75) 2.35 (2.4) 2.0 (2.15) 1.65 (1.95) 2.8 (2.6) 2.45 (2.35) l 2.35 ~ ~(2.1) ~ z l
'H NMR' d(CH2-Au)
dphos
34.7 (s) 34.8 (s) 34.5 (s)
IRd Y(AU-C~II&)
1.96 (d) (12.7) 1.95 (d) (12.7) 1.93 (d) (12.6)
568 572 572
2.83 (d) (8.8) 2.91 (d) (8.8) 2.97 (d) (9.0) 2.78 (d) (8.8) 2.85 (d) (8.8) 2.93 (d) (9.1) 2.81 (d) (8.8) 2.89 (d) (8.8) 2.91 (d) (9.1)
574 572 570 576 574 570 572 567 570
37.5 (s) 37.3 (s) 33.7 (s) 33.7 (s) 33.7 (s) 42.2 (s) 45.6 (s) 52.9 (s) 42.4 (s) 45.7 (s) 52.9 (s) 42.2 (s) 45.6 (s) 52.7 (s)
Calculated values are given in parentheses. Recorded in CDCl3, referenced to extemal H3P04; values in ppm. In CDC13 at 300 MHz, referenced to extemal SiMe4; values in ppm. Coupling constants in Hz are given in parentheses: s = singlet, d = doublet. Values in cm-'. (I
Table 2. Atomic Coordinates ( x 104) and Equivalent IsotroDic Dimlacement Parameters (A2 x 1oJ) for P ~~
~
~~
X
Figure 1. Molecular structure of complex 3, with the atom-numbering scheme. Radii are arbitrary. the phosphorus atom (Table 11,displaced slightly to low field from the bis(y1ide)starting material (634.2 ppm).1° The 'H NMR spectra show the ylide methylene proton resonances as doublets at ca. 6 1.95 ppm (Table 11, again low-field displaced (6 1.30 ppm),1° showing a stronger influence of the trans ligand than do the phosphorus resonances. The positive-ion fast atom bombardment (FAB) mass spectra show in all cases the molecular cation peak (M) a t m l z (%, complex) 716 (48, l),729 (65, 2) and 743 (15, 3). The cyclic voltammograms of complexes 1 and 2 in CH2C12 show reversible oxidation waves at 0.47 and 0.48 V, respectively (scan rates 50-200 mV s-l), although they are complicated by the presence of a second irreversible oxidation a t 0.62 (1)and 0.59 V (2). These potential values are close to those found by us8 in similar dithiocarbamate complexes and show that our complexes are more difficult to oxidize than the starting material [ A U ~ @ - C H ~ P P ~ ~(0.11 C HV ~ )us~Ag-AgC1).ll I The structure of complex 3 has been confirmed by X-ray diffraction analysis (Figure 1). The structure consists of a dinuclear gold compound with a central eight-membered ring and a short transannular goldgold contact of 2.8809(9) A, similar to that found in [AU~@-(CH~)~PP~~)@-S~CNE~~)] (2.868(1)and 2.867(1) A)8 or in metallic gold (2.884 &Ic and shorter than in (9) (a)Schmidbaur, H.; Franke, R. Inorg. Chim. Acta. 1976,13,85. (b) Schmidbaur, H.; Franke, R. Chem. Ber. 1976,108,1321. (10)U s h , R.;Laguna, A,; Laguna, M.; T a r t h , M. T.; Jones, P. G. J. Chem. SOC.,Chem. Commun. 1988,740. (11)Basil, J.; Murray, H. H.; Fackler, J . P., Jr.; Tocher, J.; Mazany, A. M.; Trzcinska-Bancroft, B.;Knachel, H.; Dudis, D.; Delord, T. J.; Marler, D. 0. J.A m . Chem. SOC.1986,107,6908.
2453.0 (4) 4846.2 (4) 2973 (3) 5708 (3) 2242 (3) 5022 (8) 1935 (11) 4221 (10) 4626 (12) 6373 (12) 5824 (16) 6859 (13) 1691 (10) 967 (12) 539 (13) 800(12) 1548 (13) 1997 (13) 929 (10) -670 (10) -1691 (10) -1 120 (1 1) 434(11) 1471 (10)
~~
Y 6030.7 (4) 7522.2 (4) 6996 (3) 8433 (4) 6150 (3) 8296 (8) 5063 (10) 6695 (12) 7943 (10) 9166 (11) 10546 (12) 8831 (13) 5342 (10) 4147 (1 1) 3552 (12) 4154(11) 5332 (12) 5943 (11) 7529 (9) 7320 (10) 8354 (11) 9609 (1 1) 9856 (10) 8831 (10)
Z
5508.3 (1) 5037.5 (2) 6405.8 (11) 5932.6 (1 1) 4157.1 (10) 7000 (3) 4722 (4) 4223 (4) 6444 (4) 7192 ( 5 ) 7099 ( 5 ) 7816 (4) 3456 (4) 3429 (4) 2890 (4) 2389 (4) 2415 (4) 2949 (4) 4172 (4) 4192 (4) 4212 (4) 4220 (4) 4203 (4) 4176 (4)
U(eq) is defined as one-third of the trace of the orthogonalized Uij.
Table 3. Selected Bond Lengths Au( 1)-C( 1) Au(l)-Au(2) Au(2)-S(2) s(2)-c(3) P-C(2) P-C( 11) O-C(4) C(1)-Au( 1)-S(1) S( l)-Au( 1)-Au(2) C(2)-Au(2)-Au( 1) C(3)-S(l)-Au(l) C( l)-P-C(2) C(2)-P-C(21) C(2)-P-C( 11) C(3)-0-C(4) P-C(2)-Au(2) O-C(3)-S(l) O-C(4)-C(5)
2.073 (10) 2.8809 (9) 2.309 (3) 1.674 (10) 1.773 (9) 1.831 (10) 1.483 (12) 176.6 (3) 92.98 (7) 91.0 (3) 110.7 (3) 111.4 (5) 110.2 ( 5 ) 110.7 (4) 122.8 (8) 109.8 (4) 107.9 (7) 107.6 (9)
(A) and Angles (deg) for 3 Au(1)-S( 1) Au(2)-C(2) S(l)-C(3) P-C(1) P-C(21) O-C(3)
C( l)-Au( 1)-Au(2) C(2)-Au(2) -S(2) S(~)-AU(~)-AU( 1) C(3)-S(2)-Au(2) C( 1)-P-C(21) C(l)-P-C(ll) C(21)-P-C(11) P-C( 1)-Au(1) O-C(3)-S(2) S(2)-C(3)-S( 1) O-C(4)-C(6)
2.296 (3) 2.077 (9) 1.708 (10) 1.764 (9) 1.806 (10) 1.341 (12) 90.1 (2) 176.3 (3) 91.91 (7) 112.0 (4) 108.9 (4) 109.3 ( 5 ) 106.2 (4) 108.6 ( 5 ) 120.5 (8) 131.6 (6) 105.3 (9)
the bis(ylide)digold(I) complex [Auz@-(CH2)2Pph2>21 (2.977(1)A)l1 or in [Au,{~-(CH2)2S(O)NMe2)@-(PPh2)2-
Bardaji et al.
1312 Organometallics, Vol. 14,No.3, 1995 CH2)lBF4 (2.984(1)A).12 The main difference from these two heterobridged dinuclear gold(1) complexes is the absence of intermolecular gold-gold contacts; although the molecules pack in loose pairs antiparallel to each other, the shortest such gold-gold distance is 4.571 A. The conformation of the eight-membered ring is an “envelope”form, with the ylide P atom lying 0.75 8,out of the plane of the other seven atoms. The coordination around the gold atoms is almost linear, with C-Au-S angles of 176.3(3) and 176.6(3)”. The Au-C bond lengths, 2.073(10) and 2.077(9) A, are similar to those found in [Au2@-(CH2)2PPh2}21(2.091(7)and 2.085(7)A), and the Au-S bond distances, 2.296(3) and 2.309(3) A, are close to those found in the gold(1) xanthate complexes [Au(S~COR)(PR~)I.~ The bidentate ligand transfer processes shown in eq 1can involve donor-acceptor intermediates, as described for ylide transfer reactions. Thus, we can carry out reactions involving the homoleptic gold(1) xanthate [Aun(S&OR)n] (R = Me, Et, ’Pr) with cationic gold(1) (Y = diphosphine complexes [Au2{~-(PPh2)2Y)21(C104)2 CH2, CH2CH2) (the former acting as donor and the latter as acceptor),from which we have succeeded in obtaining heterobridged dinuclear gold(1)complexes (eq 2). These reactions proceed even faster than reaction 1.
Figure 2. The two molecules of complex 10 in the crystal, with the atom-numbering scheme. Radii are arbitrary. ion [M - C1041+ is the base peak of the spectrum at mlz 885, 899, 899, 913, and 927, respectively. The neutral dinuclear complexes 1-3 are potential precursors to gold(I1) compounds by oxidative addition of halogen, and such reactions are indeed observed, according to eq 3. To the best of our knowledge, they represent the first examples of gold(I1) complexes containing xanthate as ligand.
OR
OR R = Me, X = C1(9), Br(lO), I(11) R = Et, X = C1(12), Br(13), I(14) R =‘Pr, X = C1(15), Br(16), I(17)
L
Y = CH2, R = M0(4), Et(5) Y = CH2CH2, R = Me@), Et(7), iPr(8)
Complexes 9-17 are orange (9,10,13, 161,garnet (11,14,17), or yellow (12,15)solids, air- and moisture-
stable at room temperature, and are nonconducting in acetone solution. The IR spectra show medium-intensity bands at ca. 570 cm-l (Table 1)assignable to ~ ( A u Complexes 4-8 are air- and moisture-stable yellow Cyfide)and at 263 (9),260 (12),or 266 (15)cm-’ due to solids. They behave as 1:l electrolytes in acetone v(Au11-C1).16 The 31P{1H) NMR spectra show a singlet solutions, and their IR spectra show bands at 1100 (s, 17) at ca. 6 42 (9,12,15),46 (10,13,161,or 53 (11,14, br) and 623 (m) cm-I which are characteristic of the ppm for the phosphorus atom of the ylide group (Table C104- mi0n.l3 The 31P{1H) NMR spectra show a singlet 1). These resonances are markedly low-field-shifted at ca. 6 37 ppm (4,5) or 34 ppm (6-8) for the compared with 1-3 and follow the trend 61 > 6 B r > del, phosphorus atoms (Table 11, which imply a dinuclear as already observed in [AU~@-(CH~)~PP~~)C~-S~CNR~)structure as in complexes 1-3, rather than a tetraX2]l7 and the symmetrical complexes [Au2@-(CH2)2nuclear structure, in which we should expect compliPPh2}&21.11 In the lH NMR spectra the ylide methylcated spectra as found in [AuqCU-dmit)z{~-(PPh2)2- ene proton resonances appear as doublets, which fall CHZ}&~ (dmit = 4,5-dimercapto-l,3-dithiole-2-thionate) in the range 6 2.78-2.97 ppm (Table 1);again they are or in [Au4(MNT)(dppee)2Cl21l5(MNT = 1,2-dicyanolow-field-shifted and display the same order 61 > bBr > ethene-1,2-dithiolate; dppee = cis-bis(dipheny1phosphi6 ~ 1 . lThe ~ FAEV mass spectra do not show the molecular no)ethylene). The lH NMR spectra show the resonances cation peak, although in every spectrum the [M - XI’ of both ligands in the correct ratio (Experimental peak appears a t m l z (%) 749 (541, 795 (381, 841 (701, Section). Complexes 4-8 were characterized by posi763 (721,808 (loo), 855 (1001,777 (lo), 823 (41, and 869 tive-ion FAB mass spectrometry. In all cases the parent (12), respectively. The crystal structure of complex 10 has been deter(12) Lin, I. J. B.; Liu, C. W.; Liu, L. K.; Wen, Y. S. Organometallics mined by X-ray crystallography (Figure 2). The asym1992.11. 1447. metric unit consists of two molecules of 10 and two (13)Gbwda, M. N.; Naikar, S. B.; Reddy, G. K. N. Adv. Inorg. Chem. Radwchem. 1984,28,255. (14) Cerrada, E.;Jones, P. G.; Laguna,A,; Laguna, M. J. Chem. Soc., Dalton Trans. 1994, 1325. (151Dbvila, R. M.; Staples, R. J.; Fackler, J. P., Jr. Organometallics 1994, 13, 418.
(16)Us6n, R.;Laguna, A,; Laguna, M.; Fraile, M. N.; Jones, P. G.; Sheldrick, G. M. J. Chem. SOC.,Dalton Trans. 1986, 291. (17) Bardaji, M.;Gimeno, M. C.; Jones, P. G.; Laguna, A.; Laguna, M.Organometallics 1994, 13, 3415.
Au(I) and Au(II) Complexes with Xanthate Ligands Table 4. Atomic Coordinates ( x 104) and Equivalent Isotropic Displacement Parameters (A2x 103) for 1W X
Y
Z
2430.3 (4) 419.5 (4) 4430.6 (11) -1513.9 (10) -388 (3) 1677 (3) 2484 (3) -122 (8) 978 (9) 3168 (10) 388 (11) 417 (15) 2725 (10) 2024 (1 1) 2204(11) 3058 (1 1) 3747 (1 1) 3593 (10) 3088 (10) 3009(11) 3565 (13) 4160 (13) 4226 ( 12) 3673 (12) 7582.1 (4) 8148.7 (4) 6935.2 (12) 8695.4 (12) 8970 (3) 10060 (3) 5514 (3) 10956 (7) 6392 (9) 6481 (11) 10042 (9) 12003 (12) 4486 (10) 3339 (11) 2627 (12) 3044 (11) 4183 (12) 4918 (11) 4701 (10) 4445 (12) 3783 (12) 3344 (13) 3596 (12) 4278 (1 1) 2331 (25) 3782 (7) 1582 (12) 9520 (33) 9121 (11) 9665 (10)
6396.1 (4) 5866.8 (4) 6969.4 (10) 5273.3 (10) 4075 (2) 5166 (3) 8330 (2) 3164 (7) 7420 (10) 7458 (9) 4102 (10) 3084 (13) 9196 (9) 9732 (10) 10426 (10) 10569 (11) 10035 (10) 9360 (9) 9241 (9) 8719 (10) 9400 (12) 10546 (11) 11059 (11) 10405 (10) 4393.6 (4) 6333.0 (4) 2508.5 (10) 8211.8 (11) 5129 (3) 7121 (3) 4375 (3) 6780 (7) 3662 (10) 5804 (9) 6386 (9) 7813 (12) 3873 (10) 3662 (12) 3369 (13) 3278 (1 1) 3495 (12) 3819 (11) 4198 (9) 3291 (11) 3143 (12) 3900(11) 4812 (11) 4963 (1 1) 136 (25) 560 (6) 428 (15) 9753 (30) 8793 (8) 10963 (8)
3783.6 (3) 4127.7 (3) 3503.1 (9) 4537.3 (8) 3007 (2) 2277 (2) 5373 (2) 1516 (5) 5162 (8) 5117 (7) 2218 (8) 747 (9) 4692 (8) 4638 (8) 4116 (9) 3653 (9) 3699 (8) 4226 (8) 6537 (8) 7179 (8) 8094 (8) 8339 (9) 7701 (8) 6794 (8) 1587.6 (3) 2762.5 (3) 385.7 (8) 3937.3 (9) 809 (2) 2573 (2) 2419 (2) 1199 (5) 2265 (7) 3029 (8) 1537 (7) 1742 (10) 3066 (8) 2837 (9) 3414 (10) 4198 (8) 4426 (9) 3884 (9) 1351 (7) 583 (8) -222 (9) -256 (8) 494 (8) 1304 (8) 136 (19) 1083 (8) 768 (11) 2326 (24) 1367 (6) 2643 (10)
26.5 (1) 25.6 (1) 38.2 (3) 31.0 (3) 32.6 (7) 33.7 (7) 29.2 (6) 43 (2) 31 (3) 28 (2) 31 (2) 54 (4) 34 (2) 41 (2) 43 (3) 43 (3) 37 (2) 36 (2) 32 (2) 42 (3) 53 (4) 51 (3) 49 (3) 42 (3) 25.8 (1) 26.5 (1) 39.6 (3) 43.4 (3) 33.5 (7) 33.9 (7) 29.7 (7) 40 (2) 26 (2) 34 (3) 26 (2) 54 (4) 35 (2) 51 (3) 55 (3) 45 (3) 48 (3) 43 (3) 32 (2) 46 (3) 51 (3) 48 (3) 44 (3) 39 (3) 129 (9) 196 (5) 270 (7) 175 (13) 188 (4) 224 (6)
Organometallics, Vol. 14, No. 3, 1995 1313 Table 5. Selected Bond Lengths (A) and Angles (deg) for 10 2.075 (11) 2.510 (2) 2.100 (12) 2.5178 (14) 1.693 (12) 1.770 (11) 1.804 (13) 1.48 (2) 2.348 (3) 2.5710 (11) 2.357 (3) 1.700 (12) 1.763 (1 1) 1.801 (11) 1.329 (13)
Au( 1)-C(2) Au( 1)-Br( 1) Au(2)-C( 1) Au(2)-Br(2) W)-C(3) P(l)-C(l) P( 1)-C(21) o(wc(4) Au( 1’)-S(1’) Au(l’)-Au(2’) Au(2’)-S(2’) S(l’)-C(3’) P(l’)-C(2’) P(l’)-C(21’) O(l’)-C(3’) C(2)-Au( 1)-S(2) S(2)-Au( 1)-Br( 1) S (2)-Au( 1)-Au(2) C(l)-Au(2)-S(l) S( l)-Au(2)-Br(2) S( l)-Au(2)-Au( 1) C(3)-S( l)-Au(2) C(2)-P( 1)-C( 1) C(l)-P(l)-C(ll) C(l)-P(l)-C(21) C(3)-O( 1)-C(4) P( l)-C(2)-Au( 1) O(1)-C(3)-S(2) C( 1‘)-Au( 1’)-S( 1’) S( 1’)- Au( 1’)-Br( 1’) S( I’)-Au( 1’)- Au(2’) C(2’)-Au(2‘)-S(2’) S(2’)-Au(2’)-Br(2’) S( 2’)-Au(2’)-Au( 1’) C(3’)-S( l’)-Au( 1’) C(2’)-P( l’)-C( 1’) C(l’)-P(l’)-C(21’) C(l’)-P(l’)-C(ll’) C(3’)-O( l’)-C(4? P( l’)-C(2’)-Au(2’) O(l’)-C(3’)-S( 1’)
176.9 (3) 87.60 (9) 94.49 (8) 174.2 (3) 87.48 (9) 91.98 (8) 109.8 (4) 106.2 (6) 111.1 (6) 111.3(5) 118.3 (10) 108.5 (5) 121.2 (9) 176.2 (3) 86.49 (9) 93.76 (8) 173.7 (3) 87.24 (9) 93.35 (8) 107.8 (4) 106.2 (6) 110.7 (5) 112.2 (5) 120.4 (9) 113.8 (6) 111.8 (8)
Au( 1)-S(2) Au(1)-A~(2) Au(2)-S( 1) s(1)-c(3) P(l)-C(2) P(l)-C(ll) 0(1)-c(3) Au( 1’)-C( 1’) Au( 1’)-Br( 1’) Au(2’)-C(2’) Au(2’)-Br(2’) S(2’)-C(3’) P(l’)-C(l’) P(1’)-C(l1’) O(l’)-C(4’) C(2)-Au( 1)-Br( 1) C(2)-Au( 1)-Au(2) Br(1)-Au( 1)-Au(2) C( 1)-Au(2)-Br(2) C( l)-Au(2)-Au( 1) Br(2)-Au(2)-Au( 1) C(3)-S(2)-Au( 1) C(2)-P(l)-C(ll) C(2)-P( 1)-C(21) C(1l)-P(l)-C(21) P(1)-C( 1)-Au(2) 0(1)-C(3)-S( 1) S( l)-c(3)-s(2) C( 1’)-Au( 1’)-Br( 1’) C( 1’) - Au(1 ’) -Au(2’) Br(1’)-Au( 1’)-Au(2’) C(2’)-Au(2’)-Br(2’) C(2’)-Au(2’) -Au( 1’) Br(2‘)-Au(2’)-Au(l’) C(3’)-S(2’)-Au(2’) C(2’)-P( l’)-C(21’) C(Y)-P(l’)-C(ll’) C(21’)-P(l’)-C(ll’) P( 1’)-C( 1’)- Au( 1’) O(l’)-C(3’)-S(2’) S(2’)-C(3’)-S(lf)
2.351 (3) 2.5660 (10) 2.346 (3) 1.693 (12) 1.753 (12) 1.793 (12) 1.314 (14) 2.067 (11) 2.516 (2) 2.111 (13) 2.516 (2) 1.678 (11) 1.776 (10) 1.808 (12) 1.46 (2) 90.0 (3) 87.9 (3) 177.89 (4) 86.7 (3) 93.8 (3) 175.69 (3) 107.0 (4) 110.8 (5) 109.3 (5) 108.1 (5) 113.2 (6) 112.0 (9) 126.8 (7) 90.9 (3) 89.0 (3) 176.63 (4) 86.5 (3) 92.9 (3) 178.78 (4) 107.9 (4) 111.3 (5) 108.3 (6) 108.1 (5) 107.6 (5) 119.8 (9) 128.3 (7)
molecules of dichloromethane. As in 3,the structure consists of an eight-membered dimetallacycle in which the two gold atoms are doubly bridged by a xanthate and a bis(y1ide)ligand. The C-Au-S angles lie in the range 173.7-176.9(3)”, slightly smaller than that in 3. In addition, the “envelope”has become a twisted conformation, probably because of the Au-Au bond formation upon oxidation. The Au-Au distances are 2.566(1) and 2.5710(11) A, shorter than in the symmetrical [Au2@-(CH2)2PPh2)2Br2118 (2.614(1)A)and close to that found in the analogous complex [Auz@-(CHz)2PPhz){pS2CN(CH2Ph)2}Br2I1’ (2.5653(10)A). There are inter-
molecular contacts between gold atoms (Au(2)Au(2’;-1+X J A ) , 3333 A; Au(~ ) A u2;(-x, 1-y, 1-z), 4.121A) and between gold and bromine (Au(2)Br(2;-x,l-y,lz ) 3.472 A; Au(2’;-l+xyp)Br(2), 3.597 A). The Au-Br bond lengths range from 2.510(2) to 2.518(1) A similar to those in [ A U Z @ - ( C H ~ ) ~ P P ~ ~ ) Z B ~ Z I )~B~~I~~ (2.516(1) or in ( N B U ) ~ [ A ~ ~ + - M N T (2.510(8) “he values do not display the unexpected difference observed in [Au~~-(CH~)~PPh~}{pu-S~CN~CH~Ph~~ (2.5022(14)and 2.5253(14) A). The Au-S bond lengths (2.346(3)-2.357(3)A) are longer than in 3 and marginally longer than in [A~Z@-(CH~)ZPP~~)@-S~CN(CH~P~)~)Brp] (2.337(3) and 2.338(3) A), in which an elongation of the Au-S distances as one goes from dithiocarbamate-gold(1) to -gold(II) derivatives had already been remarked upon. The Au-C distances 2.067(11)-2.111(13) A are similar to those found in other gold(I1) ylide complexes. The coordination around the gold atoms is essentially square planar. The chains Br-Au-Au-Br are almost linear; Br-Au-Au angles are 175.69(3)178.78(4)”. The reaction of the cationic complexes 4-8 with halogen proceeds in a different way; the gold(I1) derivatives are not obtained and the 31P{1H} NMR spectra show a mixture of products, including the starting material. In the case of 4 and 5 with chlorine,
(18)Us6n, R.; Laguna, A.; Laguna, M.; J i m h e z , J.;Jones, P. G. J. Chem. Soc., Dalton Trans. 1991,1361.
(19)Khan, N. I.; Wang, S.; Fackler, J. P., Jr. Inorg. Chem. 1989, 28,3579.
See footnote a in Table 2
A).
A)
~~
1314 Organometallics, Vol. 14, No. 3, 1995
Bardaji et al.
[A~Z(~~-SZCOR)(~-(PP~Z)ZY}IC~O~ (Y = CHZ,R = Me (4), the previously described complexes [Au3Clz@-(PPhz)zCHz}zlC104 and [ ( A ~ C ~ ) ~ { ~ - ( P P ~ Zwere ) Z CdeH Z ~ I Et ~ ~(5); ~ ~Y~ = CH2CHa, R = Me (61,Et (7), 'Pr (8)). To a solution of [AU~O~-(PP~Z)ZY}ZI(C~O~)Z~~'~~ (0.05 mmol; X = CHZ tected by 31P{ lH}NMR. (0.068 g), CH2CH2 (0.069 g)) in dichloromethane (40 mL) was These results can be rationalized by considering that added the stoichiometric amount of [AU,(U-SZCOR),,I(R = Me strongly a-donating ligands, such as bidylide), should (0.030 g), Et (0.032 g), 'Pr (0.033 g)). After the mixture was support oxidative addition much better than weaker stirred for 5 h (4) or 2 h (5-8),the solution was filtered. a-donating and stronger n-accepting ligands.22 This Concentration of the filtered solution to ca. 5 mL and addition of diethyl ether led to precipitation of 4-8. Solids were washed could be the reason the combination of bis(y1ide) and with diethyl ether (2 x 5 mL). 4: yield 82%; mp 240 "C dec; xanthate, but not diphosphine and xanthate, yields goldlH NMR 6 7.79-7.33 (m, 20H, Ph), 4.33 (s, 3H, Me), 4.19 (t, (11) derivatives. Moreover, the positive charge of the 2H, J(PH) = 12.4 Hz, PCHzP); AM= 110 S2-' cm2 mol-'. 5: diphosphine complex, in contrast to the neutral charyield 72%;mp 160 "C; 'H NMR 6 7.80-7.33 (m, 20H, Ph), 4.69 acter of the xanthate-bis(y1ide) pair, could be an (4, 2H, J(HH) = 7.1 Hz, CH2-0), 4.19 (t, 2H, J(PH) = 12.5 additional reason; very few cationic gold(I1)complexes Hz, PCHzP), 1.42 (t, 3H, CH3); AM= 111 8-1cm2 mol-l. 6: are known. yield 94%; mp 202 "C; lH NMR 6 7.81-7.50 (m, 20H, Ph), 4.36 (s, 3H, Me), 3.10 ("d,4H, J(PH) = 12.4 Hz, PCH2CH2P); AM = 130 8-1cm2 mol-'. 7: yield 78%; mp 218 "C; 'H NMR 6 Experimental Section 18323
7.83-7.51 (m, 20H, Ph), 4.72 (9, 2H, J(HH) = 7.1 Hz, CH20),3.10 ("d", 4H, J(PH) = 12.2 Hz, PCH~CHZP), 1.58 (t, 3H, General Data. IR spectra were recorded on a PerkinCH3);AM= 127 S2-' cm2 mol-'. 8: yield 72%; mp 190 "C; 'H Elmer 559 or 883 spectrophotometer, over the range 4000N M R 6 7.81-7.50 (m, 20H, Ph), 5.53 (sept, l H , J(HH) = 6.0 200 cm-', by using Nujol mulls between polyethylene sheets. Hz, CH-O), 3.09 (br, 4H, PCHZCHZP),1.56 (d, 6H, Me); AM= lH and 31PNMR spectra were measured on a Varian UNITY 103 S2-1 cm2 mol-l. 300 in CDCl3 solutions; chemical shifts are quoted relative t o SiMe4 ('H) and H3P04(external, 31P). C, H, and N analyses [AuZ{p-(CH2)2PPh2}(/r-S2COR)X~I (R= Me, X = C1 (9), were performed with a Perkin-Elmer 2400 microanalyzer. Br (lo),I (11);R = Et, X = C1(12), Br (13),I(14);R = 'Pr, Conductivities were measured in acetone solution with a X = C1 (15),Br (161,I (17)). To a solution of [Auz{p-(CHz)zPhilips PW 9509 apparatus. Melting points were measured PPhz}(U-SzCOR)](0.1 mmol; 1 (0.071 g), 2 (0.073 g), 3 (0.074 on a Buchi apparatus and are uncorrected. Mass spectra were g)) in dichloromethane (20 mL) was added the stoichiometric recorded on a VG Autospec using FAB+ techniques. amount of halogenX2 (0.1 mmol; X2 = Clz, Brz, in CCL solution; 12, 0.025 g). m e r the mixture was stirred for about 20 min Electrochemical studies were carried out using an EG and at room temperature, the solution was concentrated to ca. 5 G Model 273 potentiostat, in conjunction with a three-electrode mL. Addition of diethyl ether (20 mL) afforded complexes cell. The auxiliary electrode was a platinum wire, and the 9-17. Solids were washed with diethyl ether (2 x 5 mL). 9: working electrode was a platinum bead. The reference was yield 77%; mp 148 "C dec; 'H NMR (not included in Table 1) an aqueous saturated calomel electrode (SCE) separated frum 6 7.74-7.54 (m, 10H, Ph), 4.22 (s, 3H, Me); AM= 3 S2-I cm2 the test solution by a fine-porosity frit and an agar bridge mol-l. 10: yield 80%; mp 124 "C dec; 'H NMR 6 7.74-7.53 M in saturated with KC1. CHzClz solutions were 5 x (m, 10H, Ph), 4.22 (s, 3H, Me); AM = 4 S2-I cm2 mol-l. 11: complex and 0.1 M in [NB&][PF6] as the supporting electroyield 90%; mp 130 "C dec; 'H NMR 6 7.71-7.63 (m, 10H, Ph), lyte. 4.19 (s, 3H, Me); AM= 3 S2-l cm2 mol-'. 12: yield 89%; mp C, H, and N analyses and 31P{1H}and some 'H NMR data 146 "C; lH NMR 6 7.75-7.56 (m, 10H, Ph), 4.59 (q,2H, J(HH) are listed in Table 1. All reactions were carried out at room = 7.1 Hz, CHz-O), 1.46 (t, 3H, CH3); AM= 5 S2-I cm2 mol-'. temperature. 13: yield 90%; mp 120 "C dec; lH NMR 6 7.73-7.53 (m, 10H, Syntheses. [AUZ{~-(CHZ)~PP~Z)(~~-SZCOR)I (R= Me (l), Et (2), 'Pr (3)). To a solution of [ A U ~ O ~ - ( C H ~ ) ~ (0.123 P P ~ Z } ~ I Ph), ~ ~ 4.57 (9, 2H, J(HH) = 7.1 Hz, CH2-O), 1.44 (t, 3H, CH3); AM = 3 S2-I cm2 mol-'. 14: yield 83%; mp 98 "C dec; lH NMR g, 0.15 mmol) in dichloromethane (40 mL) was added the 6 7.71-7.52 (m, 10H, Ph), 4.55 (q, 2H, J(HH) = 7.1 Hz, CH2stoichiometric amount of [AU,(U-SZCOR),I(obtained by addi01, 1.44 (t, 3H, CH3); AM= 2 8-'cm2 mol-'. 15: yield 70%; tion of [AuCl(tht)lZ4to an alcoholic KSzCOR solution4) (R = mp 163 "C dec; lH NMR 6 7.76-7.37 (m, 10H, Ph), 5.45 (sept, Me, 0.092 g (1);R = Et, 0.096 g (2); R = 'Pr, 0.099 g (3)).After lH, J(HH) = 6.1 Hz, CH-0), 1.43 (d, 6H, Me); AM= 2 S 2 - I the suspension was stirred for about 6 h, the solution was cm2 mol-l. 16: yield 73%; mp 162 "C dec; lH NMR 6 7.80filtered off t o remove the unreacted starting material. Then 7.37 (m, 10H, Ph), 5.44 (sept, l H , J(HH) = 6.1 Hz, CH-O), the clear solution was evaporated t o ca. 5 mL. Addition of 1.43 (d, 6H, Me); AM= 4 S2-l cm2 mol-'. 17: yield 78%; mp diethyl ether led to precipitation of 1-3. Solids were washed 110 "C; 'H NMR 6 7.71-7.47 (m, 10H, Ph), 5.41 (sept, l H , with diethyl ether (2 x 5 mL). 1: yield 80%; mp 194 "C dec; J(HH) = 6.1 Hz, CH-O), 1.41 (d, 6H, Me); AM= 23 S2-I cm2 lH NMR (not included in Table 1)6 7.83-7.39 (m, 10H, Ph), mol-'. 4.13 (s,3H, Me); AM= 1S2-l cm2mol-l. 2: yield 85%; mp 175 X-ray Structure Determination of Compounds 3 and "C; 'H NMR 6 7.83-7.44 (m, 10H, Ph), 4.49 (9,2H, J(HH) = 10. Crystals were mounted on glass fibers in inert oil and 7.1 Hz, CHz-O), 1.42 (t, 3H, CH3); AM= 1 S2-I cm2 mol-'. 3: transferred t o the cold gas stream of the diffractometer yield 78%; mp 160 "C;lH NMR 6 7.81-7.43 (m, 10H,Ph), 5.40 (Siemens R3 with LT-2 low temperature attachment). Data (sept, l H , J(HH) = 6.2 Hz, CH-0), 1.38 (d, 6H, Me); AM= 1 were collected at -100 "C in the w-scan mode using monoS2-I cm2mol-l. Other mass spectra peaks at m l z (%) 517 (50, chromated Mo Ka radiation (1 = 0.710 73 & t o 20" = 50". 1) and 545 (12, 3)are due to [M - Au]+. Cell constants were refined from setting angles of ca. 50 reflections in the 20 range 20-23". Absorption corrections (20) U s h , R.; Laguna, A.; Laguna, M.; Fernhdez, E.; Villacampa, were based on li,scans. Structures were solved with the heavyM. D.; Jones, P. G.; Sheldrick, G. M. J. Chem. Soc., Dalton Trans. 1983, atom method and refined anisotropically on F.26Hydrogen 1679. (21) Schmidbaur, H.; Wohlleben, A.; Wagner, F.; Orama, 0.; Huttatoms were included as rigid methyl groups or using a riding ner, G. Chem. Ber. 1977, 110, 1748. model. (22) Schmidbaur, H. Acc. Chem. Res. 1975, 8 , 62. (23) (a) Vicente, J.; Chicote, M. T.; Saura-Llamas, I. J . Chem. Soc., Dalton Trans. 1090, 1941. (b) Laguna, A.; Laguna, M.; JimBnez, J.; Lahoz, F. J.; Olmos, E. J.Orgummet. Chem. 1992,435,235.(c) Bardaji, M.; Blasco, A.; JimBnez, J.; Jones, P. G.; Laguna, A.; Laguna, M.; Merchh, F. Inorg. Chim. Acta 1994,223, 55. (24) Us6n, R.; Laguna, A.; Laguna, M. Inorg. Synth. 1989, 26, 85.
(25) Schmidbaur, H.; Wohlleben, A.; Schubert, U.; Frank, A.; Huttner, G. Chem. Ber. 1977,110, 2751. (26) Sheldrick, G. M. SHEEZ-93: A Program for Crystal Structure Refinement (prerelease version 1992); University of Gottingen, Gattingen, Germany.
Organometallics, Vol. 14, No. 3, 1995 1315
Au(I) and Au(II) Complexes with Xanthate Ligands Compound 3: monoclinic, space group P21/c,a = 8.571(3)
A, b = 10.219(4)A, c = 23.210(6) A, /3 = 97.37(3)",V = 2016.1
A3,Z = 4, ,u = 14.8 mm-l, D,t1 = 2.446 Mg m-3; pale brown tablet cut to 0.8 x 0.25 x 0.1 mm, 6108 reflections, 3566 independent (Rbt 0.061); 219 parameters, 150 restraints, R,(F) = 0.097, R(F,>4a(F)) = 0.033, S = 1.05, maximum Ag = 2.3 e A-3. Compound lWH2C12: triclinic, space group Pi, a = 12.917(4)A, b = 13.864(3)A, c = 15.975(5)A, a = 106.05(2)", /3 = 96.27(2)", y = 113.78(2)",V = 2435.5 A3, 2 = 4, ,u = 15.8 mm-l, D,tl = 2.616 Mg m-3; orange prism 0.5 x 0.3 x 0.15 mm, 10 360 reflections, 8618 independent (Rht = 0.024); 479 parameters, 296 restraints, R,(F) = 0.112, R(F,>4dF)) = 0.040, S = 1.01, maximum Ag = 1.8 e A-3.
Acknowledgment. We thank the Direccidn General de Investigacidn Cientifica y Tecnica (No. PB91-0122) and the Fonds der Chemischen Industrie for financial support and Ministerio de Educacidn y Ciencia for a grant (to M.B.). SupplementaryMaterial Available: Descriptions of the crystal structure determinations, including tables of crystal data, data collection, and solution and refinement parameters, atomic coordinates of H atoms, bond distances and angles, and thermal parameters (10 pages). Ordering information is given on any current masthead page. OM940733Q
