Inorg. Chem. 1992, 31, 1823-1826
1823
Contribution from the Department of Chemistry, McGill University, 801 Sherbrooke Street West, Montreal, Quebec, Canada H3A 2K6
Possible Cooperative Bonding between the Ru-Bonded and the S-Bonded SO2 Groups in CpRu(PPh,) (SO,) (S(S02)-4-CJ-f4Me) Alan Shaver* and Pierre-Yves Plouffe’ Received September 19, 1991 The complexes CpRu(PPh3)2SR,where R = 4-C6H4Me,1-C3H7,and CHMe2, react with SO2to give two types of products; one, CpRu(PPh3)2(S(S02)R),possesses a labile S-bonded SO2group, and the other type, CpRu(PPh3)(S02)(S(S02)R),possesses both was S-bonded and Ru-bonded SO2grou s neither of which are labile. The structure of CpRu(PPh3)(S02)(S(S02)-4-C6H5Me) determined: pZl/C, a = 9.954 (2) b = 18.423 (5) A, c = 16.111 (4) A, @ = 95.13 (2)O, V = 2942.6 A’, and Z = 4. During the initial stages of the reaction, complexes with two SO2 groups are favored at low SO2 concentrations, while those with only S-bonded SO2are favored at high concentrations. This observation and the differences in the relative ease of SO2loss between the two types of complexes is discussed in terms of cooperativity between the two SO,groups. This leads to reduced lability of the S-bonded SO2group when the complex contains a Ru-bonded SO2 ligand (or a CO ligand).
1,
Introdllction Interest in the transition metal chemistry of sulfur oxides in general, and SO2 in particular, remains high. Environmental concerns about SO2in the atmosphere spurs studies into potential fixing reactionsa2 The SO2molecule shows a broad and diverse range of reactivity and types of bonding with complexes3 that illustrates many fundamental concepts. The molecule can enter the coordination sphere as a ligand much like CO. It can also form Lewis acid adducts with a free lone pair of a coordinated ligand atom such as iodide. The insertion reactions4of SO2into metal-carbon bonds have been well studied. As part of a research program on complexes containing catenated polysulfur and polysulfur oxide ligands, we have prepared complexes of the type CpRu(PPh,)(CO)E, where E = SJt,5where x = 1-3, and E = SS(O),R,6 where n = 1 and 2. The parent complexes C ~ R U ( P P ~ , ) ~ Sare R ~activated ” with respect to loss of PPh3,easily forming CpRu(PPhJ(CO)(SR) or, in the absence of additional ligands, trimers’ of the type [CpRuSR],. In the presence of CS2,insertionSainto the Ru-S bond occurs to give the thioxanthates CpRu(PPh3)(S2CSR). Thus, the complexes C P R U ( P P ~ ~ ) ~are S Rexcellent candidates for reaction with SO2 via substitution of PPh3. Moreover, Kubass has shown that certain transition metal thiolates form labile adducts with SO2at the sulfur atoms. We have observed labile adduct formation9 at the sulfur atom of CpW(CO),(PPh,)SR. Finally, there are reports’O of SO2 insertion into metal-nitrogen and metal-oxygen bonds which raise the interesting possibility of insertion into M-SR bonds. We report here the rich chemistry” of the thiolato complexes CpRu(1) Resent address: National Research Council, Institute of Environmental
Chemistry, Montreal Road, Ottawa, Ontario, Canada KIA OR6. (2) (a) Kubas, G.J.; Ryan, R. R. Inorg. Chem. 1984,23,3181. (b) Kubas, G.J.; Wasserman, H. J.; Ryan, R. R. Organometallics 1985,4,2012. (c) Kubas-Martin, K. A.; Kubas, G.J.; Ryan, R. R. Organometallics 1989.8.1910. (d) Kubas. G.J.: Ryan. R. R. Polvhedron 1986.5.473. (e) Kubas, G.J.; Ryan, R.R. J. Am. Chem. Soc.~1985,107,6138.(f) Kubas, G. J.; Wasserman, H. J.; Ryan, R. R. Organometallics 1985, 4,419. (g) Lorenz, LP.; Walter, G.;Hiller, W. Chem. Eer. 1990,123, 979. (h) Neher, A,; Lorenz, I.-P. Angew. Chem., Inf.Ed. Engl. 1989, 28, 1342. (i) Farrar, D. H.; Guhthasan, R. R. J . Chem. Soc., Dalton Trans. 1989, 557. (a) Schenk, W. A. Angew. Chem., Int. Ed. Engl. 1987, 26, 98 and references therein. (b) Kubas, G.J. Inorg. Chem. 1979, 18, 182 and references therein. Wojcicki, A. Adu. Organomet. Chem. 1974, 12, 31. (a) Shaver, A.; Plouffe, P.-Y.; Bird, P.; Livingstone, E. Inorg. Chem. 1990,29, 1826. (b) Shaver, A,; Plouffe. P.-Y. Manuscript in preparation. Shaver, A.; Plouffe, P.-Y. J . Am. Chem. Soc. 1991, 113, 7780. Shaver, A.; Plouffe, P.-Y.; L i b , D.; Singleton, E. Inorg. Chem. 1992, 31, 997. Eller, P. G.;Kubas. G.J. J . Am. Chem. SOC.1977, 99, 4346. Shaver, A.; Lum, B. S. Unpublished results. However X-ray structural confirmation is not included in these reports: (a) Wenschuh, E.; Zimmering, R. Z . Chem. 1988,28,190. (b) Alcock, N. W.; Platt, A. W. G.;Powell, H. H.; Pringle, P. G. J. Organomet. Chem. 1989, 361,409. Some of the results reported herein have appeared: Shaver, A.; Plouffe, P.-Y. Third Chemical Conference of North America, Toronto, 1988, June 5-10.
Table I. Crystallographic Data for
CpRu(PPh3)(S02)(S(S02)-4-C6H4Me) (20) chem formula C3,,H2,04PRuS3 fw = 676.73 a = 9.954 (2) A b = 18.423 ( 5 ) A c = 16.111 (4) A @ = 95.13 (2)O V = 2942.6 (12) A3 2 1 4
space group: R , / c T = 20 1 oc X = 1.54056 A pmM = 1.528 g p(Cu Ka) = 7.18 mm-’ R = 0.062, RWb= 0.057
*
Table 11. Positional Parameters and Isotropic Thermal Parameters (A2) for C~RU(PP~~)(SO~(S(S~~)-~-C~H~M~) Ru S(1) S(2) S(3) P 0(1) O(2) O(3) O(4) C(l) C(2) C(3) C(4) C(5) C(6) C(7) C(8) C(9) C(10) C(11) C(12) C(13) C(14) C(15) C(16) C(17) C(18) C(19) C(20) C(21) C(22) C(23) C(24) C(25) C(26) C(27) C(28) C(29) C(30)
X
V
0.06569 (7) 0.11166 (25) 0.0982 (3) 0.0482 ( 5 ) 0.29254 (24) 0.2128 (7) -0.0077 (8) 0.1218 (15) -0.0832 (12) 0.5067 (10) 0.5616 (12) 0.4816 (12) 0.3461 (12) 0.2885 (10) 0.3673 (9) 0.3470 (10) 0.3490 (12) 0.3157 (14) 0.2771 (12) 0.2717 (10) 0.3049 (9) 0.4461 (10) 0.5378 (13) 0.6041 (12) 0.5736 (13) 0.4835 (13) 0.4147 (9) -0.0052 (IO) -0.0277 (IO) -0.1217 (11) -0.1546 (10) -0.0803 (11) -0.0207 (1 1) -0.1098 (13) -0.1979 (12) -0.1913 (10) -0.1041 (11) -0.0147 (10) -0.2966 (12)
0.35464 (4) 0.22874 (14) 0.38191 (15) 0.15372 (23) 0.37175 (14) 0.3705 (5) 0.4202 (4) 0.0903 (7) 0.1437 (10) 0.4628 (6) 0.5262 (7) 0.5843 (6) 0.5770 (6) 0.5134 (6) 0.4551 ( 5 ) 0.4489 (6) 0.4568 (8) 0.4011 (10) 0.3365 (8) 0.3270 (6) 0.3839 (6) 0.2914 (7) 0.2412 (8) 0.1958 (7) 0.2067 (7) 0.2600 (7) 0.3008 ( 5 ) 0.4257 (7) 0.3548 (7) 0.3255 (7) 0.3824 (8) 0.4425 (6) 0.1137 (6) 0.0773 (6) 0.1161 (7) 0.1908 (7) 0.2282 (6) 0.1872 (6) 0.0767 (7)
z
-b1.0
0.63700 ( 5 ) 2.57 (3) 0.62128 (17) 3.32 (12) 0.51244 (17) 3.34 (12) 0.76701 (24) 7.15 (23) 0.68744 (16) 2.72 (1 1) 0.4692 (4) 6.7 (5) 0.4603 (5) 5.5 (4) 0.7496 (8) 14.4 (11) 0.7543 (9) 19.7 (13) 0.6529 (7) 4.4 (6) 0.6286 (9) 5.8 (7) 0.6044 (7) 4.7 (6) 0.6023 (7) 5.0 (6) 0.6247 (7) 3.9 ( 5 ) 0.6502 (6) 2.9 (4) 0.8371 (7) 3.9 ( 5 ) 0.9235 (8) 5.8 (8) 0.9730 (8) 6.2 (9) 5.7 (8) 0.9367 (8) 0.8508 (7) 4.1 (6) 0.7998 (6) 3.2 ( 5 ) 0.5855 (7) 4.5 (6) 0.5655 (8) 6.2 (7) 5.4 (7) 0.6290 (10) 0.7088 (9) 6.7 (8) 0.7304 (7) 5.4 (6) 0.6670 (7) 3.2 ( 5 ) 0.7326 (7) 4.5 (6) 0.7543 (7) 3.9 (6) 0.6952 (7) 4.5 (6) 0.6315 (8) 5.5 (7) 0.6572 (8) 4.5 (6) 0.5488 (8) 4.2 (6) 0.4928 (8) 5.0 (7) 0.4343 (8) 4.5 (6) 0.4375 (7) 4.2 (6) 0.4941 (7) 3.8 ( 5 ) 0.5509 (6) 3.2 ( 5 ) 5.3 (3) 0.3663 (7)
“Ei, is the mean of the principal axes of the thermal ellipsoid. (PPh3)$R with SO2 which has resulted in the isolation and structural characterization of CpRu(PPh3)(S02)(S(S02)-4-
0020-1669/92/1331-1823%03.00/00 1992 American Chemical Society
1824 Inorganic Chemistry, Vol. 31, No. 10, 1992
Shaver and Plouffe ~_____
comp1ex 28, R = 4-C6H,Me 2b, R = l-C;H,
CSHS 5.01 4.94
Zc, R = CHMe,
5.06
3s 3b 3ck
4.48 4.60 4.77
CH3 2.09
CHMe,
C6H4
CH2CH2CHI
CH2CH2CH3
2.33< 2.46
