STUDIES ON THE COMPLEX (5)-7,9-C2B9H10[C(H)C(6)H(4)ME-4]-10)(CO)(PPH(3))] - CRYSTAL-STRUCTURE OF THE COMPOUND TA(5)-7,9-C2B9H10[C(H)(C(6)H(4)ME-4)(PET(3))]-10)]

Treatment of CO-saturated CH2Cl2 solutions of [NEt(4)][Rh(CO)(PPh(3))( eta(5)-7,9-C2B9H11] with n(=CC(6)H(4)Me-4)(CO)(2)(eta(5)-C(5)H(4)Me)][ BCl4] affords the complex a(5)-7,9-C2B9H10[C(H)C(6)H(4)Me-4]-10}(CO)(P PH3)]. The latter reacts with K[BH(CHMeEt)(3)] in the presence of [NEt (4)]Cl to yield [NEt(4)][Rh(CO)(PPh(3)){eta(5)- 7,9-C2B9H10-(CH(2)C(6) H(4)Me-4)-10}], and with tertiary phosphines (L = PMe(3), PEt(3), or P Me(2)Ph) to give the zwitterionic complexes ){eta(5)-7,9-C2B9H10-[C(H) (C(6)H(4)Me-4)(L)]-10}]. The crystal structure of the product with L = PEt(3) has been determined, thereby firmly establishing the structure of this class of complex. The reaction between [AuCl(PPh(3))] and the species with L = PMe(3) in the presence of TIBF4 affords the dimetal compound [RhAu(CO)(PPh(3))(2){eta(5)-7,9-C2B9H10[C(H)(C-6 H(4)Me-4)(PM e(3))]-1O}][BF4]. The NMR spectra of the new compounds are reported, a nd discussed in relation to their structures.