화학공학소재연구정보센터
Inorganic Chemistry, Vol.47, No.13, 6090-6104, 2008
Synthesis, structural characterization, and ligand replacement reactions of gem-dithiolato-bridged rhodium and iridium complexes
The reaction of gem-dithiol compounds R2C(SH)(2) (R = Bn (benzyl), Pr-i; R-2 = -(CH2)(4)-) with dinuclear rhodium or iridium complexes containing basic ligands such as [M(mu-OH)(cod)](2) and [M(mu-OMe)(cod)](2), or the mononuclear [M(acac)(cod)] (M = Rh, Ir, cod = 1,5-cyclooctadiene) in the presence of a external base, afforded the dinuclear complexes [M-2(mu-S2CR2)(cod)(2)] (1-4). The monodeprotonation of 1,1-dimercaptocyclopentane gave the mononuclear complex (Rh(HS(2)Cptn)(cod)] (5) that is a precursor for the dinuclear compound [Rh-2(mu-S(2)Cptn)(cod)(2)] (6). Carbonylation of the diolefin compounds gave the complexes [Rh-2(mu-S2CR2)(CO)(4)] (7-9), which reacted with P-donor ligands to stereoselectively produce the trans isomer of the disubstituted complexes [Rh-2(mu-S2CR2)(CO)(2)(PR'(3))(2)] (R' = Ph, Cy (cyclohexyl)) (10-13) and [Rh-2(mu-S2CBn2)(CO)(2){P(OR')(3)}(2)] (R' = Me, Ph) (14-15). The substitution process in [Rh-2(mu-S2CBn2)(CO)(4)] (7) by P(OMe)(3) has been studied by spectroscopic means and the full series of substituted complexes [Rh-2(mu-S2CBn2)(CO)(4-n){P(OR)(3)}] (n = 1, 4) has been identified in solution. The cis complex [Rh-2(mu-S2CBn2)(CO)(2)(mu-dppb)] (16) was obtained by reaction of 7 with the diphosphine dppb (1,4-bis(diphenylphosphino)butane). The molecular structures of the diolefinic dinuclear complexes [Rh-2(mu-S2CR2)(cod)(2)] (R = Bn (1), Pr-i (2); R-2 = -(CH2)(4)- (6)) and that of the cis complex 16 have been studied by X-ray diffraction.