CHEMISTRY OF THE PARAMAGNETIC CO-3(CO)(9)(MU(3)-S) CLUSTER - RATIONALSYNTHESIS OF CO-3(CO)(7)(MU-X)(MU(3)-S) COMPLEXES

The paramagnetic Co-3(CO)(9)(mu(3)-S) cluster (1) reacts with organic compounds containing S-H, S-S, or P-H bonds to give diamagnetic Co-3(C O)(7)(mu-X)(mu(3)-S) (mu-X = (mu-L, mu-(1,2-eta)-L, and mu-(1,3-eta)-L ) complexes. The reaction was used to prepare the derivatives with mu- L = SR (2a-h; R = Et, t-Bu, CH2Ph, allyl, Ph, C6F5, 2-naphthylt CH2CH2 OH) and PPh2 (7), mu-(1,2-eta)-L = P(S)Ph-2 (8), and mu-(1,3-eta)-L = S2CR (R = SMe (4), OMe (5), Ph (6)). The reaction results in an increa se of the oxidation state of cobalt and may be therefore called an oxi dative substitution. It is the first successful and rational way to pr epare derivatives of Co-3(CO)(9)(mu(3)-S), a fundamental cluster molec ule described in 1961. The crystal structures of the triphenylphosphin e-substituted derivative of 2b, Co-3(CO)(4)( PPh3)(3)(mu-S-t-Bu)(mu(3) -S) (3), and of 4, 6, and 8 were determined. A new, high-yield synthes is of 1 is described.