A comparison of the reactions of PPh2CH2SR (R = Me, Ph) with alkyne-bridged dicobalt carbonyl complexes and with an iron dicobalt μ3-thioxo carbonyl complex
作者:Andrew J. Edwards、Stephen R. Mack、Martin J. Mays、Chi-Yu Mo、Paul R. Raithby、Moira-Ann Rennie
DOI:10.1016/s0022-328x(96)06234-1
日期:1996.7
The reactions of Ph(2)PCH(2)SR (R = Me, Ph) in toluene with the dicobalt complexes [Co-2(mu-R(1)CCR(2))(CO)(6)] (R(1) = R(2) = CO(2)Me and R(1) = H, R(2) = CO(2)Me) give the monosubstituted complexes [Co-2(mu-R(1)CCR(2))(CO)(5)PPh(2)CH(2)SMe] 1 and [CO2(mu-R(1)CCR(2))(CO)(5)PPh(2)CH(2)SPh] 2. On heating 1 and 2 in toluene solution, loss of CO leads to the bridged species [Co-2(mu-R(1)CCR(2))(mu-PPh(2)CH(2)SMe)(CO)(4)] 3 and [Co-2(mu-R(1)CCR(2))(mu-PPh(2)CH(2)SPh)(CO)(4)] 4. This transformation is readily reversed by treatment of 3 and 4 with CO, showing the Co-S bond in these complexes to be relatively weak. Similar reactions of Ph(2)PCH(2)SR (R = Me, Ph) with [Co2Fe(mu(3)-S)(CO)(9)], however, give only the ligand bridged species [Co2Fe(mu(3)-S)(mu-Ph(2)PCH(2)SR)(Co)(7)] (R = Me 5 and R = Ph 6). Treatment of 5 and 6 with CO causes cleavage of the Co-S bond but, in contrast to 3 and 4, the ligand bridged species readily reform when the CO purge ceases. The structures of 3a and 6 have been confirmed by single-crystal X-ray analysis.