The reaction of [Os-3(mu-H)(CO)(10)(mu-CO)](-) with Ph2SbCl: a cluster with a six-membered Os4Sb2 ring and another with fluxional metal-metal bonds

摘要

Besides the cluster [Os-3(mu -H)(mu -SbPh2)(CO)(10)], 1, other products identified from the reaction of [Os-3(mu -H)(CO)(10)(mu -CO)](-) with Ph2SbCl in THF were [Os-3(mu -SbPh2)(2)(CO)(10)], 2a, and a dimeric form of 1, viz. [Os-3(mu -H)(mu -SbPh2)(CO)(10)](2), 3. Carrying out the reaction in CH2Cl2 gave 3 as the major product, while 2a has been demonstrated to result from the reaction of 1 with Ph2SbCl. In 2a the Os3Sb2 unit is almost planar; one of the Ph2Sb bridges is open while the other is closed. The two Ph2Sb-bridged Os-Os edges are shown by EXSY and variable-temperature H-1 NMR spectroscopy on the analogue [Os-3(CO)(10)(mu -SbPh2){mu -Sb(C6H4Me-p)(2)}], 2b, to interchange via an Os-Os bond fluxion. [References: 21]