Geometric Isomerism Based on Metal-Metal Bonds

摘要

The stereodynamics of metal-metal bonds has remained virtually unexplored until very recently. It is now known that the barriers for the degenerate reorientation of metal-metal bonds can be substantial. This opens the way for the preparation of clusters which differ on the basis of their metal-metal bonding networks. A test of this idea entails demonstration that clusters can exist as geometric isomers based exclusively on the relative positions of M-M bonds. This type of process assumes added significance to the extent that M-M bonding provides an electrochemically addressable means of controlling the structures of multimetallic frameworks. The reaction of (C_5Me_5)_2Ru_2S_4~3 with 2 equiv of (C_5H_5)Ru-(MeCN)_5~(+4) (MeCN solution, 25℃) proceeds according to eq 1. The red-brown salt [(C_5H_5)_2(C_5Me_5)_2Ru_4S_4](PF_6)_2 ([1]-(PF_6)_2) was obtained in high yield and good purity.