Beaction of CH_2(Ph_2PSe)_2 (dppmSe_2) with (Ru_3(CO)_(12)). Fluxional behaviour of (Ru_3(#mu#_3-Se)_2(CO)_7(#mu#-dppm)) and crystal structures of (Ru_4(#mu#_4-Se)_2(#mu#-CO)(CO)_8(#mu#-dppm)) centre dot MeOH and (Ru_6(#mu#_3-Se)_4(CO)_(12)(#mu#-dppm

摘要

The reaction of [Ru_3(CO)(12)] with dppmSe_2 afforded the open-triangular nido cluster [Ru_3(#mu#_3-Se)_2(CO)_7(#mu#-dppm)] 1, the closo-octahedral species [Ru_4(#mu#_4-Se)_2(#mu#-CO)(CO)_8(#mu#-dppm)] 2 and the cubane-like cage [Ru_4(#mu#_3-Se)_4(CO)_(10)(#mu#-dppm)] 3. Multinuclear NMR data indicated a fluxional behaviour for 1 in solution consisting both in the reversible migration of a metal-metal bond in the cluster and in the oscillation of the methylene group of the dppm ligand. Pyrolysis of 1 gave the condensation derivative [Ru_6(#mu#_3-Se)_4(CO)_(12)(#mu#-dppm)_2] containing a central 64-electron butterfly core.