Structure and reactivity of transition metal substituted dichloroantimony and dichlorobismuth complexes

Abstract

The dichloro Group 15 complexes [BiCl2] (Cpx = Cp, 5-C5H3tBu2) 1a, b and [SbCl2] 3 are prepared. The crystal structure determination of 1b and 3 shows a polymeric chlorine bridged structure for the bismuth complex 1b whereas for the antimony compound 3 a molecular structure with weak intermolecular chlorine bridges is found. The reaction of 1a or 3 with magnesium leads to the threefold transition-metal substituted complexes [(µ3-E)3] ( 5: E = Bi, Cpx = Cp; 7: E = Sb, Cpx = Cp), whereas the analogous reaction of 1b results in the disubstituted bismuth chloro complex [2BiCl] 6. Finally, the reaction of an equimolar mixture of 1a and 3 with magnesium yields the novel antimony-bridged compound [(µ3-Sb)] 8.