Transition-Metal-Substituted Dichlorobismuthanes as Starting Materials for Novel Bismuth−Transition-Metal Clusters^†

The reaction of [{Cp(CO)2Fe}BiCl2] (1a) with [Co(CO)4]- leads to the formation of the first heteroleptic substituted bismuthane, [(μ3-Bi){Co(CO)4}2{Fe(CO)2Cp}] (2). When the “open” complex 2 is irradiated, the heterocubane [Bi4{Co(CO)3}4] (3) is formed. [{Cp‘ ‘(CO)2Fe}BiCl2] (1b; Cp‘ ‘ = η5-C5H3-tBu2) reacts with [Fe(CO)4]2- to give the nido cluster [{Fe3(CO)9}{μ-BiFe(CO)2Cp‘ ‘}2] (4) and to give the complex [Bi4{μ3-Fe(CO)3}3{Fe(CO)2Cp‘ ‘}2] (5); the latter contains a distorted-tetrahedral Bi4 cluster core in which three of the faces are capped by Fe(CO)3 moieties. The reaction of 1b with Na2[W2(CO)10] yields the Bi-bridged tetrahedral W2Bi2 cluster [{W2(CO)8}(μ,η2-Bi2){μ-BiFe(CO)2Cp‘ ‘}] (6). In contrast to this, the molybdenum-substituted analogue [{Cp‘ ‘(CO)3Mo}BiCl2] (7) reacts with Na2[Fe(CO)4] to yield the arachno cluster [{Fe2(CO)6}{Fe(CO)4}{μ3-BiMo(CO)3Cp‘ ‘}2] (9). When 7 is reacted with Na2[W(CO)5], the complex [{Cp‘ ‘(CO)3Mo}2BiCl] (10) is obtained. The decomposition of compound 7 in THF leads to the ionic complex [(Cp‘ ‘MoCO)2(μ-Cl)3]2[Bi2Cl8(thf)2] (8). The crystal structures of all products are presented.