CLUSTERS WITH FE6CD AND FE6HG STRUCTURAL UNITS

Various cadmium- and mercury-containing reagents were reacted with the anionic iron clusters Fe3(CO)112- (1) and Fe4(CO)132- (2) as their PPN salts. 1 and CdI2 yield the cluster (PPN)2[Fe6Cd(CO)22] (3), which is also obtained from 2 and CdI2 or 1 and ClCd[MoCP(CO)3]. The mercury-containing cluster (PPN)2[Fe6Hg(CO)22] (5), which is analogous to 3 is obtained from 1 or 2 with HgBr2. Upon varying the conditions PPN[Fe3(CO)11HgBr] (4) can be obtained from these reactions as well. The structure determination of 3 reveals the coordination of two Fe3 units to a central cadmium atom. which is surrounded by four iron atoms in a rather unsymmetrical coordination.