Synthesis and X-ray molecular structure analysis of tricobalt clusters with multi ferrocenyl groups

The reaction of NaCo(CO)(4) with "impure FcPCl(2)" in THF afforded two dark green products in low yield after column chromatography on silica-gel. Sin gle crystal X-ray analysis showed that the products are Co-3(CO)(7)(mu(3)-P Fc)(mu(2)-PFc(2)) (1) and Co-3(CO)(7)(mu(3)-PFc)(mu(2)-P(H)Fc) (2). Both cl usters have a tetrahedral skeleton composed of a capping mu(3)-PFc, a basal Co3 triangle, and an edge (the Co-Co bond) bridging mu(2)-P(R)Fc group. Bo th clusters have 48 total skeletal electrons. The Co-Co bond to which the m u(2)-P(R)Fc group bridges is significantly shorter than the other Co-Co bon ds, but these are in the range of single Co-Co bonds. CV measurements have shown that two reduction peaks are observed for 1 while a single reduction peak is observed for 2.