Synthesis and X-Ray Molecular Structure Analysis of Tricobalt Clusters With Multi Ferrocenyl Groups

Abstract

The reaction of NaCo(CO)₄ with “impure FcPCl₂” in THF afforded two dark green products in low yield after column chromatography on silica-gel. Single crystal X-ray analysis showed that the products are Co₃(CO)₇(μ₃‒PFc)(μ₂‒PFc₂) (1) and Co₃(CO)₇(μ₃‒PFc)(μ₂‒P(H)Fc) (2). Both clusters have a tetrahedral skeleton composed of a capping μ₃‒PFc, a basal Co₃ triangle, and an edge (the Co‒Co bond) bridging μ₂-P(R)Fc group. Both clusters have 48 total skeletal electrons. The Co‒Co bond to which the μ₂‒P(R)Fc group bridges is significantly shorter than the other Co‒Co bonds, 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.

Key Words:

• Cobalt cluster
• multiferrocenyl groups
• X-ray structure
• total skeletal electron
• CV