Synthesis of 4-, 5-, and 6-Boron Metallocarboranes from the Polyhedral C2B5H7 System

摘要

A series of more than 20 new cobalt(III)-small carborane sandwich complexes, of which six are described in this paper, has been prepared from closo-C2B5H7 via reduction with sodium naphthalide in THF, followed by reaction with CoCl2 and NaC5H5 and air oxidation. Separation on silica gel columns and TLC plates has given (pi-C2B4H6)Co(pi-C5H5), (pi-C2B5H7)Co(pi-C5H5), (pi-C2B6H8)Co(pi-C5H5), (pi-C2B4H6)Co2(pi-C5H5)2, (pi-C2B5H7)Co2(pi-C5H5)2 and (pi-C2B6H8)Co2(pi-C5H5)2, all of which are air-stable sublimable solids. The characterization is based on boron-11 and proton nmr, infrared, and mass spectra. (Author)