nido-Pentaboranyl complexes of cadmium
Abstract
The complexes [Cd(µ-B5H8)Cl(PPh3)] and [Cd(µ-1-BrB5H7)Cl(PPh3)] have been prepared by reaction of [CdCl2(PPh3)2] with the potassium salts of the appropriate pentaborane anions. On the basis of boron-decoupled 1H, proton-decoupled, 11B and 31P n.m.r. spectra the complexes have been shown to be non-fluxional, η2 complexes of the ligands [B5H8]– and [1-BrB5H7]–. The cadmium is formally a 16-electron species and the structure resembles that recently established by X-ray analysis for the ‘isoelectronic’ copper complex [Cu(µ-B5H8)(PPh3)2]. Attempts to prepare analogous complexes of zinc and mercury have been unsuccessful.