Synthesis and 31P NMR study of chromium, molybdenum, and palladium complexes with 9-substituted 1,2-bis(diphenylphosphanyl)-o-carboranes

Abstract

9-Substituted 1,2-bis(diphenylphosphanyl)-o-carboranes were synthesized from the corresponding 9-R-o-carboranes (R = I, i-Pr, SMe), and their complexes with chromium, molybdenum, and palladium were obtained. The coordination chemical shifts calculated from the ³¹P NMR spectra of the complexes and free ligands showed that the substituent at B⁹ of carborane affects the strength of the ligand-to-metal binding, but the latter is determined to a greater extent by the nature of the metal and its ligand environment.