Revising the [PdCl2(1,2-(PPh2)2-1,2-C2B10H10)] synthesis and comparison of its behavior with [PdCl2(1,2-(PiPr2)2-1,2-C2B10H10)]. Crystal structure of [PdCl2(1,2-(PPh2)2-1,2-C2B10H10)]

Two methods for the revised synthesis of [PdCl2(1,2-(PPh2)2-1,2-C2B10H10)] are described. They differ on the reagent complex, to say 1,2-bis(diphenylphosphino)-1,2-dicarba-closo-dodecaborane was mixed with [PdCl2(cod)] or [PdCl2(PhCN)] in non-nucleophilic solvents. The structure of [PdCl2(1,2-(PPh2)2-1,2-C2B10H10)] was determined by single-crystal X-ray study. The carborane cage is coordinated bidentately through the P atoms to the Pd(II) ion, the remaining two positions are occupied by two chloride ions which are mutually cis. Overall, the coordination about the metal can be described as a slightly distorted square-planar. The reaction of 1,2-bis(diisopropylphosphino)-1,2-dicarba-closo-dodecaborane in dichloromethane produced mostly a compound with similar formula, however some deboronation took place and [Pd2(μ-Cl)2{7,8-(PiPr2)2-7,8-C2B9H10}2] was also produced. Larger amounts of this dinuclear complex were obtained when the closo species was refluxed for few minutes in a mild nucleophilic solvent.