Pentacoordinate silicon(iv): cationic, anionic and neutral complexes derived from the reaction of NHC→SiCl4 with highly Lewis acidic (C2F5)2SiH2

Abstract

Addition of NHC→SiCl₄ to the highly Lewis acidic bis(pentafluoroethyl)silane ((C₂F₅)₂SiH₂) afforded the salt [(NHC)₂SiCl₂H][(C₂F₅)₂SiCl₃] with pentacoordinate silicon in the cation and the anion. The anion represents the first example of a chlorosilicate structurally characterized in the solid state. In this reaction, the long sought pentacoordinate NHC-adduct of silicochloroform was identified as an intermediate and its crystal structure is presented.