Abstract A convenient protocol for the smooth conversion of the resistant P [BOND] O bond in phosphane oxides into a reactive P [BOND] N bond of synthetically useful pyrazolylphosphonium salts is described. A highly charged, oxophilic, phosphorus-centered trication is employed and the reactions are conducted at room temperature with quantitative yields. The resulting pyrazolylphosphonium cations are valuable synthetic intermediates ...
