PRODUCTION AND PURIFICATION OF PHOSPHINE OXIDE

摘要

PROBLEM TO BE SOLVED: To efficiently obtain a high purity phosphine oxide in a high yield which is useful e.g. for a catalyst for polymerizing alkylene oxide compounds by reacting a specific iminophosphorane with phosphorus oxychloride in an aprotic organic solvent having a dielectric constant equal to or above a specified value. SOLUTION: By reacting iminophosphoranes such as iminotris(dimethylamino) phosphorane expressed by formula I (wherein Rs are each a 1-10C hydrocarbon or two Rs on the same nitrogen atom may be combined with each other into a ring structure) with phosphorus oxychloride in an aprotic organic solvent such as toluene having a dielectric constant of >=2.2 at 20 deg.C, phosphine oxides of formula II are obtained. The aprotic organic solvent preferably is an organic solvent in which an aminophosphonium chloride of formula III is insoluble. Purification of the phosphine oxide preferably is carried out by washing a solution containing both the phosphine oxide and a water-immiscible organic solvent with water to form a phosphine oxide solution and by concentrating the solution to dryness.