Verfahren zur Herstellung von Dialkylphosphiten aus Alkoholen und phosphoriger Saeure

摘要

Improved process for the preparation of dialkyl phosphites by means of refluxing phosphorous acid with alcohols under azeotropic separation of the reaction water formed, wherein primary or secondary straight-chained or branched aliphatic alcohols having at least 4 carbon atoms are reacted in an excess of at least 45 percent over the stoichiometrical amount with phosphorous acid in the absence of an inert solvent until the amount of acid in the reaction mixture is as low as possible. In comparison to known processes the dialkyl phosphites are obtained according to the instant process in higher yields and with higher purity. The dialkyl phosphites are valuable intermediates. Owing to their high purity, they are especially suitable as starting materials for such reactions catalyzed by radicals.