To date the greenest method for the preparation of α-hydroxyphosphonates from substituted benzaldehydes and dialkyl phosphites

Abstract

Recent synthetic methods for α-hydroxyphosphonates comprise a green, solvent-free accomplishment of the Pudovik reaction that was typically followed by extractions and recrystallization, or even by chromatography, or other operations. We now developed a general procedure applying 10% of triethylamine as the catalyst and a minimum quantity of acetone as the solvent, giving the products in a pure form after a reflux of 5-120 min following the addition of some n-pentane and crystallization on cooling.