Redox deracemization of phosphonate-substituted dihydropyrimidines

An efficient redox deracemization of the phosphonic ester substituted 3,4-dihydropyrimidin-2-one (DHPM) derivatives is described. The one-pot deracemization strategy consisted of the oxidization to destroy the stereocenter center and the following asymmetric transfer hydrogenation to regenerate the chiral carbon center with the vicinal phosphonic ester group, providing a series of optically active phosphonate substituted DHPMs with up to 96% ee.