Asymmetric synthesis of phosphonotrifluoroalanine derivatives via proline-catalyzed direct enantioselective CC bond formation reactions of NH trifluoroacetimidoyl phosphonate

Based on enantioselective proline-catalyzed reactions between NH-iminotrifluoroethylphosphonate and acetone, an effective synthetic approach to both enantiomers of α-amino-α-trifluoromethyl-γ-oxobutylphosphonate was developed. The synthetic potential of these novel chiral synthons was illustrated by their cyclocondensation reactions with 4-chlorophenylisocyanate or 2,5-dimethoxytetrahydrofuran to afford the first representatives of phosphorylated 3,4-dihydropyrimidin-2-ones or 3H-pyrrolizines, incorporating pharmacophoric optically active fragments of phosphonotrifluoroalanine.