Phosphoranaloge von Aminosäuren III1. Synthese optisch aktiver 1-Aminoalkylphosphonsäuren der (S)- und (R)-Reihe mit Hilfe von (-)-Ephedrin als Auxiliar

Abstract

Synthesis of Optically Active (S)- and (R)-1-Aminoalkylphosphonic Acids Using (-)-Ephedrine as Auxiliary The 2-benzoylaminomethyl-3,4-dimethyl-2-oxo-5-phenyl-2λ⁵-1, 3,2-oxazaphospholidines 2 and 2′, epimeric at the 2-position, are easily obtainable from benzoylaminomethylphosphonic acid dichloride (1) and (-)-ephedrine and are diastereoselectively alkylated at the P-C-N methylene group to yield compounds 3 and 3′, respectively. Hydrolysis of these products affords 1-aminoalkylphosphonic acids 4 and 4′, with (S)- and (R)-configuration, respectively.