Synthesis of chiral cyclic nitrones via a nitrosoketene intermediate and their use for the complete EPC synthesis of nonproteinogenic amino acids

Abstract

New cyclic chiral nitrones constituting two diastereomers were synthesized by the reaction of isonitroso Meldrum's acid with l-menthone via a nitrosoketene intermediate. Both nitrones reacted with allyltrimethylsilane diastereoselectively to give the corresponding isoxazolidine derivatives as sole products, which converted to ( S)- and ( R)-allylglycines in ca. 100% ee, respectively.