Synthesis of α-Amino Esters via α-Nitro or α-Oxime Esters: A Review

Abstract

This review is an in-depth survey of the reported synthetic approaches for the preparation of racemic α-amino esters via the reduction of α-nitro or α-oxime ester intermediates. Accordingly, it describes the many pathways that have been designed to prepare such intermediates­. This includes synthesis starting with α-nitroacetates, dialkyl malonates, acetoacetates, diethyl oxalates as well as [2+3] or [2+4] cycloadditions using, respectively, alkyl carbonocyanidate N-oxides or alkyl 2-nitrosoacrylates. This review also contains the description of a myriad of side reactions which can occur when working with α-nitro esters­.1 Introduction2 α-Amino Esters from α-Nitroacetates via Condensation Reactions3 α-Amino Esters via C-Alkylation or C-Arylation of α-Nitroacetates4 α-Amino Esters from α-Nitroacetates Using Other Reactions5 Synthesis of α-Amino Esters via α-Oxime Esters6 Synthesis of α-Amino Esters via [2+3] Cycloadditions7 Synthesis of α-Amino Esters via [2+4] Cycloadditions8 On the Reduction of α-Oxime Esters9 Conclusion