Synthesis of α‐Ethynyl Glycines

Abstract

α‐Ethynyl glycine derivatives have a high potential for functionalization by derivatization of the amino acid or acetylene moiety, and, as a result, are important intermediates in the construction of biologically active compounds, including natural products. The main methods for the synthesis of ethynyl glycines and glycinols can be divided into six different transformations: (a) homologations of serinal derivatives, (b) nucleophilic alkynylations of α‐imino esters/alcohols or their precursors α‐halo glycinates, (c) derivatizations of alkynyl imino esters, (d) electrophilic alkynylations of α‐nitro esters and azlactones by using hypervalent iodine reagents, (e) intra‐ and intermolecular aminolysis reactions of epoxides, and (f) propargylic aminations through the cyclization of bis(imidate). This microreview summarizes the methods that were published from 1996 to 2015.