The regioselective α-alkylation of the benzophenone imine of glycinamide, alaninamide, and related derivatives

Abstract
The benzophenone imine of glycinamide was alkylated using ion pair extraction (RX, 10% aq. NaOH, Bu4NHSO4 (1 equiv.), CH2Cl2, rt) to give the α-monosubstituted products, which were then alkylated a second time using stronger basic conditions (KO-t-Bu, THF, 0 °C, RX). Crystal structures of the Schiff bases of glycinamide, an α-monosubstituted and an α,α-disubstituted product were reported.Key words: benzophenone imines, Schiff bases, alkylation, ion pair extraction (IPE), phase-transfer catalysis (PTC), anhydrous base, X-ray crystal structures.