Synthesis of α,α-dialkyl-α-amino esters by α-alkylation of aldimines prepared from a novel pyridoxalmodelcompound was studied. The α-alkylation of the aldimines having an ethoxy-ethoxy group at C-3 proceeded most rapidly when LiOH was employed as a base and gave α,α-dialkyl-α-amino esters after acidic hydrolysis. The chelated structure composed of the aldimine and Li+ was also revealed by 1H-NMR analysis
stereoselective α-alkylation of N-terminal amino acid residue of peptides was achieved by Li+-mediated alkylation of aldimines prepared from the peptides and a pyridoxalmodelcompoundhaving a chiral ansa-structure and an ethoxyethoxy group at C-3. The stereochemistry and stereoselectivity of the reaction were found to be influenced predominantly by the chirality of the modelcompound and Li+, but little