The synthesis of amino acid derivatives by catalytic phase-transfer alkylations

Abstract

The current widespread interest in preparation and utilization of amino acids,2 the building blocks of life, is based on their use in many diversified areas. For example, amino acids are employed as protein dietary supplements,3 as drugs4 and as starting materials for synthesis of biologically active natural products.5 New and general synthetic routes to amino acids are, therefore, of interest for both large-scale production of known amino acids as well as preparation of rare and/or unknown amino acids. Phase-transfer reactions6 provide a potentially attractive synthetic route for preparation of higher amino acids from derivatives of simplest amino acid, glycine. We recently reported7 first general synthesis of amino acid derivatives using phase-transfer alkylations.B3g The Schiff base l7 is an active methylene compound in which both carboxylate and