A practical large scale chemical synthesis of chiral glycines

Abstract

(R)- and (S)-[2-2H]glycine of high chiral purity were synthesized in large quantities in [approximate] 40% overall yield from readily available starting materials via a totally chemical procedure. Reduction of either [1-2H]-furfural or [1-2H]-4-methoxybenzaldehyde with either (+) or (-)-B-isopinocampheyl-9-borabicyclo[3.3.1]nonane gave chiral arylmethyl alcohols which were converted into their respective phthaloyl amino derivatives of the opposite configuration at the methylene carbon via the Mitsunobu reaction. The aromatic groups were oxidatively unmasked to give their corresponding glycine derivatives by either ozone or ruthenium tetraoxide oxidation.