Improved Chiral Derivatizing Agents for the Chromatographic Resolution of Racemic Primary Amines

Article abstract of DOI:10.1021/jo00163a019

Several 4- and/or 5-aryl-substituted 2-oxazolidones have been prepared and studied as chiral derivatizing agents (CDA) for the chromatographic resolution of chiral primary amines via diastereomeric allophanates.The diastereomeric allophanates derived from either racemic primary amines and cis-4,5-diphenyl-2-oxazolidone-3-carbamyl chloride or racemic isocyanates and cis-4,5-diphenyl-2-oxazolidone show sufficient NMR chemical shift differences and chromatographic separability that this heterocyclic system should prove to be a very useful CDA for the chromatographic resolution and determination of the absolute configuration of a variety of chiral primary amines.The diastereomeric allophanates are readily hydrolyzed to return both chiral components of the allophanates in excellent yield.Both solution and adsorbed conformations of these allophanates are discussed in reference to the determination of the absolute configuration of the allophanates (and hence of the chiral primary amine) from the senses of NMR nonequivalence between and chromatographic elution order of the diastereomers.