Dimethyl-, dichloro- and chloromethylphenylcarbamates of amylose as chiral stationary phases for high-performance liquid chromatography

Abstract

Twelve dimethyl-, dichloro- and chloromethylphenylcarbamate derivatives of amylose were prepared and their chiral recognition abilities were evaluated as chiral stationary phases for high-performance liquid chromatography. ortho-Substituted phenylcarbamate derivatives of amylose showed high chiral recognition abilities, although cellulose phenylcarbamate derivatives with ortho substituents on the phenyl moiety showed low chiral recognition. The superiority of 5-chloro-2-methylphenylcarbamate over the corresponding dimethyl- and dichlorophenylcarbamate derivatives of amylose was demonstrated. The roles of the NH residue of the carbamate moieties and methyl and chloro groups in chiral recognition were elucidated using IR and 1H NMR spectroscopic data. The tris(5-chloro-2-methylphenylcarbamate) of amylose exhibited the highest chiral recognition ability among the amylose derivatives synthesized, and can be used for the separation of some chiral drug enantiomers.