Application of Axially Dissymmetric 1,1′-Binaphthyl Derivatives to Chiral Derivatizing Agents

Axially dissymmetric 2′-methyl- and 2′-methoxy-1,1′-binaphthyl-2-carboxylic acid (1,2) were effectively utilized as chiral derivatizing agents for discrimination of enantiomeric alcohols and amines by high performance liquid chromatography (HPLC) on silica gel. Especially, 2 had excellent chirality-recognizing ability, and could also be utilized for discrimination by ¹H NMR with the aid of Eu(fod)₃. The elution behavior of a pair of diastereomeric esters or amides on HPLC, as well as the NMR behavior of the diastereomers were rationally explained based on X-ray crystallography analyses. Carbonyl cyanide derivatives of 1 and 2 were successfully applicable to resolution of β-adrenergic blocker enantiomers in biological fluids by HPLC. These diastereomeric esters were highly responsive to a fluorescence detector, the limit of detection being 200 pg and 30 pg (at a signal-to-noise ratio of 5), respectively. Also reported are convenient methods for the preparation of these reagents.