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Updated: Nov 20, 2025

Preparation of Enantiopure Non-Activated Aziridines and Synthesis of Biemamide B, D, and epiallo-Isomuscarine
Published on: June 13, 2022
Achiral Molecular Recognition of Substituted Aniline Position Isomers by Crown Ether Type Chiral Stationary Phase
Atsushi Ohnishi1,2, Tohru Shibata3, Tatsuya Imase4
1R&D Center, Analytical Tools BU, CPI Company, Daicel Corporation, Myoko, Niigata 944-8550, Japan.
Abstract:
To understand the selectivity of the crown ether type chiral stationary phase (CSP), the retention selectivity for aniline and the positional isomers of substituted anilines were studied. In various substituted isomers, except nitroaniline, a remarkable decrease of retention due to steric hindrance was observed for the 2-substituted isomer. To determine the detailed molecular recognition mechanism, quantum chemical calculations were performed for the aggregates between the crown ether and the anilines. The results suggested that the 20-Crown-6, which includes a phenyl-substituted 1,1'-binaphthyl moiety, interacts with alkyl and aryl amines in an unconventional form different from the proposed one for 18-Crown-6.
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