Premium
NMR studies of chiral discrimination relevant to the enantioseparation of N ‐acylarylalkylamines by an ( R )‐phenylglycinol‐derived chiral selector
Author(s) -
Im Sung Hyun,
Ryoo Jae Jeong,
Lee KwangPill,
Choi SeongHo,
Jeong Young Han,
Jung Young Sik,
Hyun Myung Ho
Publication year - 2002
Publication title -
chirality
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.43
H-Index - 77
eISSN - 1520-636X
pISSN - 0899-0042
DOI - 10.1002/chir.10071
Subject(s) - chemistry , diastereomer , enantiomer , chiral derivatizing agent , chiral column chromatography , high performance liquid chromatography , chiral stationary phase , analyte , proton nmr , resolution (logic) , chiral auxiliary , chiral resolution , stereochemistry , chromatography , organic chemistry , enantioselective synthesis , catalysis , artificial intelligence , computer science
Recently, it was reported that the chiral recognition ability of ( R )‐ N ‐3,5‐dinitrobenzoyl phenylglycinol derivative was examined as a new HPLC chiral stationary phase (CSP 1 ) for the resolution of racemic N ‐acylnaphthylalkylamines. However, the mechanism of chiral discrimination on the CSP remained elusive until now. In this study, a spectroscopic investigation of the chiral discrimination mechanism of CSP 1 was undertaken using mixtures of ( R )‐ N ‐3,5‐dinitrobenzoyl phenylglycinol‐derived chiral selector ( 2 ) and each of the enantiomers of N ‐acylnaphthylalkylamines ( 3 ) by NMR study. First, the differences in free energy changes (ΔΔ G ) upon diastereomeric complexation in solution between the complex of each isomer with chiral selector 2 by NMR titration were calculated. The values were then compared with those estimated by chiral HPLC. The chemical shift changes of each proton on the chiral selector and analytes were also checked and it was found that the chemical shift changes decreased continuously as the acyl group on analytes increased in length. This observation was consistent with the HPLC data. From these experimental results, the interaction mechanism of chiral discrimination between the chiral selector and the analytes is more precisely explained. Chirality 14:329–333, 2002. © 2002 Wiley‐Liss, Inc.