Conformational stability of atropisomeric 1-naphthylcarbinols and 1-(1-naphthyl)ethylamines

Serendipitous discovery of a pH-dependant atropisomer bond rotation: Toward a write-protectable chiral molecular switch?☆

“…Compound 1, (6-(3-chloro-4-fluoro-benzyl)-4-hydroxy-2-methyl-3,5-dioxo-2,3,5,6,7,8-hexahydro- [2,6]naphthyridine-1-carbo-ଝ This paper is part of the Special Issue 'Enantioseparations', dedicated to W. Lindner, edited by B. Chankvetadze and E. Francotte.…”

“…Restricted rotation about the carboxamide bond of 6-(3-chloro-4-fluoro-benzyl)-4-hydroxy-2-methyl-3,5-dioxo-2,3,5,6,7,8-hexahydro- [2,6]naphthyridine-1-carboxylic acid dimethylamide (compound 1) gives rise to two slowly interconverting enantiomers which can be resolved using chiral chromatography. xylic acid dimethylamide) is an investigational compound from these laboratories, the synthesis and pharmaceutical properties of which will be described in a forthcoming publication.…”

“…The chromatographic separation of slowly interconverting atropisomers is a popular subject within the field of chiral chromatography, with molecules from diverse structural classes having been studied using a variety of chromatographic techniques [1][2][3][4][5][6][7][8][9][10][11][12][13][14]. We herein report the serendipitous discovery of an unusual interconverting atropisomer system, 1, where a strong influence of pH on carboxamide bond rotation is observed.…”

Structure, Conformation, and Stereodynamics of the Atropisomers of Highly Hindered Benzyl Ethers

“…It has been reported that carbinols of the type Ar−C(OH)R 2 exhibit significant restricted rotation about the sp 2 −sp 3 bond, − which originates stereolabile atropisomers when the aryl moiety does not possess a local 2-fold symmetry axis. ,− , If the OH moiety is replaced by the bulkier −OMe group, the increased dimension is expected to affect significantly the conformational behavior, so that dynamic features, not observable in the corresponding carbinols, should be detectable. We thus investigated here the methylbenzyl ethers 1 − 5 , bearing substituents of different bulkiness (Chart ).…”

Stereochemistry and Recent Applications of Axially Chiral Organic Molecules

“…The rotational barriers about the single C sp 2 –C sp 3 bonds are generally very small and the conformational isomers (or atropisomers) due to the stereogenic axis cannot be isolated at room temperature. However, some cases are present in the literature . Berber and Clayden have recently shown the preparation of atropisomeric phenylcyclohexanes 22 , .…”