The effects of conformation and solvation on optical rotation: Substituted epoxides

被引：31

作者：

Wilson, Shaun M. ^{[1
]}

Wiberg, Kenneth B. ^{[1
]}

Murphy, Michael J. ^{[1
]}

Vaccaro, Patrick H. ^{[1
]}

机构：

[1] Yale Univ, Dept Chem, New Haven, CT 06520 USA

来源：

CHIRALITY | 2008年 / 20卷 / 3-4期

基金：

美国国家科学基金会;

关键词：

intrinsic optical activity; conformational effects; solvation processes; nonresonant chiroptical response; density functional theory; vapor-phase optical activity; cavity ring-down polarimetry; polarizable continuum model;

D O I：

10.1002/chir.20448

中图分类号：

R914 [药物化学];

学科分类号：

100701 ;

摘要：

The vapor-phase optical rotation (or circular birefringence) of (S)-1,2-epoxybutane, (S)-epichlorohydrin, and (S)-epifluorohydrin has been measured at the nonresonant excitation wavelengths of 355 nm and 633 nm by means of Cavity Ring-Down Polarimetry (CRDP). Complementary solution-phase studies were performed in a,wide variety of dilute solvent media to highlight the pronounced influence of solute-solvent interactions. Density functional theory calculations of optical activity have been enlisted to unravel the structural and electronic provenance of experimental observations. Three stable, low-lying conformers have been identified and characterized for each of the targeted chiral species, with thermal (relative population weighted) averaging of their antagonistic chiroptical properties allowing specific rotation values to be predicted under both isolated and solvated conditions. For (S)-epichlorohydrin and (S)-epifluorohydrin, a self-consistent isodensity polarizable continuum model (SCI-PCM) has been exploited to gain further insight into the underlying nature of solvation effects.

引用

页码：357 / 369

页数：13

共 64 条

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