Asymmetric addition of aldehydes and ketones to chiral 2-azapentadienyl lithium compounds: Diastereoselective synthesis of 4-vinyl-4,5-dihydro-oxazoles

被引：0

作者：

Vossmann, P. ^{[1
]}

Hornig, K. ^{[1
]}

Fröhlich, R. ^{[1
]}

Würthwein, E.-U. ^{[1
]}

机构：

[1] Institut für Organische Chemie, Westfälische Wilhelms-Universität Münster, Corrensstrasse 40, 48149 Münster, Germany

来源：

Synthesis | 2001年 / 09期

关键词：

Addition reactions - Aldehydes - Ketones - Nuclear magnetic resonance spectroscopy - Stereochemistry - X ray diffraction;

D O I：

10.1055/s-2001-15227

中图分类号：

学科分类号：

摘要：

Chiral 2-azapentadienyl lithium compounds 1, easily available by deprotonation of the corresponding N-allylimines 2, react with symmetrical and asymmetrical ketones and aldehydes to form new chiral, vinyl-substituted 4,5-dihydro-oxazoles 3. The structural properties of 1 in the gas phase and in solution were studied by quantum chemical calculations and NMR spectroscopy. The X-ray diffraction structure of 4,5-dihydro-oxazole 3d indicates the formation of a benzhydrol adduct. The new reactions are interpreted in terms of regioselective, stepwise additions of the carbonyl compounds to carbon atom C3 of 1 and subsequent removal of the chiral nucleofugal group.

引用

页码：1415 / 1426