Substituent effect on stereospecificity and energy of concert of the retro-Diels-Alder reaction of isopropylidenenorbornene

被引：15

作者：

Tian, J

Houk, KN ^{[1
]}

Klärner, FG

机构：

[1] Univ Calif Los Angeles, Dept Chem & Biochem, Los Angeles, CA 90095 USA

[2] Univ Essen Gesamthsch, Inst Organ Chem, D-45117 Essen, Germany

来源：

JOURNAL OF PHYSICAL CHEMISTRY A | 1998年 / 102卷 / 39期

关键词：

D O I：

10.1021/jp9823953

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

The synchronous concerted and stepwise diradical pathways of the retro-Diels-Alder reaction of isopropylidenenorbornene have been studied theoretically at the B3LYP/6-31G* level. The effect of the isopropylidene substituent on the competition between the two mechanisms was determined by comparing these results to those obtained earlier with norbornene. The ease of internal rotation of the methylene radical center relative to the C-C bond cleavage in the diradical intermediate is compared with experimental data on stereoselectivity in the retro-Diels - Alder reaction of stereospecifically dideuterated isopropylidenenorbornene. Experimental and theoretical evidence indicates that the lifetime of the diradical is long enough for the stereochemical scrambling in the thermal retro-Diels-Alder reaction.

引用

页码：7662 / 7667

页数：6

共 28 条

[1] STUDY OF SOME ORGANIC-REACTIONS USING DENSITY-FUNCTIONAL THEORY [J].