高等学校化学学报 ›› 1991, Vol. 12 ›› Issue (3): 356.
• 论文 • 上一篇 下一篇
王秉泽, 邓从豪
收稿日期:
出版日期:
发布日期:
通讯作者:
基金资助:
国家自然科学基金
Wang Bing-ze, Deng Cong-hao
Received:
Online:
Published:
摘要: 用从头计算-解析梯度法研究了亚甲基环丙烷卡宾的重排反应。开环重排经Hückel型过渡态,在过渡态前后分别属2电子和4电子反应,取对旋和顺旋方式,遵从4n+2和4n规则。1,2氢重排经迁移氢进攻卡宾碳的空p轨道发生。用RHF/6-31-G**∥STO-3G方法算得开环势垒为24kJ/mol。1,2氢重排不是开环的竞争反应,其势垒为118kJ/mol。与环丙烷卡宾比较,亚甲基取代未改变其开环反应的类型与机理,但增大开环反应活性。
关键词: Hü, ckel型过渡态, 对旋, 顺旋
Abstract: Isomerizations of methylenecyclopropylidene were studied using ab initio gradient method. The ring opening occurs via a Huckel aromatic transition state. It is a 2 e reaction before the transition state and a 4 e one thereafter, obeying Huckel 4n+2 and 4n rules, respectively. The 1,2 Hmigration occurs by the attack of the carbene p orbital on the shift hydrogen. The ring opening barriers is 24 kJ/ mol, and the hydrogen shift barrier is 118 kJ/mol, at the RHF/6-31G**//STO-3G level. Relative to the ring opening of cyclopropylidene, the substitution results in a larger reactivity but does not change the type and the mechanism of the reaction.
Key words: Huckel type transition state, Disrotatory, Conrotatory
TrendMD:
王秉泽, 邓从豪. 亚甲基环丙烷卡宾的开环与1,2-氢迁移的从头算研究. 高等学校化学学报, 1991, 12(3): 356.
Wang Bing-ze, Deng Cong-hao . Ab initio Study of Ring Opening and 1,2-H Shift of Methylcnecyclopropylidenc. Chem. J. Chinese Universities, 1991, 12(3): 356.
0 / / 推荐
导出引用管理器 EndNote|Ris|BibTeX
链接本文: http://www.cjcu.jlu.edu.cn/CN/
http://www.cjcu.jlu.edu.cn/CN/Y1991/V12/I3/356