高等学校化学学报

高等学校化学学报 ›› 1991, Vol. 12 ›› Issue (5): 644.

• 论文 • 上一篇    下一篇

亚乙烯基卡宾H2CCC:的氢氢键插入和加成反应机理的研究

王秉泽, 王臣建, 邓从豪   

  1. 山东大学理论化学研究室, 250100
  • 收稿日期:1989-05-17 出版日期:1991-05-24 发布日期:1991-05-24
  • 通讯作者: 王秉泽
  • 基金资助:

    国家自然科学基金

Mechanisms of H-H Insertion and Addition of Cumulene Carbene H2CCC:

Wang Bing-ze, Wang Chen-Jian, Deng Cong-hao   

  1. Institute of Theoretical Chemistry, Shandong University, Jinan, 250100
  • Received:1989-05-17 Online:1991-05-24 Published:1991-05-24

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摘要： 用HF/3-21G解析梯度方法研究H2CCC:的氢氢键插入和加成反应机理,结果表明,H2CCC:的H-H插入为直接插入,取端端(end-on)接近方式;H2加成经两步完成.第一步是2+2加成,因对称性禁阻取三中心过渡态,四中心作用发生在反应的后期,第二步是CH3CHC:的1,2氢重排.预言气相中H-H插入容易发生,势垒值约为45kJ/mol.

关键词: H-H插入, 端端接近, 2+2加成, 三中心过渡态

Abstract: Reactions H2CCC: (1)+H2→CH2CCH2(2)+CH3CCH(3) are studied using HF/3-21Ggradient method. The insertion 1+H2→2 occurs easily in fashion of "end-on" approach with a barrier of about 45 kJ/mol. The addition 1+H2→3 is fulfilled in two steps, the 2+2 addition toethenylenene carbene, then followed by 1,2-hydrogen migration. Because of the symmetry prohibition, the 2+2 addition proceeds via a 3-center transition state with a high barrier, the 4-center interaction occurs in the later stage. The reactions 1+H2are kinetically controlled with 2 as the major product. The requirements for the carbene addition are discussed.

Key words: H-H Insertion, "End-on", approach, 2+2 addition, 3-Center transition state

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