THE CONFORMATIONAL ANALYSIS AND REACTION MECHANISM FOR HOFMANN ELIMINATION OF QUATERNARY AMMONIUM HYDROXIDES

被引：1

作者：

Xu Xiaojie ^{[1
]}

Yao Zhengui ^{[1
]}

Ye Xiulin ^{[1
]}

Tang Youqi ^{[1
]}

Fu Heng ^{[2
]}

Qian Minxie ^{[2
]}

机构：

[1] Peking Univ, Dept Chem, Beijing, Peoples R China

[2] Acad Sinica, Inst Chem, Taipei, Taiwan

来源：

ACTA PHYSICO-CHIMICA SINICA | 1989年 / 5卷 / 04期

关键词：

D O I：

10.3866/PKU.WHXB19890405

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：

It is known that there are many examples of the thermal elimination of quaternary ammonium hydroxides which do not follow the Hofmann rule. Ye Xiulin et al. proposed the "conformational rule" for the elimination of quaternary ammonium hydroxides, and then, eight quaternary ammonium hydroxides were synthesised and subjected to the elimination. The results show that the conformational rule is superior and acceptable. DPCILO AND CNDO/2 methods were used to calculate the conformational energy of some quaternary ammonium cations with different conformations and the distribution of charge for studying the mechanism of Hofmann elimination reaction. The results show that the conformational rule, based on the conformational energy, can be used to explain the Hofmann elimination reaction well, but the elimination of straight chain alkyl groups other than the ethylic groups should follow cis-E2 elimination mechanism instead of trans-E2 one proposed by Ye Xiulin.

引用

页码：398 / 402

页数：5

共 4 条

[1] AMINE OXIDES .3. SELECTIVE FORMATION OF OLEFINS FROM UNSYMMETRICAL AMINE OXIDES AND QUATERNARY AMMONIUM HYDROXIDES [J].