A Mechanistic Study on the Nucleophilic Addition Reactions of Benzylamines to the Activated Olefins

Bulletin of the Korean chemical society

Hyuck Keun Oh¹ 

关键词: Nucleophilic addition reaction;    Single-step process;    Cross-interaction constant;    Kinetic isotope effects;    Four-center cyclic transition state;   

DOI  :  

学科分类：化学（综合）

来源: Korean Chemical Society

【 摘 要 】

Kinetic studies of the additions of benzylamines to a noncyclic dicarbonyl group activated olefin, methyl �?- acetyl-�? -phenylacrylates (MAP), in acetonitrile at 30.0 oC are reported. The rates are lower than those for the cyclic dicarbonyl group activated olefins. The addition occurs in a single step with concurrent formation of the C_�?-N and C_�?-H bonds through a four-center hydrogen bonded transition state. The kinetic isotope effects (k_H/k_D > 1.0) measured with deuterated benzylamines (XC₆H₄CH₂ND₂) increase with a stronger electron acceptor substituent (ヤヲ X > 0) which is the same trend as those found for other dicarbonyl group activated series (1-4). The sign and magnitude of the cross-interaction constant, �?_XY, is comparable to those for the normal bond formation processes in the S_N2 and addition reactions. The relatively low ツH× and large negative ツS× values are also consistent with the mechanism proposed.

【 授权许可】

Unknown