通过在温和的条件下通过铜催化的磷化磷与烯基硼酸的氧化偶联反应,开发了一种可调谐策略,以高至极好的收率制备α,β-不饱和酯和α,β-不饱和γ-酮酯。不加水的反应得到α,β-不饱和酯,酮和酰胺,而α,β-不饱和γ-酮酯,1,4-α,β-不饱和二酮和α,β-不饱和γ-酮酰胺是使用5.0当量时获得。水。高2 O 18标记实验表明,水在α,β-不饱和γ-酮酸酯的形成中起着重要作用。在机理研究的基础上,提出了α,β-不饱和酯和α,β-不饱和γ-酮酯的合理形成机理。salts盐也可以代替磷化磷化物直接用作偶联伴侣。该反应表现出广泛的底物范围,良好的官能团耐受性,良好的区域选择性和多种偶联产物。
Facile and Environmentally Benign Zn-Mediated Cyclopropanation of Electron-Deficient 2-Iodoethyl-Substituted Olefins via Radical 3-<i>exo</i>-<i>trig</i>Manner
作者:Hideo Togo、Daisuke Sakuma
DOI:10.1055/s-2004-834828
日期:——
An efficient, simple, cheap, and environmentally benign preparation of cyclopropanes via 3-exo-trig manner from various electron-deficient 2-iodoethyl-substituted olefins with zinc powder in a mixture of t-butyl alcohol and water was achieved.
Facile preparation of cyclopropanes from 2-iodoethyl-substituted olefins and 1,3-dihalopropanes with zinc powder
作者:Daisuke Sakuma、Hideo Togo
DOI:10.1016/j.tet.2005.07.103
日期:2005.10
Two efficient, simple, cheap, and environmentally benign preparations of cyclopropanes were achieved. One is the formation via 3-exo-trig manner from various electron-deficient 2-iodoethyl-substituted olefins with zinc powder in a mixture of t-butyl alcohol and water, and the other is the formation via 3-exo-tet manner from various 1,3-dihalopropanes with zinc powder in ethanol.
The present invention relates to a novel process for the preparation of γ-amino acids, such as (±)-3-(aminomethyl)-5-methyl-hexanoic acid 1, which is a key intermediate in the preparation of the potent anticonvulsant pregabalin, (S)-(+)-3-(aminomethyl)-5-methyl-hexanoic acid 2.
[EN] T h e present invention relates to a novel process f o r the preparation of -amino 5 a c i d s, such as (±)-3-(aminomethyl)-5-methyl-hexanoic acid 1, which is a key intermediate in the preparation of the potent anticonvulsant pregabalin, (S)-(+)-3- ( a m i n o m e t h y l )- 5 -m e t h y l-h e x a n o i c acid 2 (1, 2). [FR] La présente invention concerne un nouveau procédé de préparation d'acides 5-amino, tels que l'acide (±)-3-(aminométhyl)-5-méthyl-hexanoïque 1, qui est un intermédiaire clé dans la préparation du puissant anticonvulsif prégabaline, acide (S)-(+)-3-(aminométhyl)-5-méthyl-hexanoïque 2 (1, 2).