A novel synthesis of tricyclo[5.1.0.0 3,5 ]octane-2,6-dione derivatives via double Michael addition-induced cyclopropanation reactions
作者:Sadao Tsuboi、Xuan Ye、Katsushi Kunito、Takashige Ono
DOI:10.1016/s0040-4020(01)00180-6
日期:2001.4
Tricyclo[5.1.0.03,5]octane-2,6-diones 1a–q were prepared in moderate yields by the reaction of α,β-unsaturated esters 2 with dihalomethane in the presence of butyllithium, and by the reaction of dichloromethyl α,β-unsaturated ketones 3 with sodium ethoxide, respectively. This reaction was newly explained by a mechanism involving intermolecular double Michael additions of enolate anion 4 of ketones
在α-β-不饱和酯2与二卤代甲烷在丁基锂存在下反应,以及二氯甲基α反应以中等收率制得三环[5.1.0.0 3,5 ]辛烷-2,6-二酮1a – q,β-不饱和酮3分别与乙醇钠。该反应是通过涉及酮3的烯醇酸根阴离子4的分子间双迈克尔加成以及随后的环丙烷化的机理来新解释的。