Ti-mediated intramolecular cyclopropanation of N-alkenyl thioamides: scope and mechanistic study
摘要:
Although thioamides generally undergo a reductive alkylation process when they are treated with a Grignard reagent in the presence of Ti(OiPr)(4), substrates fitted with a but-3-enyl substitution at the nitrogen atom are shown to be converted into bicyclic aminocyclopropanes. These reactions are compared with the similar cyclisations of the corresponding carboxylic amide substrates. A mechanistic study is provided. Coincidently, new reagent systems are identified for the mediation of the same transformation. (C) 2014 Elsevier Ltd. All rights reserved.
Studies on the intramolecular Kulinkovich–de Meijere reaction of disubstituted alkenes bearing carboxylic amide groups
作者:Nouara Ouhamou、Yvan Six
DOI:10.1039/b306719j
日期:——
1,2-Disubstituted olefins bearing an acetamide group were found to undergo intramolecular Kulinkovichâde Meijere cyclopropanation in moderate yield but almost complete diastereoselectivity.
Ti-mediated intramolecular cyclopropanation of N-alkenyl thioamides: scope and mechanistic study
作者:Fabien Hermant、Emmanuel Nicolas、Yvan Six
DOI:10.1016/j.tet.2014.04.006
日期:2014.6
Although thioamides generally undergo a reductive alkylation process when they are treated with a Grignard reagent in the presence of Ti(OiPr)(4), substrates fitted with a but-3-enyl substitution at the nitrogen atom are shown to be converted into bicyclic aminocyclopropanes. These reactions are compared with the similar cyclisations of the corresponding carboxylic amide substrates. A mechanistic study is provided. Coincidently, new reagent systems are identified for the mediation of the same transformation. (C) 2014 Elsevier Ltd. All rights reserved.