Studies on the Reaction of Aziridines with Nitriles and Carbonyls: Synthesis of Imidazolines and Oxazolidines

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• 作者：Shikha Gandhi ; Alakesh Bisai ; B. A. Bhanu Prasad ; Vinod K. Singh
• 刊名：Journal of Organic Chemistry
• 出版年：2007
• 出版时间：March 16, 2007
• 年：2007
• 卷：72
• 期：6
• 页码：2133 - 2142
• 全文大小：187K
• 年卷期：v.72,no.6(March 16, 2007)
• ISSN：1520-6904

文摘

Reaction of N-tosylaziridines with nitriles and carbonyls to produce imidazolines and oxazolidines hasbeen studied in the presence of a variety of Lewis acids. The reaction is efficient with 1 equiv of BF₃·Et₂Oor Et₃OBF₄ in CH₂Cl₂. However, it is catalytic with metal triflates that give the best results for cycloadditionof N-tosylaziridine with nitriles under solvent free conditions. The same reaction with carbonyls proceedsbest in CH₂Cl₂ in the presence of molecular sieves. Among various triflates, Zn(OTf)₂ has been found tobe the best. The cleavage of the N-Ts bond of the cyclized products has been studied in order to makeit more versatile in synthesis. The mechanistic aspect of the reaction has been studied by using chiralaziridines as substrates. These formal [3 + 2] cycloaddition reactions of aziridines with nitriles andcarbonyls proceed in a Ritter fashion.