Synthesis of cis-C-Iodo-N-Tosyl-Aziridines using Diiodomethyllithium: Reaction Optimization, Product Scope and Stability, and a Protocol for Selection of Stationary Phase for Chro

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• 作者：Tom Boultwood ; Dominic P. Affron ; Aaron D. Trowbridge ; James A. Bull
• 刊名：The Journal of Organic Chemistry
• 出版年：2013
• 出版时间：July 5, 2013
• 年：2013
• 卷：78
• 期：13
• 页码：6632-6647
• 全文大小：618K
• 年卷期：v.78,no.13(July 5, 2013)
• ISSN：1520-6904

文摘

The preparation of C-iodo-N-Ts-aziridines with excellent cis-diastereoselectivity has been achieved in high yields by the addition of diiodomethyllithium to N-tosylimines and N-tosylimine鈥揌SO₂Tol adducts. This addition-cyclization protocol successfully provided a wide range of cis-iodoaziridines, including the first examples of alkyl-substituted iodoaziridines, with the reaction tolerating both aryl imines and alkyl imines. An ortho-chlorophenyl imine afforded a 尾-amino gem-diiodide under the optimized reaction conditions due to a postulated coordinated intermediate preventing cyclization. An effective protocol to assess the stability of the sensitive iodoaziridine functional group to chromatography was also developed. As a result of the judicious choice of stationary phase, the iodoaziridines could be purified by column chromatography; the use of deactivated basic alumina (activity IV) afforded high yield and purity. Rearrangements of electron-rich aryl-iodoaziridines have been promoted, selectively affording either novel 伪-iodo-N-Ts-imines or 伪-iodo-aldehydes in high yield.