Palladium-Catalyzed Approach for the General Synthesis of (E)-2-Arylmethylidene-N-tosylindolines and (E)-2-Arylmethylidene-N-tosyl/nosyltetrahydroquinolines: Access to 2-Su

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• 作者：Chinmay Chowdhury ; Bimolendu Das ; Sanjukta Mukherjee ; Basudeb Achari
• 刊名：The Journal of Organic Chemistry
• 出版年：2012
• 出版时间：June 1, 2012
• 年：2012
• 卷：77
• 期：11
• 页码：5108-5119
• 全文大小：480K
• 年卷期：v.77,no.11(June 1, 2012)
• ISSN：1520-6904

文摘

A facile and efficient method for the synthesis of (E)-2-arylmethylidene-N-tosylindolines and (E)-2-arylmethylidene-N-tosyl/nosyltetrahydroquinoline variants has been developed through palladium-catalyzed cyclocondensation of aryl iodides with readily available 1-(2-tosylaminophenyl)prop-2-yn-1-ols and their higher homologues, respectively. The proposed reaction mechanism invokes the operation of trans-aminopalladation during cyclization (5/6-exo-dig), which ensures exclusive (E)-stereochemistry in the products. The method is fast, operationally simple, totally regio- and stereoselective, and versatile enough to access a variety of 2-substituted indoles and quinolines. The reactions proceeded efficiently with a wide variety of substrates and afforded the corresponding products in moderate to excellent yields.