Diels−Alder Cycloaddition and Ring-Closing Metathesis: A Versatile, Stereoselective, and General Route to Embellished Bridged Bicyclic Systems, Carbocyclic Framework of Secoatisanes, and Homolog

详细信息    查看全文

• 作者：Vishwakarma Singh ; Pramod K. Sahu ; Bharat C. Sahu ; Shaikh M. Mobin
• 刊名：Journal of Organic Chemistry
• 出版年：2009
• 出版时间：August 21, 2009
• 年：2009
• 卷：74
• 期：16
• 页码：6092-6104
• 全文大小：1143K
• 年卷期：v.74,no.16(August 21, 2009)
• ISSN：1520-6904

文摘

A general and stereoselective methodology for the synthesis of bridged bicyclic octenones having various types of alkenyl chains and a tricyclic framework of secoatisanes and higher analogues is reported. In situ generation and cycloaddition of 2-allyl-6,6-spiroepoxycyclohexadienones with ethyl acrylate gave bicyclo[2.2.2]octanes having an allyl group at the bridgehead and other chemically distinguishable functionality in a regio- and stereoselective fashion. Selective manipulation of adducts led to the introduction of other olefinic chain of variable lengths at the carbon adjacent to the bridge head. Ring-closing metathesis in bicyclooctanes having olefin tethers provided an efficient route to tricyclic systems having bicyclo[2.2.2]octane framework having spiro-fused six-, seven-, and eight-membered rings.