Type II Intramolecular [5+2] Cycloaddition: Facile Synthesis of Highly Functionalized Bridged Ring Systems1. (10th December 2014)

• Record Type: Journal Article
• Authors: Mei, Guangjian; Liu, Xin; Qiao, Chuang; Chen, Wei; Li, Chuang‐chuang
• Is Part Of: Angewandte Chemie. Volume 127:Number 6(2015)
• Page Start: 1774
• Page End: 1778
• Publication Date: 2014-12-10
• Subjects: Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.201410806
• Languages: English
• ISSNs: 0044-8249

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>A type II intramolecular oxidopyrylium‐mediated [5+2] cycloaddition reaction allows the efficient and diastereoselective formation of various highly functionalized and synthetically challenging bridged seven‐membered ring systems (such as bicyclo[4.4.1]undecane, bicyclo[4.3.1]decane, bicyclo[5.4.1]dodecane, and bicyclo[6.4.1]]tridecane). This simple, thermal, direct transformation has a broad substrate scope and is high yielding, with high functional‐group tolerance and unique <italic>endo</italic> selectivity. The highly strained tricyclic cores of ingenol mebutate (picato) and cyclocitrinol are synthesized efficiently and diastereoselectively using this methodology.</p> </abstract>