Separate Deprotonation Reactions Converge Mechanistically for a New Cyclization of Benzyl 1-Alkynyl Sulfones
作者:M. Selim Hossain、Adrian L. Schwan
DOI:10.1021/ol202196y
日期:2011.10.7
A heretofore unknown LDA-induced conversion of benzyl 1-alkynyl sulfones to 1H-2-benzothiopyran-S,S-dioxides is demonstrated. A benzyl carbanion, accessible by two means, is thought to cyclize by temporary disruption of aromaticity. Key intermediates are observed by ReactIR analysis. Thiophene derivatives are also amenable to cyclization, forming 7H-thieno[2,3-c]thiopyran-S,S-dioxides.
证明了迄今为止未知的LDA诱导的苄基1-炔基砜向1 H -2-苯并噻喃-S,S-二氧化物的转化。苄基碳负离子可通过两种方式进入,被认为是由于芳香族的暂时破坏而环化的。通过ReactIR分析观察到了关键中间体。噻吩衍生物也适合环化,形成7 H-噻吩并[2,3- c ] thiopyran- S,S-二氧化物。