Triplet rearrangement of 1-biphenylyl-2,2-dimethylcyclopropane  

作　　者：WU,Guo-Sheng HU,Jun LI,Jiang-Pin Shanghai Institute of Organic Chemistry,The Chinese Academy of Sciences,Shanghai 200032 XU,Jian-Hua Department of Chemistry,Nanjing University,Nanjing 210008 

出　　处：《Chinese Journal of Chemistry》1992年第1期65-72,共0页中国化学（英文版）

基　　金：Work supported by fhe National Natural Science Foundation of China.

摘　　要：Direct and sensitized photolyses ot 1-biphenylyl-2,2-dimethylcyclopropane gave 2-methyl- 4-biphenylyl-1-butene as sole product.Comparison of the product formation quantum yields at zero conversion in direct and sensitized photolyses(1,7×10^(-3)vs.1.8×10^(-3))indicated that the rearrangement took place from the triplet excited state in both cases.A istepwise mechanism involving disrotatory ring opening of the cyclopropane and subsequent 1,3-H suprafacial shift is proposed and is consistent with the reaction multiplicity result,the orbital and state correlation diagram analyses as well as the prediction based on the Large K and Small K Concept.Direct and sensitized photolyses ot 1-biphenylyl-2,2-dimethylcyclopropane gave 2-methyl- 4-biphenylyl-1-butene as sole product.Comparison of the product formation quantum yields at zero conversion in direct and sensitized photolyses(1,7×10^(-3)vs.1.8×10^(-3))indicated that the rearrangement took place from the triplet excited state in both cases.A istepwise mechanism involving disrotatory ring opening of the cyclopropane and subsequent 1,3-H suprafacial shift is proposed and is consistent with the reaction multiplicity result,the orbital and state correlation diagram analyses as well as the prediction based on the Large K and Small K Concept.

关 键 词：Triplet rearrangement of 1-biphenylyl-2 2-dimethylcyclopropane 

分 类 号：O6[理学—化学]