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 sensit...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.展开更多
基金Work supported by fhe National Natural Science Foundation of China.
文摘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.
