Activation parameters for 1,5-hydrogen transfer and intramolecular cycloaddition in a thermally generated cyclopentane-1,3-diyl
作者:Thomas H. Peterson、Barry K. Carpenter
DOI:10.1021/ja00066a016
日期:1993.6
of the corresponding bicyclo[2.1.0]pentane derivatives. Three reactions of the biradical (besides ring closure) are detected. One is ring opening to 3-methyl-3-(3-phenylpropyl)-1,4-pentadiene. A second is intramolecular transfer of a benzylic hydrogen to the cyclopentane-1,3-diyl. An activation enthalpy of 8 kcal/mol is estimated for this 1,5-hydrogen transfer. The third reaction is intramolecular cycloaddition
双基 2-甲基-2-(3-苯基丙基)环戊烷-1,3-二基可逆地通过相应双环[2.1.0]戊烷衍生物的立体异构混合物的气相热解产生。检测到双自由基的三个反应(除了闭环)。一种是对 3-甲基-3-(3-苯基丙基)-1,4-戊二烯开环。第二种是将苄基氢分子内转移到环戊烷-1,3-二基。估计此 1,5-氢转移的活化焓为 8 kcal/mol。第三个反应是 1,3-二基与苯环的分子内环加成反应。估计该环加成反应的活化焓为 7 kcal/mol