作者:James S. Chickos、H. Monty Frey
DOI:10.1039/p29870000365
日期:——
and 38.38 ± 1.7 (10.785 ± 0.7), respectively. The regiochemistry observed in fragmentation and in the 1,3-sigmatropic rearrangement of the starting material is discussed in terms of substituent effects found in other cyclobutane and vinylcyclobutane thermolyses. The fragmentation process and the isomerization to 4,4-dimethylcyclohexene and 2-methylhepta-1,6-diene is believed to proceed through the intervention
已经研究了2,2-二甲基-1-乙烯基环丁烷的热分解动力学随温度从263至301℃的变化。反应中产生的初级产物包括异丁烯和丁二烯,4,4-二甲基环己烯,2-甲基庚-1,6-二烯和顺-2-甲基庚-1,5-二烯。反式-2-甲基庚-1,5-二烯和2,4-二甲基六-1,5-二烯是通过3,3-σ重排由顺-2-甲基庚-1,5-二烯制得的。该反应服从一级动力学,并且不受表面影响。活化能(kcal mol –1)和(log A / s –1)的总分解和初级产物的形成为45.73±0.3(14.427±0.12),47.71±0.7(15.087±0.3),44.35±1.6(12.53±0.6),45.0±1.3(12.24±0.5)和38.38±1.7(10.785±0.7)。根据在其他环丁烷和乙烯基环丁烷热解中发现的取代基效应,讨论了在原料的断裂和1,3-σ重排中观察到的区域化学。据信通过6-甲基庚-1-烯-3