Pyrolytic and Photolytic Reactions. I. Thermal Rearrangement of 1-Acetyl- and 1-Isopropenyl-3-methylenecyclobutane
作者:Shigehiro Ooba、Masaki Ohta、Hiroshi Kato
DOI:10.1246/bcsj.43.1782
日期:1970.6
1-Acetyl- and 1-isopropenyl-3-methylenecyclobutane (I and II) were prepared and then subjected to pyrolysis. The pyrolysis of I at 304–340°C gave 2-methyl-5-methylene-Δ2-dihydropyrane, which was then converted to 4-methylenecyclohexanone at this temperature. The pyrolysis of II at 255–340°C gave 1-methyl-4-methylenecyclohexene, which was disproportionated at this temperature to p-xylene and 1,4-dimethylcyclohexene
制备 1-乙酰基-和 1-异丙烯基-3-亚甲基环丁烷 (I 和 II),然后进行热解。I 在 304-340°C 下热解得到 2-甲基-5-亚甲基-Δ2-二氢吡喃,然后在该温度下转化为 4-亚甲基环己酮。II 在 255-340°C 下热解得到 1-甲基-4-亚甲基环己烯,在该温度下歧化为对二甲苯和 1,4-二甲基环己烯。在这两种情况下都没有观察到裂解成烯烃。这些结果由两步双自由基机制解释。