Synthesis of pyrido[b]cyclobuten-5-one and 1-azafulvenallene by flash vacuum pyrolysis of 3-chloroformyl-2-methylpyridine
作者:Chin-Hsing Chou、Cheng-Chang Wu、Wey-Kao Chen
DOI:10.1016/0040-4039(95)00940-e
日期:1995.7
The temperature and pressure dependence of products formed on pyrolysis of 3-chloroformyl-2-methylpyridine (6) have been studied. Pyrolysis of 6 at 575 °C and ca. 1×10−4 torr gives pyrido[b]cyclobuten-5-one (5) in 20% yield. Pyrolysis of 6 at 575 and 800 °C and under the pressure of ca. 1×10−2 torr give 1-azafulvenallene (7, 46%) and 1-cyanocyclopentadiene (8, 42%), respectively. Irradiation of 5 (λ