A CONVENIENT PREPARATION OF 2-SUBSTITUTED 2-CYCLOPENTENONES FROM CYCLOPENTANONE USING 2-(MORPHOLINOTHIO)BENZOTHIAZOLE
作者:Sigeru Torii、Hideo Tanaka、Toshihiro Kudai、Sinichi Watanabe
DOI:10.1246/cl.1979.147
日期:1979.2.5
2-Substituted 2-cyclopentenones (4), a precursor of jasmonoids, were prepared in 47–77% overall yields from cyclopentanone (1) via 2-(2-benzothiazolylthio)cyclopentanone (2). Treatment of 1 with 2-(morpholinothio) benzothiazole gave 2 in 98% yield. Alkylation of 2 with RBr–K2CO3–KI–acetone followed by removal of the 2-mercaptobenzothiazole by thermolysis in benzene containing p-TsOH at 140 °C afforded
2-取代的 2-环戊烯酮 (4) 是茉莉酮类化合物的前体,通过 2-(2-苯并噻唑硫基) 环戊酮 (2) 从环戊酮 (1) 以 47-77% 的总产率制备。用2-(吗啉代)苯并噻唑处理1得到98%产率的2。2 用 RBr-K2CO3-KI-丙酮烷基化,然后通过在含有 p-TsOH 的苯中在 140°C 下热解去除 2-巯基苯并噻唑,得到 (4)。