The present invention relates to a novel method for producing cyclopentenolone of the formula (I), ##STR1## which is a useful intermediate for producing agricultural chemicals, which comprises reacting an acetonedicarboxylic ester of the formula (VII), ##STR2## wherein R is a C.sub.1 -C.sub.6 alkyl group, with 2-propynyl chloride in the presence of magnesium alkoxide and in the presence of alkali iodide to obtain novel mono-(2-propynyl)-substituted acetonedicarboxylic ester of the formula (VI), ##STR3## wherein R is as defined above; hydrolyzing the mono-(2-propynyl)-substituted acetonedicarboxylic ester of the formula (VI) under alkaline conditions with an alkali and then reacting the hydrolyzed product with methylglyoxal of the formula, ##STR4## to obtain novel .gamma.-diketone of the formula (V), ##STR5## and ring-closing the .gamma.-diketone of the formula (V) under alkaline condition.
本发明涉及一种生产
环戊烯酮的新方法,其
化学式为(I),##STR1##
环戊烯酮是生产农业
化学品的有用中间体,该方法包括在
镁烷氧和
碘化物存在下,将
化学式(VII)的
丙酮二
羧酸酯,其中R是C.sub.1-C.sub.6烷基,与2-
丙炔基
氯反应,以获得
化学式(VI)的新型单-(2-
丙炔基)-取代的
丙酮二
羧酸酯,其中R如上所述;在碱性条件下,用碱
水解单-(2-
丙炔基)-取代的
丙酮二
羧酸酯,然后将
水解产物与
化学式的甲基
乙酰乙酸醛反应,以获得
化学式(V)的新型.gamma.-二酮,##STR5## 并在碱性条件下使.gamma.-二酮环闭合。