反应详情

温度

230 °C

A crude cyclododecanone was produced as described in Japanese laid-open patent publication No. 2000-256340, No. 2000-026441, No. 2001-302650 and No. 2001-226311. Specifically, 1,5,9-cyclododecatriene was blended with hydrogen peroxide water, and phosphotungstic acid and trioctylmethylammonium chloride as catalysts were added to initiate oxidation, giving 1,2-epoxy-5,9-cyclododecadiene. After recovering unreacted 1,5,9-cyclododecatriene by distillation, 1,2-epoxy-5,9-cyclododecadiene was purified by distillation. 1,2-Epoxy-5,9-cyclododecadiene thus obtained was hydrogenated over platinum/carbon as a catalyst, to hydrogenate a double bond. To the epoxycyclododecane thus obtained was added lithium iodide as a catalyst, and the mixture was heated to 230° C. for isomerization to give cyclododecanone. Purification of cyclododecanone and production of laurolactam were conducted as described in Example D1, and impurities were analyzed. In cyclododecanone after purification, the impurities at 24.68 min, 24.73 min and 24.87 min were contained in 2.4 ppm by weight, 2.1 ppm by weight and 4.1 ppm by weight, respectively, while the impurity at 25.12 min was not detected. In a crude laurolactam and a product laurolactam, the impurities at 31.3 min and 31.7 min were contained in 2.1 ppm by weight and 4.0 ppm by weight, and 0.3 ppm by weight and 0.6 ppm by weight, respectively.