环己酮二乙缩酮的合成工艺研究

环己酮二乙缩酮广泛应用于医药中间体的合成,也可以用于合成1-乙氧基环己烯,继而用于合成高分子材料和医药中间体.其制备方法是以氯化铵为催化剂,原甲酸三乙酯为解水剂,由无水乙醇和环己酮缩合合成.此方法具有催化剂便宜易得,可回收,反应后处理方便,工业三废少,收率高等优点,是环境友好的清洁生产过程.今通过各种影响因素研究实验得出了合成的最佳工艺条件:环己酮用量为29.4 g (0.3 mol)时,环己酮与原甲酸三乙酯摩尔比1:1.2,环己酮与无水乙醇摩尔比1:3,催化剂0.006 mol,回流下反应,反应时间90 min,产品收率91.8%,产品纯度和结构由气相色谱、气质联用仪及核磁共振仪确定.

Studies on Synthesis of Cyclohexanone Diethyl Acetal

Cyclohexanone diethyl acetal is widely used as pharmaceutical intermediates, and it may be pyrolyzed to give 1-ethoxy cyclohexene which could be used in synthesizing both polymer material and pharmaceutical intermediates. Cyclohexanone diethyl acetal was prepared from cyclohexanone with anhydrous ethanol as reactant, ammonium chloride as catalyst, triethyl orthoformate as water scavenger. The proposed method, which is preferable for green process, has many advantages such as the catalyst used is cheap and easily obtained, the post treatment of the process is convenient, the process has few industrial waste and high yield, etc. The suitable technical conditions were investigated in detail, which include the effects of catalyst, reaction time and reactants mole ratio on yield. The results indicate that 91.8% yield could be obtained with the following optimal reaction conditions: cyclohexanone weight 29.4 g (0.3 mol), the mole ratio of cyclohexanone and triethyl orthoformate 1:1.2, the mole ratio of cyclohexanone and anhydrous ethanol 1: 3, the reaction time 90 minutes, the amount of catalyst 0.006 mole, and reaction with reflux. The purity and structure of the product was examined by GC GC-MS and NMR.