摘要
环己烯的制备是大学基础有机化学经典实验之一,一般采用浓硫酸催化环己醇脱水制备环己烯。为了建立环己烯的绿色化合成方法,采用固体杂多酸—磷钼酸催化环己醇的脱水反应。在配置刺形分馏柱和直型冷凝管的圆底烧瓶里加入一定量的环己醇和3 mol%的磷钼酸催化剂,将反应物置于油浴加热165~175°C,蒸出环己烯和水的混合物。反应终止后催化剂不经任何处理,可以继续高效催化环己醇脱水生成环己烯,磷钼酸催化剂可以循环使用3次以上而不失活,该方法具有催化效率高、催化剂可循环使用、合成绿色化等特点。将环境友好型的固体酸代替强腐蚀性的液体酸应用于有机合成实验教学中,不仅降低了学生在实验操作过程中的安全隐患,而且有利于给学生树立绿色化学的教学理念。
The preparation of cyclohexene from the dehydration reaction of cyclohexanol catalyzed by concentrated sulfuric acid is one of the classic organic synthetic experiments for college students. In order to establish a green synthesis of cyclohexene,solid heteropoly acid-phosphomolybdic acid was adopted to catalyze the dehydration reaction of cyclohexanol. In the round-bottom flask equipped with Vigreux column and condenser-west tube,cyclohexanol and 3mol% phosphomolybdic acid were added,and the mixture was heated at 165- 175 ℃ in oil-bath to evaporate the mixture of cyclohexene and water. After the end of the reaction,phosphomolybdic acid could be directly reused to catalyze the dehydration reaction of cyclohexanol without any treatment,and it could be recycled for three times without significant loss of catalytic activity. This method has the advantages of high catalytic efficiency,recycling catalyst and green synthesis. It is favorable for students to set up the concept of ＂green chemistry＂accompanying the introduction of environmentally friendly solid acids in organic synthesis experiment teaching.
出处
《实验室研究与探索》
CAS
北大核心
2015年第10期30-31,209,共3页
Research and Exploration In Laboratory
基金
国家自然科学基金(21302233)
湖北省高等学校省级教学研究项目(JYS12009)
中南民族大学国家级民族药学实验教学中心和大学生创新创业训练计划项目
关键词
绿色化学
环己烯
磷钼酸
green chemistry
cyclohexene
phosphomolybdic acid
