发明授权
US06316661B1 Process for the production of 2,3,5-trimethylhydroquinone diesters
失效
制备2,3,5-三甲基氢醌二酯的方法
- 专利标题: Process for the production of 2,3,5-trimethylhydroquinone diesters
- 专利标题(中): 制备2,3,5-三甲基氢醌二酯的方法
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申请号: US09493065申请日: 2000-01-28
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公开(公告)号: US06316661B1公开(公告)日: 2001-11-13
- 发明人: Steffen Krill , Horst Weigel , Klaus Huthmacher , Nongyuan Shi , Georg Markowz , Volker Hafner
- 申请人: Steffen Krill , Horst Weigel , Klaus Huthmacher , Nongyuan Shi , Georg Markowz , Volker Hafner
- 优先权: DE19903269 19990128
- 主分类号: C07C6900
- IPC分类号: C07C6900
摘要:
A process for the production of 2,3,5-trimethylhydroquinone diesters by aromatization of 2,6,6-trimethyl-2-cyclohexene-1,4-dione (4-oxoisophorone, ketoisophorone, KIP) with an acylating agent and an acidic soluble or insoluble catalyst, which process may be operated alternatively continuously or discontinuously. The process includes the following steps: a) a carboxylic anhydride having a C1 to C4 alkyl residue is used as the acylating agent, b) after the reaction, a proportion of the resultant carboxylic acid is optionally removed by distillation, c) the reaction solution is cooled, d) the product which has crystallized out is separated and washed, and e) the filtrate is returned to step a).