- Br?nsted acid-catalyzed chlorination of aromatic carboxylic acids
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The chlorination of aromatic carboxylic acids with SOCl2 has been effectively performed by reacting with a Br?nsted acid as the catalyst. Based on this discovery, an efficient catalytic method that is cheaper than traditional catalytic methods was developed. 20 substrates were chlorinated offering excellent yields in a short reaction time. And the SOCl2/Br?nsted acid system has been used in a larger scale preparative reaction. A dual activation mechanism was proposed to prove the irreplaceable system of SOCl2/Br?nsted acid.
- Yu, Zhiqun,Yao, Hongmiao,Xu, Qilin,Liu, Jiming,Le, Xingmao,Ren, Minna
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p. 685 - 689
(2021/04/09)
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- Synthesis method of zoalene
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The invention discloses a synthesis method of zoalene, belonging to the technical field of pharmaceutical engineering. The method comprises the following steps: A. nitration process, B. acylating chlorination process, and C. ammonifying process, wherein in the step A, a process of recycling concentrated sulfuric acid is set, specifically, the collected waste acid is treated by reduced pressure distillation and is concentrated, sulfur trioxide is then added into the treated waste acid, and the newly prepared concentrated sulfuric acid is added into a reaction kettle again for carrying out a nitration reaction; in the step C, a process of recycling waste ammonia water is set. By recycling and reusing raw materials, the method does not cause accumulative increment of sulfuric acid and ammonia water, thus improving the utilization rate of the raw materials and lowering the production cost; furthermore, the method reduces the treatment cost of the waste acid and the waste ammonia water and greatly reduces the discharge amount of waste water, thus having an important significance for environmental protection.
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- Process for formulating a synthetic drug for use in animal feed, and resulting formulation
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A method of formulating a synthetic drug for use in animal feed, for the purpose of reducing carry-over of the synthetic drug to subsequent lots of animal feed in the feed mill.
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