Yield:53839-71-7 88.2%

Reaction Conditions:

with dmap in N,N-dimethyl-formamide at 5 - 20; for 5 h;Industrial scale;Solvent;Reagent/catalyst;Temperature;

Steps:

3 Example 3
Industrial production Viaminate (III)
Example 3
Industrial production Viaminate (III)
In the reaction tank 400kg N, N-dimethyl formamide, 24 kg (145.4mol) benzocaine, 50kg4-dimethyl aminopyridine, then the 35 kg-Vitamin A chloride (109.8mol) diluted wiht proper amount of N,N-dimethyl formamide, was slowly added to the reaction tank at 5 °C -10 ° C. After completing the addition, the mixture was reacted at 15-20 °C for 5 hours, vacuum distillation, to separate out a large amount of solid after the tank, adding 60kg 95% ethyl acetate, stirring, cooling crystallization, centrifugation, washing, drying, get Viaminate finished 43.4 kg, yield 88.2%, purity 99.6%.

References:

Chongqing Shenghuaxi Pharmaceutical Co. , Ltd.;Li, Guoyang;Xie, Jianhua CN103159658, 2016, B Location in patent:Paragraph 0052; 0053

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