72150-17-5Relevant articles and documents
A novel and practical asymmetric synthesis of eptazocine hydrobromide
Li, Ruipeng,Liu, Zhenren,Chen, Liang,Pan, Jing,Lin, Kuaile,Zhou, Weicheng
, p. 2340 - 2347 (2018)
In order to prepare eptazocine hydrobromide effectively, a novel, mild and practical asymmetric process was developed starting from 1-methyl-7-methoxy-2-tetralone under the catalysis of N-(p-trifluoromethylbenzyl)cinchonidinium bromide. The reaction conditions were optimized to obtain the product in excellent overall yield and purity.
Chiral resolution techinical method of etexastine hydrobromide
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, (2019/05/15)
The invention discloses a chiral resolution techinical method of etexastine hydrobromide. The techinical method comprises the following steps: taking racemic eptazocine as an initial raw material to carry out esterification with phthalic anhydride to obtain an etexastine carboxylic acid derivative, then carrying out salifying with a chiral phenylethylamine derivative for resolution to obtain a chiral intermediate, carrying out dissociating to remove chirality, carrying out degreasing to remove phthalic acid to obtain chiral eptazocine, adding hydrobromic acid for saltifying, and carrying out precipitating in an ethanol system to obtain the target product etexastine hydrobromide. According to the invention, the final compound is adopted for resolution, and resolution of an intermediate is avoided, so that the use of a highly toxic product ethyl chloroformate is greatly reduced, high-temperature high-pressure distillation operation is reduced, and the method is beneficial for productionpersonnel and the environment. The addition amount of the hydrobromic acid is 1.5 times of equivalent weight of the substrate, ethanol is used as a solvent system, and concentration is not needed after the acid is added, so that damage to the product by high temperature is avoided, impurities generated due to the fact that the target object is degraded at the high temperature is reduced, and colorof the product can be improved.
A hydrobromidum eptazocine preparation method
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Paragraph 0034; 0035; 0036; 0037; 0038, (2016/11/21)
The invention provides a method for preparing eptazocine hydrobromide. The method comprises the following steps: enabling a compound II, namely (1S,6S)-(-)-1,4-dimethyl-10-methoxy group-2,3,4,5,6,7-hexahydrogen-1,6-methylene-1H-4-benzo nonylbenzene to react in a hydrogen bromide solution, after reaction, drying reaction liquid by distillation at reduced pressure, drying by distillation at reduced pressure by adding water for multiple times and performing recrystallization refining for multiple times, and adding a certain amount of HBr solution during refining at the last time. The product color is qualified, the product is colorless and transparent after being dissolved in water, and the purity achieves more than 99.8 percent.