Development of an Improved Synthetic Process of Clonazepam by Preventing the Formation of a Trimeric Compound in the Presence of HCl
作者:Xuezhi Gao、Jiajian Xu、Chunfeng Liu、Peng Peng、Chuanmeng Zhao、Mengke Chen、Pengcheng Qiu、Fuli Zhang
DOI:10.1021/acs.oprd.2c00023
日期:2022.4.15
results in a low yield and purity. 2-Amino-N-(2-(2-chlorobenzoyl)-4-nitrophenyl) acetamide hydrochloride (7·HCl) was a key intermediate separated in the improved process, and the method of its synthesis with high purity to avoid the production of 9 was further reported. The improved process performed better in terms of efficiency and robustness. Besides, the high-performance liquid chromatography purity
开发了改进的氯硝西泮合成工艺,确定了关键参数。首次分离鉴定了采用一锅法制备的氯硝西泮三聚体中间体( 9 )。进一步证实,采用一锅法制备氯硝西泮时, 9在高温下解聚是定速步骤,收率低,纯度低。2-氨基-N- (2-(2-氯苯甲酰基)-4-硝基苯基)乙酰胺盐酸盐(7·HCl)是改进工艺中分离的关键中间体,其合成方法纯度高,避免产生9被进一步报道。改进的过程在效率和稳健性方面表现更好。此外,采用改进方法得到的氯硝西泮的高效液相色谱纯度和总收率分别为99.98%和57%。