The present invention relates to an improved process for the preparation of pure 2-(2- amino-1,3-thiazol-4-yl)-N-[4-(2-[(2R)-2-hydroxy-2-phenylethyl]amino]ethylphenyl]- acetamide of formula (1) substantially free of impurities. The present invention relates to the novel process of preparing intermediate (R)-1- Phenyl-2-[[2-(4-nitrophenyl)ethyl]amino]ethanol hydrochloride of formula (2) in high yield, which is useful in the preparation of mirabegron of formula (1). The process also relates to the preparation of pure α –form crystal of 2-(2-Amino- 1,3-thiazol-4-yl)-N-[4-(2-[(2R)-2-hydroxy-2-phenylethyl]amino]ethylphenyl]acetamide Mirabegron (1) without isolation of β-form.
本发明涉及一种改进的工艺,用于制备纯度高的2-(2-
氨基-1,3-
噻唑-4-基)-N-[4-(2-[(2R)-2-羟基-2-苯乙基]
氨基)
乙基苯基]-乙酰胺,其
化学式为(1),基本上不含杂质。本发明涉及一种新的工艺,用于高产率制备中间体(R)-1-苯基-2-[[2-(4-
硝基苯基)乙基]
氨基]
乙醇盐酸盐,其
化学式为(2),该中间体在制备化合物mirabegron的过程中很有用。该工艺还涉及制备纯度高的α-型晶体的2-(2-
氨基-1,3-
噻唑-4-基)-N-[4-(2-[(2R)-2-羟基-2-苯乙基]
氨基)
乙基苯基]乙酰胺mirabegron(1),而无需分离β-型晶体。