| abstract |
Form B ethyl [(7S) -7-[(2R) -2- (3-chlorophenyl) -2-hydroxyethylamino] -5,6, which exhibits advantageous physical properties for pharmaceutical production A process for producing 7,8-tetrahydronaphth-2-yloxy] acetate hydrochloride is provided. Ethyl [(7S) -7-[(2R) -2- (3) in a solvent selected from propan-2-ol, 2-methylpropan-2-ol, and butan-2-ol. -Chlorophenyl) -2-hydroxyethylamino] -5,6,7,8-tetrahydronaphth-2-yloxy] acetate, add concentrated hydrochloric acid solution, add a small amount of B-type seed crystals, and cool. By [Selection figure] None |