Hydrochloric Acid → Isopropanol

Participants

Reaction Steps

Into a solution of N-cyclopropylmethyl-N-(2-ethyl-7-iodopyrazolo[1,5-a]pyridin e-3-yl)-N-(tetrahydro-2H-4-pyranylmethyl)amine (220 g, 501 mmol) in dimethyl carbonate (3600 mL) was dropped a solution of concentrated hydrochloric acid (48.5 mL, 575 mmol) in isopropanol (270 mL) at room temperature over a period of 20 minutes, and the mixture was further stirred at room temperature for about 15 hours. The reaction mixture was cooled in an ice water bath, and to the reaction mixture was added dimethyl carbonate (900 mL). This mixture was stirred for about 5 hours, and a precipitate was filtrated. The precipitate was washed with dimethyl carbonate (900 mL), and dried at 50° C. under reduced pressure, to obtain 250 g of a title compound as a solvate in dimethyl carbonate and isopropanol (yield: 93.7%).

Provenance & Evidence