Methanol → Bosentan

Participants

Reaction Steps

Methanol (200 mL) and dichloromethane (200 ml) were added to the bosentan potassium as obtained in Step 2. The mixture was heated to 50° C. to 55° C. The mixture was stirred for 20 minutes at the same temperature and dichloromethane (˜150 mL) was recovered at atmospheric pressure at 40° C. to 55° C. Ethyl acetate (800 mL) was added to the residue at 50° C. to 55° C. The reaction mixture was cooled to 20° C. to 25° C., stirred for 3 hours, filtered and washed with a mixture of methanol (20 mL) and ethyl acetate (80 mL). The solid obtained was dried under vacuum at 55° C. to 60° C. until the loss on drying was not more than 2.0% w/w to obtain the title compound.

Provenance & Evidence