反应详情

6.1 g of anhydrous methanesulfonic acid were added to a stirred mixture of 27.1 g of doxazosin, 54 ml of N-methyl-2-pyrrolidone and 250 ml of methanol in a 500 ml three-neck round-bottom flask. The internal temperature rose to 30° C. during this, and a solution was produced. After the addition of methanesulfonic acid was complete, the reaction mixture was filtered into a second 500 ml three-neck round-bottom flask, and the filtrate was stirred for 5 h. After the end of the stirring time, the resulting precipitate was filtered off with suction and washed 2× with 50 ml of methanol each time. 45 g of moist doxazosin mesylate (modification D) were obtained. This corresponds to 28.5 g of dry substance and a yield of 86.7%.

1. customrose to 30° C.
2. customwas produced
3. filtrationthe reaction mixture was filtered into a second 500 ml three-neck round-bottom flask
4. filtrationAfter the end of the stirring time, the resulting precipitate was filtered off with suction
5. washwashed 2× with 50 ml of methanol each time