1-Butanol → Terazosin

Participants

Reaction Steps

To a solution of n-butanol (316 ml), water (24 ml) and N-(2-tetrahydrofuroyl)piperazine (20 g) were added, while stirring, 4-amino-2-chloro-6,7-dimethoxyquinazoline (22.2 g). The reaction mixture was heated to reflux and the reflux was maintained for about 9 hours. Then the reaction mixture was cooled to room temperature and stirred at this temperature for about 10-12 hours. The crystals were collected by filtration, washed with n-BuOH and dried in vacuo at 40-50° C. to yield 40.1 g (94%) of Terazosin.HCl dihydrate. The product of this example was characterized by XRD and DSC melting point as shown in FIGS. 1 and 2 and in Table I as Trial H. This procedure was repeated in n-butanol using the water volumes indicated in Table I and yielding the results indicated for Trials G, I and J.

Provenance & Evidence