Guanidine Hydrochloride → 2,4-diamino-5-(7,8-dimethoxy-2H-1-benzopyran-5-ylmethyl)pyrimidine

Participants

Reaction Steps

2-(7,8-Dimethoxy-2H-1-benzopyran-5-ylmethyl)-3-morpholino acrylonitrile (562 g, 1.64 mol) and aniline hydrochloride (234 g, 1.80 mol) were refluxed in SD3A (2.4 L) for one hour. The reaction was cooled, and guanidine hydrochloride (313 g, 3.28 mol) and sodium methoxide (275 g, 5.08 mol) were added. After continued reflux, the product crystallized from the cooled reaction mixture. Filtration followed by water wash (2 L) gave 2,4-diamino-5-(7,8-dimethoxy-2H-1-benzopyran-5-ylmethyl)pyrimidine (220 g, 42.7%). Crystallization from ethanol-water gave title compound, mp 235°-238°, identical to the product of Example 1C.

Provenance & Evidence