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

Participants

Reaction Conditions

Reaction Steps

Guanidine hydrochloride (11.46 g, 0.12 mole) in methanol (25 mL) was added to sodium methoxide (6.55 g, 0.12 mole) in methanol (40 mL) and the resultant sodium chloride was filtered and washed with methanol (10 mL). The guanidine solution was added to 3-(7,8-dimethoxy-2H-1-benzopyran-5-yl)-2-methoxymethylpropenenitrile (11.5 g, 0.04 mole) and the mixture heated at reflux for 2 hr. Cooling the mixture at 3° C. provided 5.38 g of yellow solid in two crops. HPLC assayed yield of 28.6%. A sample recrystallized from alcohol/water gave mp 232°-4° C.

Provenance & Evidence