1-Methylpiperazine → HCID 20554355, compound

Participants

Reaction Conditions

Reaction Steps

2.6 g (0.0266 mol) of N-methylpiperazine are added dropwise at 50° C., in the course of 15 minutes, to a suspension of 4.0 g (0.0133 mol) of 11-chloroacetyl-6-methyl-5,6-dihydropyrimido[4,5-b][1,5]benzodiazepin-5-one in 30 ml of absolute benzene, and the mixture is stirred for a further 1.5 hours at 70° C. After cooling, the mixture is poured into 100 ml of saturated sodium bicarbonate solution and is extracted once with 50 ml of ethyl acetate and twice with 100 ml, each time, of chloroform. After drying, the organic phase is concentrated in vacuo, and the liquid residue is induced to crystallize by means of ether. It is purified by filtering through neutral silica gel (elution with chloroform) and evaporating the filtrate; yield: 2.7 g, m.p. 183° to 185° C.

Provenance & Evidence