Triethylamine → tert-Butyl 4-(6-chloro-5-nitropyrimidin-4-yl)piperazine-1-carboxylate

Participants

Reaction Steps

A solution of 1-[1,1-dimethylethoxycarbonyl]piperazine (1.88 g) in dichloromethane (30 ml) is added drop by drop over 1.5 hr to a solution of 4,6-dichloro-5-nitropyrimidine (1.94 g) and triethylamine (1.32 g) in dichloromethane (170 ml) at - 78°. After stirring an additional hr at -78°, the reaction is diluted with aqueous sodium bicarbonate (10%). The phases are separated, the organic phase is concentrated to a liquid which solidified on standing at 20°-25°. The solid is dissolved in chloroform and flash chromatographed on silica gel eluting with methanol/chloroform (1/99), pooling and concentrating the appropriate fractions gives the title compound, Anal. Calc for C13H18N5ClO4 ; MW=343.77: C,45.42; H,5.28; N,20.37; Cl,10.31. Found: C,45.52; H,5.40; N,20.34; Cl,10.36.

Provenance & Evidence