Sodium hydride → 4-(7-Methoxy-thiazolo[5,4-d]pyrimidin-2-ylcarbamoyl)-piperazine-1-carboxylic acid tert-butyl ester

참여 물질

반응 조건

반응 단계

A solution of 7-methoxy-thiazolo[5,4-d]pyrimidin-2-ylamine (3.5 g, 19.2 mmol) in tetrahydrofuran (100 mL) was treated with sodium hydride (60% in mineral oil, 2.3 g, 57 mmol) at 25° C. A slight evolution of gas was observed. The resulting purple slurry was warmed to 50° C. for 1 h. At this time, the reaction was cooled to 25° C. and was treated with N,N-diisopropylethylamine (10 mL, 57 mmol). The resulting mixture was stirred at 25° C. for 30 min. The mixture was then treated with a solution of 4-chlorocarbonyl-piperazine-1-carboxylic acid tert-butyl ester (4.73 g, 19 mmol) in tetrahydrofuran (20 mL) over a 10 min period. The reaction was stirred at 50° C. overnight. At this time, the reaction was concentrated in vacuo, diluted with methanol (100 mL) and absorbed onto silica gel (6 g). The silica gel was divided into two equal lots. ISCO chromatography (330 g, Silica, gradient elution 5/95 methanol/methylene chloride) afforded 4-(7-methoxy-thiazolo[5,4-d]pyrimidin-2-ylcarbamoyl)-piperazine-1-carboxylic acid tert-butyl ester (5.58 g, 74%) as an off-white solid; LRMS for C16H22N6O4S (M+H)+ at m/z=395. The NMR spectrum obtained on the sample is compatible with its structure.

출처 및 근거