反应详情

Morpholine-4-carboxamidine hydrobromide (0.267 g) and 4-(2-ethoxycarbonylacetyl)-piperidine-1-carboxylic acid tert-butyl ester (0.38 g, 1.27 mmol) were stirred in ethanol (10 mL) and diazobicycloundecane (285 μl) was added. The reaction stirred for 18 hours at room temperature. The ethanol was removed under reduced pressure and water (25 mL) was added. The solution was acidified (to pH=4) with acetic acid. The product was extracted with dichloromethane (4×30 mL). The dichloromethane was removed and crude product was purified twice on silica gel (Combiflash), eluting with 10% methanol in dichloromethane to provide 4-(6-hydroxy-2-morpholin-4-ylpyrimidin-4-yl)-piperidine-1-carboxylic acid tert-butyl ester (0.15 g, 40.5% yield) as a white solid. 1H NMR (300 MHz, CDCl3/TMS): δ=5.63 (s, 1H), 4.25-4.05 (m, 2H), 3.75 (m, 8H), 2.75-2.65 (m, 2H), 2.47-2.35 (m, 1H), 1.00-1.75 (m, 2H), 1.70-1.50 (m, 2H), 1.46 (s, 9H). 13C NMR (75 MHz, CDCl3/TMS): δ=173.35, 166.87, 154.96, 154.06, 98.88, 79.70, 66.72, 45.13, 44.24, 30.64, 28.82, 27.58.

1. customThe ethanol was removed under reduced pressure and water (25 mL)
2. additionwas added
3. extractionThe product was extracted with dichloromethane (4×30 mL)
4. customThe dichloromethane was removed
5. customcrude product was purified twice on silica gel (Combiflash)
6. washeluting with 10% methanol in dichloromethane