反应详情

To a stirred mixture of 2-bromo-N-(1-(tert-butyldimethylsilyloxy)-2-methylpropan-2-yl)-5H-pyrrolo[3,2-b]pyrazine-7-carboxamide in DMF (5 mL) was added chloromethyl pivalate (288 mg, 1.92 mmol) followed by K2CO3 (353 mg, 2.56 mmol). The mixture was stirred at room temperature for 16 hours, then poured into water and extracted with EtOAc (3×10 mL). The combined organic layers were washed with brine and dried over Na2SO4. After filtration and concentration, the residue was purified by column chromatography on silica gel eluting with petroleum ether/EtOAc (5:1, v/v) to give (2-bromo-7-(1-(tert-butyldimethylsilyloxy)-2-methylpropan-2-ylcarbamoyl)-5H-pyrrolo[3,2-b]pyrazin-5-yl)methyl pivalate (305 mg, 44% over two steps) as a yellow solid. MS: (M+H)+=541; 1H NMR (300 MHz, CDCl3): δ 8.41 (s, 1H), 8.33 (s, 1H), 7.84 (s, 1H), 6.20 (s, 2H), 3.71 (s, 2H), 1.49 (s, 6H), 1.15 (s, 9H), 0.90 (s, 9H), 0.09 (s, 6H).

1. extractionextracted with EtOAc (3×10 mL)
2. washThe combined organic layers were washed with brine
3. dry with materialdried over Na2SO4
4. filtrationAfter filtration and concentration
5. customthe residue was purified by column chromatography on silica gel eluting with petroleum ether/EtOAc (5:1