反应详情

To a solution of Boc-1-ethyl-3-[6-fluoro-5-[2-(1-hydroxy-1-methyl-ethyl)pyrimidin-5-yl]-7-[(2R)-tetrahydrofuran-2-yl]-1H-benzimidazol-2-yl]urea dibenzyl phosphate (26) (11.9 g, 15.09 mmol) in DCM (300 mL) at 23° C. was added water (2.325 mL, 129.1 mmol) then TFA (3.441 g, 2.325 mL, 30.18 mmol). After 1 h, only partial conversion was observed by tlc, so more TFA (3.441 g, 2.325 mL, 30.18 mmol) was added. After a further 2.5 h, MeOH (2 mL) was added and the mixture stirred a further 18 hours. The reaction mixture was washed with 1:1 brine:saturated aqueous sodium bicarbonate (200 mL). The aqueous layer was re-extracted with DCM (150 mL), the organic layers combined, then dried (over magnesium sulfate), filtered and concentrated in vacuo. The resulting residue was re-dissolved in EtOAc (200 mL) washed with water (150 mL) and brine (100 mL), then dried (magnesium sulfate) filtered and concentrated to give (R)-dibenzyl 2-(5-(2-(3-ethylureido)-6-fluoro-7-(tetrahydrofuran-2-yl)-1H-benzo[d]imidazol-5-yl)pyrimidin-2-yl)propan-2-yl phosphate (24) (10.21 g, 14.83 mmol, 98.27%) as a white solid. ESMS (M+1)=689.4; 1H NMR (300 MHz, CD3OD) δ 8.88 (d, J=1.6 Hz, 2H), 7.37 (d, J=6 Hz, 1H), 7.30 (m, 10H), 5.38-5.33 (m, 1H), 5.12-5.01 (m, 4H), 4.24 (dd, J=6.8, 14.9 Hz, 1H), 3.98 (dd, J=6.9, 15.1 Hz, 1H), 3.35-3.27 (m, 3H), 2.52 (q, J=5.9 Hz, 1H), 2.14-2.05 (m, 2H), 1.91 (s, 6H) and 1.22-1.14 (m, 3H) ppm.

1. additionwas added
2. waitAfter a further 2.5 h
3. washThe reaction mixture was washed with 1:1 brine
4. extractionThe aqueous layer was re-extracted with DCM (150 mL)
5. dry with materialdried (over magnesium sulfate)
6. filtrationfiltered
7. concentrationconcentrated in vacuo
8. dissolutionThe resulting residue was re-dissolved in EtOAc (200 mL)
9. washwashed with water (150 mL) and brine (100 mL)
10. dry with materialdried (magnesium sulfate)
11. filtrationfiltered
12. concentrationconcentrated