反应详情

To a solution of (S)-tetrahydro-1-methyl-3,3-diphenyl-1H,3H-pyrrolo[1,2-c]- [1,3,2]-oxazaborole-borane (6.06 mmol) in CH2Cl2 (6 mL) at −20° C. was added a solution of 3-nitroacetophenone (6.06 mmol) in CH2Cl2 (6 mL) in a dropwise fashion over 30 min. The resulting mixture was stirred 45 min. longer then poured into cold methanol (−20° C.), and this mixture allowed to stir overnight while warming to room temperature. The mixture was then concentrated in vacuo then more methanol (100 mL) added and concentrated, and then added another 100 mL methanol and concentrated. The resulting crude was purified on silica gel in 60:40 hexanes:ethyl acetate to yield 0.98 g of the title compound. 1H NMR (500 MHz, CDCl3): δ 8.22 (m, 1H); 8.08 (m, 1H); 7.69 (d, J=7.8 Hz, 1H); 7.50 (t, J=7.8 Hz, 1H); 5.00 (m, 1H); 2.62 (s, 1H); 1.53 (d, J=7.1 Hz, 3H).

1. stirringto stir overnight
2. concentrationThe mixture was then concentrated in vacuo
3. additionmore methanol (100 mL) added
4. concentrationconcentrated
5. additionadded another 100 mL methanol
6. concentrationconcentrated
7. customThe resulting crude was purified on silica gel in 60:40 hexanes