反应详情

To a mixture of (4-Bromomethyl-1,6-dihydroxy-1,3-dihydro-benzo[c][1,2]oxaborol-3-yl)-acetic acid ethyl ester (0.5 mmol) in DCM (5 mL) was added diethylamine (5 mmol) and the mixture was stirred overnight at r.t. The crude product was evaporated, LiOH (75 mg) in THF/water/methanol (2:1:1, 5 mL) was added and stirred at r.t. for 1 h. The solvent was evaporated to give a residue, which was purified by HPLC, yielded 5 mg of desire product. MS (ESI) m/z: 294 [M+1]+; 1H NMR (300 MHz, CD3OD) δ 7.18 (s, 2H), 5.72-5.76 (dd, 1H), 4.20-4.45 (dd, 2H), 3.05-3.22 (m, 3H), 2.36-2.44 (dd, 1H), 1.40-1.45 (t, 3H), 1.30-1.34 (t, 3H).

1. customThe crude product was evaporated
2. additionLiOH (75 mg) in THF/water/methanol (2:1:1, 5 mL) was added
3. stirringstirred at r.t. for 1 h
4. customThe solvent was evaporated
5. customto give a residue, which
6. customwas purified by HPLC
7. customyielded 5 mg of desire product