反应详情

A solution of 4-methoxy-2-methylbenzonitrile (5.0 g, 33.97 mmol) in DCM (150 mL) is cooled down to 0° C. before adding dropwise a 1M BBr3 in DCM solution (136 mL, 136 mmol). The reaction mixture is allowed to reach rt and stirring is then continued at 45° C. for 5 days. Ice water (500 mL) is then added and the reaction mixture is stirred for 1 h before sat. aq. NaHCO3 (250 mL) is added. The mixture is extracted with DCM (200 mL then 4×100 mL) and the combined org. extracts are dried over MgSO4, filtered and evaporated to give the title compound as a brown solid (4.7 g); LC-MS: tR=0.76 min. 1H NMR (D6-DMSO): δ 2.38 (s, 3H), 6.73 (dd, J=8.5, 2.0 Hz, 1H), 6.79 (d, J=2.0 Hz, 1H), 7.55 (d, J=8.5 Hz, 1H), 10.49 (s, 1H).

1. customto reach rt
2. additionis added
3. extractionThe mixture is extracted with DCM (200 mL
4. dry with materialextracts are dried over MgSO4
5. filtrationfiltered
6. customevaporated