5-溴-2,4-二甲基苯酚

反应条件: temp:95.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: A 250-mL round bottomed flask is charged with 5-bromo-2,4-dimethylphenol (3.135 g, 15.6 mmol) and dimethylformamide (DMF) (50 mL). Potassium carbonate (23.7 g, 172 mmol) and bromobutene (15.8 mL, 156 mmol) are added and the reaction mixture is heated to 95° C. for 2 hr. After cooling to room temp, water (200 mL) is added. The product is extracted into ether (2×100 mL), and the combined organic fractions are washed with brine, dried over sodium sulfate and dried in vacuo. Yield=3.63 g (91.3%) of light yellow liquid. After cooling to room temp The product is extracted into ether (2×100 mL) the combined organic fractions are washed with brine dried over sodium sulfate dried in vacuo

反应条件: temp:-70.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: In a glovebox, 1,5-dibromo-2,4-dimethylbenzene (10.000 g, 37.9 mmol) is dissolved in dry THF (140 mL) in a one-neck round bottomed flask with a thermometer well. The flask is capped with a septum, and removed from the glovebox. Nitrogen purge is provided via a needle through the septum, and the solution is cooled to −70° C. using a dry ice/acetone bath. Butyllithium (BuLi) (1.6M in hexanes, 26 mL, 42 mmol) is added slowly, maintaining the temperature below −65° C. After stirring for 80 minutes at −70° C., trimethylborate (B(OMe)3) (4.2 mL, 37.9 mmol) is added slowly, maintaining the temperature below −62° C., and then the reaction is allowed to slowly warm to room temperature overnight. Solvents are removed on a rotovap, leaving a very pale yellow oily solid, which is dissolved in tetrahydrofuran (THF) (100 mL) and treated with hydrogen peroxide (H2O2) (30% aq, 13 mL) and sodium hydroxide (NaOH) (1M, 25 mL) for two hours. The reaction is then quenched with ammonium chloride (NH4Cl) (aq) and extracted into ether (2×100 mL). The organic fractions are combined, dried over sodium sulfate, filtered and dried in vacuo. Yield=6.60 g (86.7%) of pale yellow waxy solid. The flask is capped with a septum removed from the glovebox Nitrogen purge is provided via a needle through the septum maintaining the temperature below −65° C maintaining the temperature below −62° C. to slowly warm to room temperature overnight Solvents are removed on a rotovap leaving a very pale yellow oily solid, which The reaction is then quenched with ammonium chloride (NH4Cl) (aq) extracted into ether (2×100 mL) dried over sodium sulfate filtered dried in vacuo