Hexane → 4-(trifluoromethyl)benzo[c][1,2]oxaborol-1(3H)-ol

Participants

Reaction Conditions

Reaction Steps

To a 2.5 M solution of n-BuLi in hexane (27.81 mL, 69.53 mmol) in dry THF (30 mL), cooled to −78° C. and under an Argon atmosphere was added a solution of (2-bromo-6-(trifluoromethyl)phenyl)methanol (CXXIX) (5.49 g, 23.16 mmol) in dry THF (30 mL) dropwise very slowly. The reaction mixture was stirred at −78° C. for 2 h before adding trimethyl borate (3.88 mL, 34.76 mmol). The reaction mixture was stirred at −78° C. for an additional 30 min, and then allowed to warm up slowly to room temperature and stirred overnight. The reaction was then cooled to 0° C. and slowly quenched with 2 M HCl and stirred for 2.5 h at room temperature. The reaction mixture was extracted with EtOAc and the organic layer was dried over anhydrous MgSO4. The solvent was removed under reduced pressure and the crude product was purified by silica gel chromatography using (100:1 DCM/MeOH) to give 4-(trifluoromethyl)benzo[c][1,2]oxaborol-1(3H)-ol (CXXX) as an orange oil (1.17 g, 5.79 mmol, 25% yield). ESIMS found for C8H6BF3O2 m/z 201.4 (M−H).

Provenance & Evidence