Boron tribromide → 4H-1-Benzopyran-4-one, 3-(2,4-dihydroxyphenyl)-7-hydroxy-

Participants

Reaction Steps

At 0° C., a solution of 14 (1.0 g, 3.2 mmol) in CH2Cl2 was treated with BBr3 (16 mL, 16 mmol, 1 M in CH2Cl2) and the reaction mixture was allowed to stir at rt for 18 h. The reaction was quenched slowly with MeOH, concentrated and taken up in EtOAc. The EtOAc layer was washed with 2N HCl aq. And the EtOAc was dried over MgSO4, filtered, concentrated and chromatographed on silica gel (EtOAC/hexanes; 1:1) to yield 15 as a white solid (0.5 g).

Provenance & Evidence