Boron tribromide → Methyl 5-hydroxybenzo[b]thiophene-2-carboxylate

Participants

Reaction Conditions

Reaction Steps

The above prepared 5-methoxy-benzo[b]thiophene-2-carboxylic acid methyl ester (0.199 g, 0.895 mmol) was dissolved in 6 mL of CH2Cl2, cooled to 0° C., and treated with BBr3 (1.79 mL of 1M solution in CH2Cl2, 2 eq.). After 2 additional h at 0° C., the reaction mixture was carefully poured onto crashed ice, twofold extracted with AcOEt, washed with water, dried over sodium sulfate, and evaporated to dryness. Flash chromatography (SiO2, hexane/AcOEt=7/3) yielded 0.145 g of the title compound as off-white solid.

Provenance & Evidence