Boron tribromide → 6-Hydroxyquinoline-3-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

6-Methoxyquinoline-3-carboxylic acid (2.5 g, 12.3 mmol) was suspended in anhydrous dichloromethane (20 mL) under nitrogen; the suspension was cooled to −78° C. A solution of BBr3 in dichloromethane (100 mL of 1M solution, 100 mmol) was added dropwise. The mixture was stirred for 30 min at −78° C., warmed slowly to RT, and allowed to stir at room temperature overnight. The reaction was quenched by dropwise addition of ice-water. The resulting solids were collected by filtration, and washed with water to yield 3.2 g (97%) of 6-hydroxyquinoline-3-carboxylic acid as an HBr salt. LCMS: >98%; MS: 190.27 (M+1, free base).

Provenance & Evidence