476660-71-6

General procedure for the synthesis of 6-bromo-4-chloro-7-methoxyquinolin-4-ol from 6-bromo-7-methoxyquinolin-4-ol: 6-bromo-7-methoxyquinolin-4-ol (4.17 g, 16.4 mmol) was dissolved in phosphorus trichloride (8 mL, 82 mmol) and the reaction was stirred for 1 h at 110 °C. The reaction was carried out in aqueous solution of saturated sodium carbonate. Upon completion of the reaction, the mixture was cooled to room temperature and slowly poured into ice-cooled saturated aqueous sodium carbonate solution with stirring. The solid product in the resulting suspension was collected by filtration, washed well with water and subsequently dried under vacuum overnight to afford the target compound 6-bromo-4-chloro-7-methoxyquinoline (4.6 g, 16 mmol, 97% yield).LCMS assay: retention time (RT) = 1.18 min, mass spectrum (ESI+) m/z: 272, 274 [M+H] +.

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