Phosphorus oxychloride → 4-Chloro-6-(3,4-dimethoxy-phenyl)-[1,5]naphthyridine-3-carboxylic acid ethyl ester

Participants

Reaction Conditions

Reaction Steps

A mixture of 6-(3,4-dimethoxy-phenyl)-4-hydroxy-[1,5]naphthyridine-3-carboxylic acid ethyl ester (Stage 249.1.3, 493 mg, 1.391 mmol) in POCl3 was stirred at 125° C. for 1.5 h. Then the RM was evaporated to dryness. The residue was quenched with saturated aqueous NaHCO3. The suspension was filtered, the cake was washed with water and dried in the vacuum oven to give the title compound as a brown solid. Used for next step without further purification. (HPLC: tR 3.80 min (Method A); M+H=373 MS-ES)

Provenance & Evidence