4-Chloroquinoline-6-carboxylic acid ethyl ester synthesis

Yield:148018-34-2 67%

Reaction Conditions:

with trichlorophosphate at 120; for 3 h;

Steps:

10.42

Intermediate 41 (3 g 13.8 mmol) and POCl₂ (8 mL) were combined and stirred for 3 h at 120° C. The solvent was evaporated in vacuo and crushed ice was added. A biphasic mixture of Saturated aqueous NaHCO₃ and ethyl acetate was added. The layers were separated and the aqueous phase was extracted with ethyl acetate. The organic phases were combined, dried over solid Na2SO4, filtered, and the volatiles from the filtrate were evaporated in vacuo. The desired product was purified by Silica gel column chromatography (2.19 g, 67%).

References:

US2008/234267,2008,A1 Location in patent:Page/Page column 25