Yield:-

Reaction Conditions:

with sodium methylate in methanol;

Steps:

16.3

To a solution of 2-fluoro-benzohydroxymoyl chloride (1.79 g) in methanol (10 mL) were added a solution of sodium methyl acetoacetate in methanol (prepared with methyl acetoacetate [1.85 mL] and a solution of sodium methoxide in methanol [about 1 equivalent]) at room temperature. After stirring at 60° C. for 1 hour, the reaction mixture was cooled to room temperature followed by addition of tetrahydrofuran (10 mL) and 2 N sodium hydroxide aqueous solution. After stirring at room temperature for 2 hours, the reaction mixture was concentrated to remove the organic solvent. The reaction mixture was washed twice with toluene and made acidic with 2 N hydrochloric acid. The produced solid was collected by filtration, washed with water, and dried to obtain the title compound (1.47 g) as a light brown solid.

References:

US2009/36450,2009,A1 Location in patent:Page/Page column 31