Yield:-

Reaction Conditions:

with bromine;acetic acid at 40; for 5 h;

Steps:

1

2-Fluoro-4-trifluoromethylacetophenone (1.03 g) was dissolved in acetic acid (5 ml) and warmed to 40 ° C.Bromine (880 mg) was slowly added dropwise to the solution,And the mixture was stirred as such for 5 hours. Hypo water was added to the reaction solution, and the mixture was extracted with ethyl acetate, dried and concentrated to give 2-bromo-1- (2-fluoro-4-trifluoromethylphenyl) ethanone.It was used for the next step without purification.2-Bromo-1- (2-fluoro-4-trifluoromethylphenyl) ethanone prepared in the preceding step was dissolved in ethanol (5 ml), 2-amino-5-trifluoromethylpyridine (520 mg) was added to the solution Additionally,And heated under reflux for 4 hours.The reaction solution was concentrated,The obtained residue was purified by column chromatography,To give the target compound (370 mg).

References:

JP2015/3906,2015,A Location in patent:Paragraph 0127