Yield:-

Reaction Conditions:

with hydrogenchloride in tetrahydrofuran;

Steps:

136 Preparation of 1-(3,5-Difluoro-4-methoxyphenyl)-2,2,2-trifluoroethanone

Example 136
Preparation of 1-(3,5-Difluoro-4-methoxyphenyl)-2,2,2-trifluoroethanone
Isopropyl magnesium chloride lithium chloride complex (22.0 mL, 28.02 mmol) was added dropwise to a stirred solution of 5-bromo-1,3-difluoro-2-methoxybenzene (5.0 g, 22.42 mmol) at -5° C. in THF (100 mL) and the reaction mixture was stirred at same temperature for 30 min.
Methyl triflouroacetate (3.67 g, 28.69 mmol) was added dropwise and then the reaction mixture was stirred at ambient temperature for 2 h.
A 2 N HCl solution (200 mL) was added to quench the reaction and then it was extracted with diethylether.
The organic combinded layers were washed with brine dried (Na₂SO₄), filtered and concentrated to afford the title compound (5.4 g, crude) as a yellow liquid.
The material was taken on to next step without further purification. ¹H NMR (400 MHz, CDCl₃) δ 7.68-7.60 (m, 2H), 4.19 (s, 3H); ESIMS m/z 240.1 ([M]⁺).

References:

US2014/171314,2014,A1 Location in patent:Page/Page column