2,2-DIMETHYL-3'-TRIFLUOROMETHYLPROPIOPHENONE synthesis

Yield:898766-39-7 1.1 g

Reaction Conditions:

Stage #1: 3-bromo-1-trifluoromethylbenzenewith magnesium in tetrahydrofuran at 20; for 1 h;Inert atmosphere;
Stage #2: pivaloyl chloride in tetrahydrofuran at 0; for 1 h;

Steps:

86 Reference Production Example 86

Reference Production Example 86 (0852) Under nitrogen atmosphere, to a mixture of 30 mL of tetrahydrofuran and 0.73 g of magnesium, 4.2 mL of 1-bromo-3-trifluoromethylbenzene was slowly added dropwise at 0°C, followed by stirring at room temperature for one hour. The obtained solution was slowly added dropwise in a three-necked flask containing 4.7 g of pivaloyl chloride and 50 mL of tetrahydrofuran at 0°C, followed by stirring for one hour. After completion of the reaction, an aqueous saturated ammonium chloride solution was added, and the mixture was extracted three times with ethyl acetate, dried over anhydrous sodium sulfate, and then dried under reduced pressure to obtain a crude product. The obtained crude product was subjected to silica gel column chromatography to obtain 1.10 g of 2,2-dimethyl-1-(3-trifluoromethylphenyl)propan-1-one (C86A). ¹H-HMR (CDCl₃) δ (ppm): 7.92 (1H, s), 7.86 (1H, d, J = 7.1 Hz), 7.72 (1H, d, J = 7.8 Hz), 7.54 (1H, t, J = 7.8 Hz), 1.36 (9H, s).

References:

EP2927218,2015,A1 Location in patent:Paragraph 0852