1-Bromo-2-(1,1-difluoroethyl)benzene synthesis

Yield: 100%

Reaction Conditions:

with 4-tert-butyl-2,6-dimethylphenylsulfur trifluoride;pyridine hydrofluoride in dichloromethane at 23; for 18 h;

Steps:

14 Example 14: Preparation of 1-bromo-2-(1,1-difluoroethyl)benzene (C18)
To a solution of 1-(2-bromophenyl)ethanone (1.36 mL, 10.1 mmol) and 4-tert- butyl-2,6-dimethylphenylsulfur trifluoride (5.03 g, 20.1 mmol) in dry DCM (20.1 mL) was added pyridine hydrofluoride (1.23 mL, 13.7 mmol) in a dry 50 mL Fisher Brand polypropylene tube. The reaction mixture was stirred at 23 °C for 18 h. The reaction mixture was added slowly to a solution of saturated aqueous sodium bicarbonate at 0 °C. The mixture was extracted with DCM. The organic layer was dried with Na2SO4 and concentrated under vacuum. Purification by Kugelrohr distillation provided the title compound as a colorless oil (2.72 g, 100%):¹H NMR (500 MHz, CDCl3) d 7.65- 7.57 (m, 2H), 7.35 (t, J = 7.6 Hz, 1H), 7.25 (td, J = 7.6 Hz, 1H), 2.04 (t, J = 18.4 Hz, 3H);¹⁹F NMR (471 MHz, CDCl3) d -87.32.

References:

DOW AGROSCIENCES LLC WO2021/11722, 2021, A1 Location in patent:Page/Page column 82-83