2,5-DIFLUOROTHIOBENZAMIDE synthesis

Yield:1029623-72-0 99%

Reaction Conditions:

with pyridine;ammonium sulfide;triethylamine in water at 50; for 5 h;

Steps:

1

Synthesis of 2,5-difluorobenzothioamide; A stirred solution of 2,5-difluorobenzonitrile (25 g, 180 mmol) in pyridine (90 mL) was treated with 20 wt % ammonium sulfide in water (67.4 mL, 198 mmol) and triethylamine (27.4 mL, 198 mmol). The reaction mixture was stirred at 50° C. for 5 hr until the reaction was complete. After cooling to room temperature, the mixture was diluted with cold water and extracted with EtOAc. The organic layer was separated, then washed with H₂O (×3), brine (×3), then dried over anhydrous Na₂SO₄, filtered, and evaporated under reduced pressure to give the crude product. Purification on silica gel column (20% EtOAc in hexanes) to afford 2,5-difluorobenzothioamide as yellow solid (31.0 g, 99%). ¹H NMR (CDCl₃, 300 MHz): δ 7.12 (m, 2H), 7.90 (br, 2H), 8.08 (m, 1H). LC/MS (uplc): MH⁺174.0, 0.64 min.

References:

US2011/256128,2011,A1 Location in patent:Page/Page column 13; 23-24