2-Cyano-3,5-difluoropyridine synthesis

Yield:-

Reaction Conditions:

with polyethylene glycol 8000;potassium fluoride in dimethyl sulfoxide at 160; for 0.5 h;

Steps:

V Example V; 2-Cyano-3,5-difluoropyridine

[0172] 50 g (0.29 mol) of 2-cyano-3,5-dichloropyridine from Example IV, 33.6 g (0.58 mol) of potassium fluoride and 10 g of polyethylene glycol 8000 are mixed with 125 ml of DMSO and heated at 160° C. for 30 minutes. After cooling, the product is distilled out together with the DMSO under high vacuum, the distillate is added to water and, after extraction with toluene, dried over sodium sulfate. The product is reacted further as solution in toluene. [0173] Rf: 0.43 (cyclohexane/ethyl acetate=7:3)

References:

US2003/232842,2003,A1 Location in patent:Page 8