Yield: 66%

Reaction Conditions:

with potassium fluoride;tetrabutylammomium bromide in sulfolane

Steps:

2.a a)
a) Preparation of 4,6-Difluoropyrimidine STR13 A mixture of 4,6-dichloropyrimidine (223.5 g, 1.5 mol), potassium fluoride (279.6 g, 4.8 mol) and tetrabutylammonium bromide (6.0 g, 0.0186 mol) in sulfolane (1 L) is heated at 180-190° C. for 3.5 hours and distilled to give the title product as a white liquid (115 g, 66% yield).

References:

American Cyanamid Company US5977363, 1999, A