Ag-Assisted Fluorination of Unprotected 4,6-Disubstituted 2‑Aminopyrimidines with Selectfluor

A direct
fluorination of 4,6-disubstituted 2-aminopyrimidines with
Selectfluor in the presence of Ag­(I) is presented, affording the corresponding
4,6-disubstituted 5-fluoro-2-aminopyrimidines with acceptable to high
yield. Ag­(I) is crucial for this chemoselective fluorination process.
The transformation of 4,6-diphenyl 5-fluoro-2-aminopyrimidine into N-(5-fluoro-4,6-diphenylpyrimidin-2-yl)-4-methyl­benzene­sulfonamide
is discussed, and the reaction mechanism is investigated, as well.