2-[Bis(tert-butoxycarbonyl)amino]-5-(2′-methylthiophenyl)pyrimidine (2.13 g, 5.1 mmol) was dissolved in MeOH (20 mL) and cooled to 0° C. In a separate beaker, a solution of Oxone (5.49 g) was generated by dilution to 27 mL with water. A portion of this solution (17 mL, 5.6 mmol) was removed and adjusted to pH 4.2 with sat. Na3PO4 solution (4.7 mL). This mixture was added to the reaction and stirred 23 hours at room temp. The resulting mixture was diluted with water and extracted with CHCl3. The organics were combined, washed with water and brine, dried over Na2SO4, filtered, and evaporated. The crude product was chromatographed on silica gel (50-100% EtOAc/hexanes) to yield the sulfone (1.28 g, 56%). 1H NMR (CDCl3): δ8.81 (s, 2H), 8.28 (dd, 1H, J=7.6, J′=1.4), 7.72 (m, 2H), 7.39 (dd, 1H, J=7.3, J′=1.4), 2.76 (s, 3H), 1.50 (s, 18H).
