A mixture of trifluoromethanesulfonic acid 4-[2-methyl-4-(2,4,6-trimethylphenylamino)-pyrimidine-5-sulfonyl]-phenyl ester (146 mg, 0.283 mmol), zinc cyanide (66 mg, 0.57 mmol), and DMF (2 mL) was degassed with N2 for 10 min, and then Pd(PPh3)4 (16 mg, 0.014 mmol) was added. The mixture was stirred at 80° C. under N2 for 2 h and then cooled to room temperature. The reaction mixture was treated with saturated aqueous NaHCO3, and extracted (3×) with EtOAc. The combined organic layers were washed with brine, dried over Na2SO4, filtered and concentrated in vacuo. The residue was purified by chromatography on silica gel (67:33 hexanes/EtOAc) to provide the target compound (108 mg, 97%) as a white solid: mp 258–260° C.; 1H NMR (500 MHz, CDCl3) δ 8.76 (s, 1H), 8.21 (br s, 1H), 8.08 (d, J=8.6 Hz, 2H), 7.84 (d, J=8.6 Hz, 2H), 6.92 (s, 2H), 2.40 (s, 3H), 2.31 (s, 3H), 2.00 (s, 6H); ESI MS m/z 393 [(M+H)+, calcd for C21H21N4O2S, 393.1].
