4-(4′-Chloro-2′-(methylthio)-4,5′-bipyrimidin-2-ylamino)benzonitrile (35) (205 mg, 0.526 mmol) and ferric acetylacetonate (18.57 mg, 0.053 mmol) were dissolved in THF (3305 μl) and NMP (248 μl), then ethylmagnesium bromide (789 μl, 0.789 mmol) was added dropwise under nitrogen. The reaction was quenched with 1N HCl, then was extract with EtOAc. The organic extracts were combined, washed with brine, dried over sodium sulfate, then concentrated in vacuo. The crude product was dry-loaded onto silica gel and purified by Biotage™ silica gel chromatography [25 g SNAP column, 30% EtOAc/heptane to 100% EtOAc] to obtain 49 mg of the desired product (21%). 1H NMR (400 MHz, DMSO-d6) δ ppm 1.19 (t, J=7.58 Hz, 3 H) 2.59 (s, 3 H) 2.95 (q, J=7.58 Hz, 2 H) 7.25 (d, J=5.05 Hz, 1 H) 7.68-7.78 (m, 2 H) 7.95-8.03 (m, 2 H) 8.67-8.75 (m, 2 H) 10.33 (s, 1 H). MS (ES+): m/z=349.5 [M+1] (100). HPLC: tR=1.57 minutes over 3 minutes. Purity: 93% [HPLC (LC/MS) at 220 nm].
