Scheme 4. Synthesis of 2-Substituted Pyrimidine Compounds from Tables 4 and 5, Starting from Common Intermediate 18.
Reagents and conditions: (a) dimethylamine HCl, cesium carbonate, NMP, 180 °C, 1 h; (b) cyclic amine, DIPEA, NMP, 140–180 °C, 1–2 h; (c) pyrazole, cesium carbonate, NMP, 170 °C, 1 h; (d) 2,4-dimethyl-5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)thiazole, sodium carbonate, PdCl2(PPh3)2, 1,4-dioxane/water, 130 °C, 30 min; (e) 1-methyl-2-(tributylstannyl)-1H-imidazole, PdCl2(PPh3)2, 1,4-dioxane, 90 °C, 18 h; (f) bicyclic amine, DIPEA, NMP, 140 °C, 2–8 h.