Mix 5-fluoro-2-piperazinyl-pyrimidine (900 g), 5-acetoxymethyl-2-phenyl-1H-imidazole (1.17 Kg, 1.1 equivalents), DMAP (N,N-dimethylaminopyridine, 30 g), toluene (7.2 L), ethanol (1.8 L) and triethylamine (1.095 L) at 20-25° C., and heat the mixture with stirring at 50-55° C. until the reaction is complete (typically about 20-25 hours). Then add water (3.75 L) and cool the resulting suspension to 0-50° C. Filter off the product, wash it with water (6×1.4 L) and cold toluene (3×700 ml), and dry it under vacuum at 50-55° C. to constant weight.
