Synthesis
In the modification of the literature procedure, benzoyl chloride (14.1g, 100 mmol) and 3-bromobenzonitrile (30.4g, 200 mmol) were dissolved in chlorobenzene (150 mL) under an argon atmosphere. To the solution, antimony(IV) chloride (29.9g, 100 mmol) was added drop-wise at 0 °C. The mixture was stirred for 20 min at room temperature, then heated at 100 °C for 2 h, and the resulting orange slurry of the oxadiazinium salt was cooled to –20 °C. With vigorous stirring, 28% NH3 aqueous solution (80 mL) was added to the slurry, and a white precipitate of desired compound was immediately formed. The resulting suspension was allowed to warm to room temperature. Chlorobenzene (100 mL) was added to the flask, and the same amount of chlorobenzene was removed by an azeotropic distillation. The mixture was subjected to hot filtration at 130 °C, and a residual solid was extracted twice with the same manner (chlorobenzene, 100 mL × 2). The combined filtrate was allowed to cool to ambient temperature, and MeOH (200 mL) was added. Resulting precipitate was collected by filtration and dried to give 2,4-bis(3-bromophenyl)-6-phenyl-1,3,5-triazine as a white solid (38.3 g, 82%).