is crystallized from ethanol preparation of 17 to a solution of 2 5 dibromo 1 4 dihexylbenzene 33 mmol in tetrahydrofuran is added magnesium turnings 1 9 g 80 mmol under argon the resulting grignard reagent solution is slowly dropped into a stirred solution of trimethyl borate 38 ml 330 mmol in tetrahydrofuran at u2212 78 u00b0 c for 2 h and the resulting solution is warmed to room temperature and stirred for 2 days the reaction mixture is poured over a 5 sulfuric acid crushed ice solution while stirring and the mixture is extracted with ether the organic layer is separated and condensed and the resulting solid is recrystallized from hexane acetone this solid is then stirred with 1 2 ethanediol 50 mmol in toluene for 10 h and the product is purified by chromatography preparation of 2 amino 4 u2032 bromobenzophenone a 1 l round bottomed flask is charged with aluminum trichloride 2 1 mol and bromobenzene 3 1 mol and the resulting solution is cooled to u2212 5 u00b0 c under nitrogen a solution of 12 1 52 kg 8 4 mol in bromobenzene 1 0 kg 10 mol is slowly added and the mixture is allowed to stir for an additional hour before being poured over 1 kg of ice the resulting solid is collected by filtration and dissolved in methylene chloride 600 ml the resulting solution is filtered and the mother liquor.