N-diphenylmethylene-2,6-diisopropyl-4-bromoaniline

Conditions: temp:160.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 40.7 g (0.195 mol) of tetraethoxysilane and 0.5 mL of sulfuric acid were added to a flask equipped with a distiller, containing 43.9 g (0.169 mol) of 4-bromo-2,6-diisopropylaniline and 24.8 g (0.130 mol) of benzophenone under a nitrogen atmosphere. The mixture was reacted by heating at 160° C. for 2 days while removing formed ethanol using the distiller. After the reaction, the resultant product was cooled to room temperature. Then, 200 mL of 1.0 M aqueous solution of potassium hydroxide was added to the resultant product and stirred for 10 minutes to obtain yellow precipitates. The obtained precipitates were filtered off and dissolved in 300 mL of ethyl acetate, and then dried over anhydrous magnesium sulfate. The solvent was removed by distillation under reduced pressure to obtain a yellow solid. Then, the yellow solid was recrystallized in hexane at −20° C. to obtain 42 g of N-diphenylmethylene-2,6-diisopropyl-4-bromoaniline compound. equipped with a distiller The mixture was reacted while removing formed ethanol using the distiller After the reaction to obtain yellow precipitates The obtained precipitates were filtered off dissolved in 300 mL of ethyl acetate dried over anhydrous magnesium sulfate The solvent was removed by distillation under reduced pressure to obtain a yellow solid Then, the yellow solid was recrystallized in hexane at −20° C.