Carbazole → 9-(4-Bromophenyl)carbazole

Participants

Reaction Conditions

Reaction Steps

Into a 300 mL three-neck flask were put 56 g (240 mmol) of p-dibromobenzene, 31 g (180 mmol) of 9H-carbazole, 4.6 g (24 mmol) of copper(I) iodide, 66 g (480 mmol) of potassium carbonate, and 2.1 g (8 mmol) of 18-crown-6-ether. Then, the atmosphere in the flask was replaced with nitrogen. Then, 8 mL of N,N′-dimethylpropyleneurea (abbreviation: DMPU) was added to the mixture, and the mixture was stirred at 180° C. for 6 hours. After the reaction mixture was cooled to room temperature, a precipitate was removed by suction filtration. The filtrate was washed with dilute hydrochloric acid, a saturated aqueous sodium hydrogen carbonate solution, and a saturated saline solution in that order, and dried with magnesium sulfate. After being dried, the mixture was gravity filtered and then concentrated to give an oily substance. The obtained oily substance was purified by silica gel column chromatography (hexane:ethyl acetate=9:1) and recrystallized with chloroform and hexane, whereby 21 g of light-brown plate-shaped crystals of 9-(4-bromophenyl)-9H-carbazole which was the object of the synthesis was obtained in a yield of 35% (synthesis scheme (a-5)).

Provenance & Evidence