1,2-Dibromoethane → 9,9-Bis(3-bromophenyl)-9H-fluorene

Participants

Reaction Steps

62.9 g (270 mmol) of 2-bromobiphenyl mixed with 400 ml of THF, 550 ml of toluene, 45 ml of 1,2-dimethoxyethane and 2.6 ml of 1,2-dibromoethane are reacted with 6.6 g (250 mmol) of magnesium to give the corresponding Grignard compound. A solution of 60.0 g (176 mmol) of bis(3-bromophenyl) ketone in 600 ml of THF is added dropwise to the cooled Grignard solution. When the addition is complete, the reaction mixture is heated under reflux for 4 h, the solvent is then removed in vacuo, the residue is dissolved in 700 ml of glacial acetic acid, 10 ml of hydrogen bromide in 30% glacial acetic acid are added, and the mixture is heated under reflux for 6 h. After cooling with stirring, the precipitated solid is filtered off with suction, washed twice with 200 ml of glacial acetic acid each time and three times with 300 ml of ethanol each time and then dried in vacuo. Yield: 69.0 g (145 mmol), 82.1%, 99% pure according to 1H-NMR.

Provenance & Evidence