Boron tribromide → 4-Hydroxy-p-quaterphenyl

Participants

Reaction Steps

First, 25.2 g (75 mmol) of MQ obtained in section (L) mentioned above was suspended to 500 ml of methylene chloride in an 1-liter three-necked flask. To this suspension, 50 ml of a methylene chloride solution containing 19.0 g (75 mmol) of boron tribromide was added dropwise over a period of about 30 minutes with stirring under a nitrogen atmosphere. Then, the reaction mixture was refluxed for 10 hours with stirring under the nitrogen atmosphere. After the reaction was completed, the flask was cooled, and the solids that precipitated were obtained by filtration. The solids were washed with methylene chloride and dried. Then the solid was recrystallized with dimethylsulfoxide. In this way, 21.6 g (yield, 89%) of 4-hydroxy-p-quaterphenyl (HQ) was obtained as a white solid. The liquid-crystal transition temperature of HQ was 352° C.

Provenance & Evidence