4,4'-Dihydroxybiphenyl → (1,1'-Bicyclohexyl)-4,4'-diol

Participants

Reaction Steps

In 1 l of isopropanol was dissolved 100 g (0.54 mol) of biphenyl-4,4'-diol, and 5 g of anhydrous sodium carbonate and 5 g of 5% palladium-on-carbon were added to the solution. The mixture was subjected to reduction reaction in an autoclave at 100° C. and at a hydrogen pressure of 5 kg/cm2 for 25 to 30 hours. After completion of the reaction, the reaction mixture was filtered, and the isopropanol was removed from the filtrate by distillation under reduced pressure to recover a part of dicyclohexyl-4,4'-diol. The crystals obtained as a filter cake were dissolved in 500 ml of tetrahydrofuran while hot and filtered. The tetrahydrofuran was removed from the filtrate by distillation under reduced pressure to obtain dicyclohexyl-4,4'-diol. Both crystals were combined, suspended in 1 l of n-hexane while hot, and allowed to stand at 5° to 6° C. for 1 hour. The precipitated crystals were collected by filtration and dried under reduced pressure to obtain 93 g (0.47 mol) of a compound of formula: ##STR28## Melting Point: 179°-181° C.

Provenance & Evidence