Hydrogen Sulfide → 2,3-Diphenyl-5-p-fluorophenylthiophene

Participants

Reaction Conditions

Reaction Steps

A mixture 49.8 g (0.15 mole) of 1,2-diphenyl-4-p-fluorophenylbutane-1,4-dione, 100 ml of xylene, 30 g (0.0675 mole) of phosphorus pentasulfide and 130 g (3.81 moles) of hydrogen sulfide was heated and stirred in a 1-liter stainless steel autoclave for 4 hours at 157°-185° C. (620-1145 psig). After cooling the vessel to 20° C. and venting the hydrogen sulfide into a sodium hydroxide solution, the residue was stirred with 150 ml of absolute ethanol. Filtration gave 31.5 g (63.6%) of crude product, m.p. 108°-110° C. Recrystallization from 30 ml of dioxane and 90 ml of ethanol gave 24 g of pure 2,3-diphenyl-5-p-fluorophenylthiophene, m.p. 111°-113° C.

Provenance & Evidence