Reaktion #74936

Reaktionsgleichung

sodium hydroxide

1,2-diphenyl-4-p-bromophenylbutane-1,4-dione

phosphorus pentasulfide

hydrogen sulfide

hydrogen sulfide

→

2,3-diphenyl-5-p-bromophenylthiophene

Ausbeute 117.1%

Lösungsmittel

ethanol

xylene

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeRecrystallization from 20 ml of dioxane and 60 ml

Vorschrift

A mixture of 31.4 g (0.080 mole) of 1,2-diphenyl-4-p-bromophenylbutane-1,4-dione, 100 ml of xylene, 16 g (0.036 mole) of phosphorus pentasulfide and 125 g (3.67 mole) of hydrogen sulfide was heated in a 1-liter stainless steel autoclave with stirring for four hours at 156°-176° C. (1140-1320 psig). The reactor was cooled to room temperature and the hydrogen sulfide was led into a sodium hydroxide solution. Treatment of the residue with 150 ml of absolute ethanol gave 18.5 g (59.1%) of crude solid, m.p. 135°-137°. Recrystallization from 20 ml of dioxane and 60 ml. of absolute ethanol gave 16.5 g (52.7%) of pure 2,3-diphenyl-5-p-bromophenylthiophene.

Quelle