1,4-Dibromobenzene → 3,3'-(1,4-Phenylene)di(prop-2-yn-1-ol)

Participants

Reaction Steps

A solution of 1,4-dibromobenzene (1.18 g, 5.0 mmol) in n-propylamine (15 ml) is admixed successively with Pd(Ph3P)4 (116 mg, 2%), CuI (28 mg, 3%) and propargyl alcohol (0.9 ml, 15 mmol) and stirred at RT for 1 h and then at reflux for 7 h. More Pd(Ph3P)4 (58 mg, 1%), CuI (14 mg, 1.5%) and propargyl alcohol (0.45 ml, 7.5 mmol) are then added, and the mixture is stirred at reflux for a further 8 h. After cooling, the reaction mixture is filtered off with suction over kieselguhr and the filter cake is washed with ethyl acetate (20 ml). The organic phase is concentrated under reduced pressure. Further purification is carried out by chromatography [Tol/Ac (8:2)] over a silica gel column. This gives the title compound (0.84 g) as a colorless solid. TLC, silica gel (glass plates), [toluene/acetone (8:2)], Rf=0.22.

Provenance & Evidence