Hydrogen Bromide → 3'-Bromo-6,2',6'-trifluorobiphenyl-2-carbonitrile

Participants

Reaction Conditions

Reaction Steps

To a solution of 3′-amino-6,2′,6′-trifluorobiphenyl-2-carbonitrile (0.5136 g, 2.07 mmol) in hot 1,4dioxane (1 ml) was added 48% aqueous hydrobromic acid (7 ml) and the mixture was cooled to −5° C. before adding dropwise a solution of sodium nitrite (0.1657 g, 2.40 mmol) in water (0.5 ml) over 5 min so that the temperature did not rise above −4° C. The resulting mixture was stirred at −5 to 2° C. for 2 h before adding a cooled (5° C.) solution of copper(I) bromide (0.4452 g, 3.10 mmol) in 48% hydrobromic acid (3 ml). The mixture was stirred for 5 min then heated to 46° C. over 1 h. The mixture was cooled to ambient temperature, diluted with water (50 ml) and extracted with diethyl ether (2×30 ml). The combined organic extracts were washed with 10% aqueous ammonia (25 ml), then saturated aqueous NaCl (20 ml), dried (MgSO4), and evaporated in vacuo. Purification by chromatography (silica gel, 20% EtOAc/isohexane) gave 0.3790 g (59%) of 3′-bromo-6,2′,6′-trifluorobiphenyl-2-carbonitrile as a white solid.

Provenance & Evidence