Sodium Cyanide → 2-Chloro-4-(trifluoromethyl)benzonitrile

Participants

Reaction Conditions

Reaction Steps

A suspension of 10 g of 2-chloro-4-trifluoromethylaniline in 18 g of 95% sulphuric acid and 65 ml of water is slowly added at 15° C. to a solution of 3.57 g of sodium nitrite in 7 ml of water. The reaction mixture is stirred at 40°-45° C. for 2 hours and then carefully poured onto the following mixture maintained at 95° C.: 10.77 g of sodium cyanide, 0.51 g of copper cyanide, 25.8 g of sodium hydrogencarbonate and 0.46 g of nickel sulphate hydrate in 30 ml of water. The reaction mixture is stirred at 100° C. for 1 hour and then, after cooling, 30 ml of a saturated aqueous sodium hydrogencarbonate solution are added and extraction is carried out with dichloromethane. The extract is filtered through celite and then successively washed with water, with salted water, dried over sodium sulphate and evaporated to dryness. The residue is purified on a column of silica gel, eluent: 20/1 (v/v) cyclohexane/ethyl acetate, and 3.55 g of 2-chloro-4-trifluoromethylbenzonitrile are obtained in the form of a brown oil. 1H NMR (CDCl3): 7.4 to 7.8 (m, 3H).

Provenance & Evidence