Sodium Hydroxide → 4-Isocyanato-2-(trifluoromethyl)benzonitrile

Participants

Reaction Conditions

Reaction Steps

21.16 g of triphosgene are dissolved in 100 mL of anhydrous toluene in a 500 mL four-neck bottle equipped with a nitrogen intake, a magnetic stirrer, a condenser and a guard filled with 2 N sodium hydroxide. A solution of 20 g of 4-amino-2-trifluoromethylbenzonitrile in 125 mL of anhydrous dioxan is added dropwise at ambient temperature in 1 hour 30 min. The mixture is heated to 110° C. Pronounced release of gas for 1 hour then appearance of an insoluble brown substance. After 2 hours under reflux, stirring is maintained overnight at AT. The insoluble matter is filtered and rinsed with toluene. The filtrate is concentrated in order to obtain 21.8 g of expected product (Yd=96%). The product is stored in solution in THF (2 M) in a refrigerator.

Provenance & Evidence