Trichloroacetyl chloride → (4-Trichloroacetoxyimino-cyclohexa-2,5-dienylidene)-phenyl-acetonitrile

Participants

Reaction Conditions

Reaction Steps

8 g (36 mmol) of (4-Hydroxyimino-cyclohexa-2,5-dienylidene)-phenyl-acetonitrile, prepared as described in example 1.1, are dissolved in 90 ml of tetrahydrofuran (THF) and cooled in an ice bath. After adding 7.2 g (39 mmol) of trichloroacetyl chloride to the solution, 5.4 g (54 mmol) of triethylamine are added dropwise, keeping the temperature below 5° C. While the reaction mixture is stirred at 5° C. for 50 min, a precipitate is formed. The precipitate is filtered off and washed with THF. The filtrate is concentrated by a rotary evaporator. The residue is diluted with 2-propanol (2-PrOH) and stirred at room temperature overnight. After cooling the mixture in an ice bath, the solid is isolated by filtration and washed with 2-PrOH. The product is obtained in the form of an orange solid,mp 147-148° C.(Dec). The structure is confirmed by the 1H-NMR spectrum (CDCl3). δ [ppm]: 6.97 (dd, 1H), 7.30 (dd, 1H), 7.38 (dd, 1H), 7.52 (s, 5H), 7.65 (dd, 1H). 1H-NMR reveals the presence of a single isomer.

Provenance & Evidence