Acetic Acid → HCID 14204091, compound

Participants

Reaction Steps

Into a 1-liter, three-necked flask equipped with a gas dispersion tube, reflux condenser, rubber septum and nitrogen inlet is placed 7 g (0.04 mole) of 5-nitro-1-cyanobenzocyclobutene and 400 ml of absolute 2B ethanol. The mixture is stirred under nitrogen and heat is applied to dissolve the solid. After adding 2.4 ml of glacial acetic acid and 1.6 g of 5 percent palladium on carbon, hydrogen flow is initiated and the mixture is hydrogenated at atmospheric pressure and ambient temperature. The hydrogenation is followed by thin-layer chromatography (silica gel; 70 percent toluene, 25 percent ethyl acetate, 5 percent triethylamine as eluent) and this shows the reaction is essentially complete in 1 hour. After 3 hours, the hydrogen flow is stopped and the system is purged with nitrogen for 15 minutes to remove excess hydrogen gas. The catalyst is removed by filtration using Celite and quickly quenched in water. The filtrate is evaporated to dryness on a rotary evaporator and the residue is treated with aqueous 10 percent sodium hydroxide. The aqueous solution is extracted with three 100-ml portions of ethyl ether, and the solutions are combined and washed once with 100 ml of water. The ethyl ether solution is dried over anhydrous potassium carbonate, filtered and evaporated on a rotary evaporator to give an amber-colored oil that solidified on standing. The product is pumped under vacuum overnight to remove the last traces of ethyl ether and stored under nitrogen. The infrared, 'H and 13C nuclear magnetic resonance are run. The yield is 86.4 percent.

Provenance & Evidence