Tetrahydrofuran → 2,3-Dioxoindoline-5-carbonitrile

Participants

Reaction Steps

According to the general procedure, using an equimolar amount of potassium t-butoxide, 0.62 g of 5-cyano-3-methylthiooxindole in 200 ml of dry tetrahydrofuran was stirred and aerated for 9 h at 0° C. and 15 h at 25° C. Acidification with 0.25 ml of conc. hydrochloric acid in 25 ml of water, followed by extraction with ether and standard workup (vide supra), gave an orange solid. Recrystallization from 95% ethanol gave 0.18 g (35% yield) of 5-cyanoisatin, mp 273°-274° C. (dec.).

Provenance & Evidence