Hydrochloric Acid → HCID 20161367, compound

Participants

Reaction Steps

A suspension of 5-[N-(2-propenyl)-2-oxo-3-pyrrolin-4-yl]amino-1-(2-chloroethyl)-4-cyanopyrazole (19.60 g.) in dry dichloromethane (200 ml.) was cooled to 0° under nitrogen with stirring, while a solution of trimethylaluminium in hexane (57 ml. of 25 wt. % solution) was added dropwise. Gas evolved. The resulting clear yellow solution was warmed to room temperature and allowed to stir under nitrogen for three days. After cooling to 0° and introducing a vigorous stream of nitrogen, 3N aqueous HCl was added cautiously until gas evolution ceased. The mixture was then diluted with aqueous NaOH (400 ml. of 20% w/v solution) and dichloromethane (500 ml.) and the phases were separated. The aqueous layer was further extracted twice with dichloromethane (250 ml. each time) and the organic extracts were combined. These were washed with aqueous NaOH (250 ml. of 10% w/v solution), and then with brine (400 ml.), and finally dried (Na2SO4) Evaporation gave a yellow solid which was recrystallized from a minimum of EtOAc to give 4-amino-1-(2-chloroethyl)-6,7-dihydro-6-(2-propenyl)pyrazolo[3,4-b]pyrrolo[3,4-e]pyridin-5(1H)-one as a light yellow powder, 15.71 g.: m.p. 197.5°-199°.

Provenance & Evidence