Hydrochloric Acid → 1,8-Dichloro-10-[Bis(Ethoxycarbonyl)Methylene]-Anthrone

Participants

Reaction Steps

In a 250 milliliter round-bottomed flask equipped with a pressure equalizing dropping funnel, there was discharged 10 grams of 1,8-dichloroanthraquinone, 16.5 milliliters of diethyl malonate, and 150 milliliters of methylene chloride under a nitrogen atmosphere. The resulting mixture was then mechanically stirred and cooled with an ice bath. Thereafter, 24 milliliters of titanium tetrachloride was added dropwise through the dropping funnel over a period of 20 minutes, followed by the addition of 45 milliliters of pyridine. The reaction mixture was then stirred at room temperature for 65 hours. Subsequently, 150 milliliters of a dilute aqueous hydrochloric acid solution was slowly added with stirring. The organic phase resulting was separated, washed twice with water, and dried with anhydrous magnesium sulfate. Evaporation of the dried organic solution yielded a yellowish solid which when recrystallized from methanol afforded 7.5 grams of the pure Compound (VIII), mp., 166°-167° C.

Provenance & Evidence