The Pfitzinger2 method of synthesis of substituted cinchoninic acids, like cinchophen, from isatin and methyl ketones with concentrated potash, serves as a convenient reaction when no alkali-sensitive groups are present. The desirability of a more gentle method suggested the Knoevenagel8 catalysts in place of the alkali.When an alcoholic solution of isatin and acetophenone containing a small quantity of diethylamine is allowed to stand overnight a copious yield of a product (I) is obtained. The product is not cinchophen but is, according to its empirical formula, an addition product C8H502N
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.