The formylation of ketones

Abstract
Formylation of ketones with carbon monoxide to give α‐formyl ketones under the influence of alkali metal alkoxides in dimethoxyethane (DME) can occur in two ways. With primary alkoxides as bases, formylation takes place via alkyl formates. Addition of the corresponding alcohol favors the reaction. When potassium tert‐butoxide is used, besides this indirect reaction, a direct reaction of the ketone anion with CO occurs. In the absence of alcohols e.g. when the ketone is ionized by potassium naphthalene only the direct reaction occurs; its mechanism has been studied in more detail.