Synthesis of Ethyl Acetohydroximate and Derivatives from Imidate Hydrochloride.

An efficient synthesis of ethyl acetohydroximate (EAH) and derivatives was developed. EAH was synthesized from ethyl acetimidate hydrochloride, which was prepared from acetonitrile and ethanol in the presence of acetyl chloride, with hydroxylamine and potassium carbonate. A series of reactions were performed to prepare imidate hydrochloride without direct use of hydrogen chloride gas and yielded more than 10 g of EAH without the need for chromatography. This method allows the synthesis of EAH derivatives from various alcohols and nitriles under the same conditions. In addition, the EAH derivatives obtained were converted into benzenesulfonylated oximes, which were evaluated for reactivity in the Beckmann rearrangement.