Preparation and Route of Asterriquinone Monoalkyl Ether from Asterriquinone Diacetate by Treatment with a Mixture of Alcohol and Alkali, Followed by Acidification.

Abstract

3-Alkoxy-6-hydroxy-p-benzoquinones were prepared by the treatment of 3, 6-diacetoxy-p-benzoquinones with a mixture of alcohol and alkali, followed by acidification. The key intermediate acetoxy-alkoxy-p-benzoquinones were formed by the base-catalyzed addition of an alkoxy anion to the conjugated double bonds in the diacetoxy-p-benzoquinone ring, followed by an acetoxy anion elimination. This method was applied for preparing a novel o-quinone derivative of asterriquinone (ARQ) by the addition of 2-haloethanol and intramolecular O-alkylation.