The Reaction of 7, 7'-Diacetoxy-4, 4'-dimethyi-3,4-dihydro-4, 6'-bicoumarin with Aluminum Chloride

Abstract

It has previously been reported that 7, 7'-dihydroxy-4, 4'-dimethyl-3, 4-dihydro-4, 6'-bicou-marin [4] was obtained from the reaction of resorcinol [1] with methyl acetoacetate [2]. The reaction of [5], diacetate of [4], with aluminum chloride has now been studied. The products were found to be 2, 4-diacetylresorcinol [6], 4, 6-diacetylresorcinol [7], 2, 4, 6-triacetylresorcinol [8] and 4, 6-dimethyl-2 H, 8 H-benzo [1, 2-b: 5, 4-b'] dipyran-2, 8-dione [9] mainly on the spectroscopic evidence. Expected Fries reaction products of [5] were not obtained. Tne plausible mechanism for the formation of [6]~[9] ls discussed briefly (Scheme 3). © 1985, The Chemical Society of Japan. All rights reserved.