Oxidation of 3-furfurylcarbinois with bromine in acetone-water

Abstract

Oxidation of 3-furfurylcarbinols 3a-e and 7 with bromine in acetone-water solution gave the 2-substituted-3-furfurals 4a-e and 8 in good yields, respectively. Reaction of 2-alkyl-3-furfurylcarbinols 9a and 9b with bromine in acetone-water gave the bromoalkyl 3-furfuryl ketones 10a and 10b as the major products. A reaction mechanism via the cis-trans isomerization of the 2-ene-1,4-diones 13 and 14 was proposed to account for the transposition of the alkyl group of the 3-furfurylcarbinols 3, 7 and 9 to the 2-position on the furan ring of the products 4, 8 and 10.