Preparation of and addition of carbanions to 6-methyl-6-nitrocyclohexa-2,4-dienones

Abstract

Nitration of 2-methylphenols with nitric acid and trifluoroacetic anhydride in ether at −78 °C gives 6-methyl-6-nitrocyclo-hexa-2,4-dienones that can be isolated. Carbanions add to 5,6-dimethyl-6-nitrocyclohexa-2,4-dienone to give the 5-substituted 2,3-dimethyl-2-nitrocyclohex-3-enone anion, which, with additional carbanion, gives the 5-substituted 2,3-dimethylphenoxide anion by elimination of nitrous acid. Keywords: nitration, dienone, addition, carbanion, nucleophilic.