Nitration of 2,3,4,6-Tetramethylphenol and 1,2,3,5-Tetramethylbenzene

Abstract

Nitration of 1,2,3,5-tetramethylbenzene (2a) with fuming nitric acid gives the tetramethylnitrobenzene (22), products of side-chain modification (23)-(27), the rearranged 6,6-dimethylcyclohexenones (8), (28), (29) and (30), and 2,3,4,6-tetramethyl ketone derivatives (10)- (13), (31) and (32). Reaction of 2,3,4,6-tetramethylphenol (7) with nitrogen dioxide gives the hydroxy dinitro ketone (9) in addition to the trinitrocyclohexenones (11)-(14) and (19). X-ray crystal structures are reported for compounds (11), (19), (28), (29), (30) and (32). ¹H n.m.r ./stereochemistry correlations are reported for some 2,5-dinitro- and 2,5,6-trinitro-cyclohex-3-enones.