Reaction of 2,4,6-Tri-t-butylnitrobenzene with Alky Grignard Reagents

Reactions of 2,4,6-tri-t-butylnitrobenzene (1) with alkylmagnesium halides afforded 2,4,6-tri-t-butylaniline (2), N-alkyl-2,4,6-tri-t-butylanilines (3), 6-alkyl-2,4-di-t-butylanilines (4), 4-alkyl-1-hydroxyimino-2,4,6-tri-t-butyl 2,5-cyclohexadienes (5), and 6-alkyl-1-hydroxyimino-2,4,6-tri-t-butyl-2,4-cyclohexadienes (6) depending on the Grignard reagents used. Reduction of the oxime 6 proved to be responsible for the formation of the aniline 4. Comparison of the present reactions with those of 2,4,6-tri-t-butylnitrosobenzene (7) with Grignard reagent, syn-anti-isomzrs of the oxime 6, and the formation mechanisms of the products have been discussed.