Unexpected nuclear formylation and acetylation of some nitroanilines with dimethyl sulfoxide in the presence of a strong base

When treated with a strong base such as KOtBu or NaH in dimethyl sulfoxide at room temperature, 2,4-dinitro-, 2-cyano-4-nitro- and 4-cyano-2-nitroanilines were found to undergo regiospecific acylation at the 3-position to afford the corresponding 3-formyl or 3-acetyl derivatives in fair to moderate yields.