Substitution Reactions of Nitrothiophens. II. The Anomalous Reaction of 4-Nitro-2-thenylidene Diacetate with the 2-Nitropropan-2-ide Ion

Abstract

The reaction of 4-nitro-2-thenylidene diacetate with 2-nitropropan-2-ide ion gives rise to 4-nitro-2-thenaldehyde (6), which is converted into its Meisenheimer adduct (13), together with small amounts of 2-(2'-methylprop-1'-enyl)-4-nitrothiophen (a), 5-(1'-methyl-1'-nitroethyl)-2-(2-methylprop-1''-enyl)-4-nitrothiophen (9) and 2-methyl-1-[5'-(1''-methyl-1''-nitroethyl)-4'-nitro-2'-thienyl]-2-nitro- propyl acetate (10). Mechanistic routes relating the adduct (13), whose ¹H and ¹³C N.M.R. data are presented, and the two other proposed intermediates, 5-(1'-methyl-1'-nitroethyl)-4-nitro-2-thenalde- hyde (11) and 2-methyl-2-nitro-1-(4'-nitro-2'-thienyl)propyl acetate (12), are discussed.