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A number of diacetanilides, including some which have not been reported so far, have been synthesized from the corresponding monoacetyl derivatives and characterized by spectral and elemental analyses. A tlc/fid method for the quantitative estimation of the relative amounts of mono- and diacetyl derivatives has been standardized. Linear correlation of the extent of diacetylation with Hammett σ-values of substituents and basicity constants of monoacetyl derivatives has been established. A plausible mechanism for the diacetylation reaction based on experimental observations has been suggested. An explanation for the anomalous behaviour of acetanilides containing electron-withdrawing substituents in the ortho position has been put forth.

Dinitroarenes containing substituents such as hydroxyl and amine groups could be conveniently reduced with 3 molar equivalents of hydrazine hydrate in presence of Raney nickel catalyst in ethanol/1,2-dichloroethane solvent mixture to give a product wherein one of the two nitro groups was reduced to the amino group. The yields of the partial reduction products are good. Under similar conditions alkoxyl substituents in the o,p-position to the nitro groups were displaced by the hydrazino group to give 2,4-dinitrophenylhydrazine as the main product. The details of the reduction reaction are described.