The rates of basic methanolysis of some N-Alkyl-p-nitroacetanilides and 4-(N'-Alkylacetamido)pyridines

Abstract

Rate constants for the basic methanolysis of CH₃CONRAr compounds (R=H,Me,Et,Prⁱ; Ar = p-NO₂C₆H₄, 4-pyridyl), and derived activation parameters are reported. There is a close parallel between the effects of the nitro and aza groups on activation energies and entropies foreach R group. The order of reactivity within the R groups is H < Me > Et > Prⁱ. From a consideration of the activation parameters it seems likely that the lower reactivity of the H-compounds is due to the energetically unfavourable breakdown of strongly hydrogen-bonded structures during methanolysis of these compounds.