Acid catalysed hydrolysis of substituted acetanilides. Part II

Abstract

The rate constants of hydrolysis of 12 para-substituted acetanilides have been measured in 5–98%(w/w) H₂SO₄ at 100.1°. In H₂SO₄( < 65% w/w) the data are reasonably well fitted by the Yates r and Bunnett-Olsen criteria for an A-2 mechanism, and correlate well with Hammett σ. Acetanilides with electron-donating substituents in the 4-position, i.e. OH, Me, MeO, and EtO are sulphonated in >70%(w/w) H₂SO₄ and these substituted intermediates and the other acetanilides studied are hydrolysed in concentrated (>70% w/w) H₂SO₄ by an A-1 mechanism.