The Hoffmann-Schiff dichotomy: on the reaction between chloral and amines

Abstract

In the nearly two centuries since the discovery of chloral (2,2,2-trichloroacetaldehyde), numerous nitrogenous reactants have been used to generate products resulting from attack at the carbonyl group by nitrogen. The resulting tetrahedral species, a carbinolamine, is often unstable and has been reported to lose water to produce an imine as well as to lose chloroform to produce an amide. We find that the path, and hence the product, is a function of the electron density at the nitrogen of the reacting amine. The weaker arylamines produce imine whilst the more strongly basic alkylamines produce amide.