Nuclear magnetic resonance investigations of carbonium ion intermediates. Part II. Exchange reactions in chloro-iminium salts (Vilsmeier–Haack reagents)

Abstract

Different kinds of coalescence phenomena have been observed for solutions of chloro-iminium salts. The rate of the exchange mechanism is concentration dependent. An acid–base equilibrium between the Vilsmeier complex (Me₂NCHCl)⁺B^– and the dimethylformamide is evident. Thermodynamic and kinetic parameters have been calculated for different solvents and different anions B^– by total line shape analysis of continuous wave and Fourier transform spectra.