Charge transfer complexes of iodine with mercaptans and related sulphur compounds

Abstract

Charge transfer complexes of iodine (σ acceptor) with ethyl and phenyl mercaptan, and diphenyl sulphide and disulphide (n-donors) have been studied in cyclohexane at 25°C. Spectral data, stability constants, enthalpies and entropies of complexation are reported. As comparison with literature data for related compounds, the stability of the complexes is correlated with the donor structure and discussed in terms of electronic and steric factors. The effect of substituents on K_ct of thiophenols has been investigated leading to an Hammett reaction constant of –1.11.