Molecular complexes of phenols with DDQ

Molecular complexes of phenols with DDQ have been studied spectrophotometrically in the temperature range of 10–30C in a solvent (CHCl3) of low polarity under low donor concentrations. All the complexes exhibit one CT band each in the wavelength region where acceptor and donor do not have any absorption. The complexes are inferred to be of the p–p type and have Ry configuration in which the donor molecular orbital encompasses the substituent. The ionization potentials of the donors, the stability constants and thermodynamic parameters of the complexes have been evaluated.