| Abstract: | An investigation has been made by the CNDO/S method with allowance for configurational interaction (the lowest six vacant and the highest eight occupied MMOs) of the electronic structure of a number of quinones and quinone methides forming component parts of the structural unit of lignin. The energies of the first singlet-singlet and singlet-triplet transitions and the redistribution of charges on excitation have been obtained, and the dependence of the energy of the transitions on the chromophores present in the molecule has been discussed. The change in the donor-acceptor properties of the fragments in excited states, leading to a change in the pathways in nucleophilic and electrophilic reactions has been shown.A. A. Zhdanov Irkutsk State University. Translated from Khimiya Prirodynkh Soedinenii, No. 6, pp. 858–865, November–December, 1988. |
