ELECTROCHEMICAL STUDY OF INTRAMOLECULAR CHARGE-TRANSFER COMPLEXES DERIVED FROM 1,4-NAPHTHOQUINONE .1. ELECTROREDUCTION

Electrochemical investigations (polarography, cyclic voltammetry, rota ting ring-disk electrode voltammetry) of intramolecular charge transfe r complexes (AC) derived from 1,4-naphthoquinone were performed in ace tonitrile. It is concluded that in the first one-electron stage of its electrochemical reduction the AC is in a complexed form. At the same time the amino moiety, which shows a marked inductive (-I) effect, act s as an electron donor in the donor-acceptor (D-A) interaction. Facili tation of the reduction of the quinone part by the aryl amine residue is compensated by the D-A interaction, which makes the electroreductio n more difficult. By using ultramicroelectrodes it was shown that the primary reaction products (naphthosemiquinone anions) easily form ion pairs with the tetrabutylammonium ion (TBA(+)).