CATALYSIS OF THE CIS - TRANS ISOMERIZATION OF AZOBENZENE BY ACIDS AND CUPRIC SALTS
1959; NRC Research Press; Volume: 37; Issue: 11 Linguagem: Inglês
10.1139/v59-278
ISSN1480-3291
AutoresStefania Ciccone, Joshua B. Halpern,
Tópico(s)Advanced Physical and Chemical Molecular Interactions
ResumoThe catalytic effects of various acids and metal salts on the cis-trans isomerization of azobenzene in aqueous ethanol were examined kinetically. The effect of perchloric acid is apparently due to H + ions and is interpreted in terms of a catalytic mechanism involving the conjugate acid of azobenzene. The much greater catalytic effect found for hydrochloric acid is attributed to an additional path involving catalysis by the undissociated acid. Acetic acid was found to be inactive. Of the metal salts examined only those of Cu ++ showed pronounced activity which was attributed to co-ordination with the azo group. Kinetic evidence was obtained for a catalytic path involving Cu ++ and H + simultaneously.
Referência(s)