Collect. Czech. Chem. Commun. 1984, 49, 2807-2815

Kinetic analysis of reactions of phenylhydrazonopropanedinitriles with thiols

Marián Antalíka, Ernest Šturdíka, Oldřich Pytelab, Ľudovít Drobnicaa and Pavol Suloa

a Department of Technical Microbiology and Biochemistry, Faculty of Chemical Technology, Slovak Institute of Technology, 812 37 Bratislava
b Department of Organic Chemistry, Institute of Chemical Technology, 532 10 Pardubice


Phenylhydrazonopropanedinitriles react with aliphatic thiols in aqueous solutions to give 2-phenylhydrazono-3-imino-3-alkylthiopropanedinitriles. The observed first-order rate constants kobs (s-1) depend on pH value of the reaction medium and on the thiol concentration. Kinetic analysis showed that the reactions are nucleophilic additions of bimolecular type involving non-dissociated phenylhydrazonopropanedinitriles and thiolate anions as the electrophilic and nucleophilic partners, respectively. A relation is given enabling transformation of the found kobs constants into the second-order rate constants k (1 mol-1 s-1) independent on the pH value of medium and of the thiol concentration.