Kinetics and Mechanism of the Nucleophilic Cleavage of Disulfide Bond in 2,2-Dithio-diimidazoles with Hydroxide Ions

• Autorzy: Kurzawa J. , Suszka A.
• Języki publikacji: EN

Abstrakty

EN

Kinetics of the cleavage of disulfide bond of dithiobisdisulfides of diimidazoles to their parent imidazoles by hydroxide ion have been investigated spectrophotometrically. Rate equation and other observations suggest that the nucleophilic attack of hydroxide ion on one of the sulfur atoms of disulfide bond is a rate limiting step. This process is accompanied by much slower, parallel reaction with water as a nucleophile. Hence the full kinetic equation for nucleophilic cleavage of 2,2 -dithio-diimidazoles in aqueous alkaline solutions is a two-term equation: –(d[RSSR]/dt) = k1[RSSR][OH–] + k2[RSSR][H2O], where k1 > k2. The mechanism of the reaction is proposed.

Słowa kluczowe

EN

dithio-diimidazoles; nucleophilic cleavage; hydroxide ion; reaction mechanism

• Wydawca: Polskie Towarzystwo Chemiczne
• Czasopismo: Polish Journal of Chemistry
• Rocznik: 2007
• Tom: Vol. 81, nr 8
• Strony: 1487--1494
• Opis fizyczny: Bibliogr. 11 poz., rys.

Twórcy

autor

Kurzawa J.

autor

Suszka A.

• Institute of Chemistry, Poznań University of Technology, Piotrowo 3, 60–965 Poznań, Poland,

Bibliografia

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