Effect of Partially Aqueous Solutions of Different pH's on the Hydrolisis Rate of Some Schiff Bases

• Autorzy: El-Taher M. , El-Haty M. T. , Hussien T. M.
• Języki publikacji: EN

Abstrakty

EN

The mechanism of the hydrolysis of a series of Schiff bases derived from p-phenylenediamine and various aromatic aldehydes has been examined in aqueous media containing 40 wt% methanol, in the presence of NaOH. The base hydrolysis reaction of these compounds is strictly second-order kinetics, first-order with respect to the Schiff base and also to hydroxide ion, and the hydroxide ion attack on the free base becomes the rate-determining step under these basic conditions. The work is extended to include a systematic kinetic study on the hydrolysis reaction of the Schiff bases under investigation, in partially aqueous solutions of different pH's, in media containing 40 wt% methanol. Arate profile diagram of pH versus hydrolysis rate constant for all of the Schiff bases shows that the rate is minimal at alkaline region (pH > 8.96), and too rapid at strongly acidic media (pH < 3.53).

Słowa kluczowe

EN

Schiff bases; kinetics; base hydrolysis

• Wydawca: Polskie Towarzystwo Chemiczne
• Czasopismo: Polish Journal of Chemistry
• Rocznik: 2001
• Tom: Vol. 75, nr 1
• Strony: 79--91
• Opis fizyczny: Bibliogr. 28 poz., rys.

Twórcy

autor

El-Taher M.

• Chemistry Department, Faculty of Science, Aswan, Egypt

autor

El-Haty M. T.

• Chemistry Department, Faculty of Science, Aswan, Egypt

autor

Hussien T. M.

• Chemistry Department, Faculty of Science, Aswan, Egypt

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