Mechanism of Ring Opening Reaction of 4-Benzylidene-2-methyl-5-oxazolone. Part I. Reaction with n-Butylamine

• Autorzy: Betłakowska B. , Banecki B. , Łankiewicz L. , Wiczk W.
• Języki publikacji: EN

Abstrakty

EN

The reaction between 4-benzylidene-2-methyl-5-oxazolone (Ox, c = 5.25 _ 10-5 M) with n-butylamine (nBuA, c = 0.026 to 1.66 M) in acetonitrile was studied by UV-Vis spectroscopy using steady-state and stopped-flow apparatus. The amine to Ox molar ratio higher than 500 allows to apply pseudo-first order approximation, whose rate constants depend on amine concentration according to a parabolic equation: kobs = 4.63 _ 0.02 _ CnBuA 2 , indicating a complex reaction mechanism. On the other hand, singular value decomposition (SVD) analysis, as well as global analysis of the data obtained from stopped-flow measurements support a simple A B reaction model. Nonlinear dependence of the pseudo- first order rate constant on amine concentration can be explained, assuming that the oxazolone ring opening reaction by n-butylamine in acetonitrile proceeds as parallel reactions: A + B C and A+2B C. Based on our experimental results and theoretical calculations of the oxazolone ring opening reaction, a mechanism of the reaction between 4-benzylidene-2-methyl-5-oxazolone and n-butylamine is proposed.

Słowa kluczowe

EN

4-benzylidene-2-methyl-5-oxazolone; n-butylamine; stopped-flow; reaction mechanism; dehydropeptides; kinetics; activation parameters

• Wydawca: Polskie Towarzystwo Chemiczne
• Czasopismo: Polish Journal of Chemistry
• Rocznik: 2001
• Tom: Vol. 75, nr 3
• Strony: 401--410
• Opis fizyczny: Bibliogr. 22 poz., rys.

Twórcy

autor

Betłakowska B.

• Faculty of Chemistry, University of Gdańsk, Sobieskiego 18, 80-952 Gdańsk, Poland

autor

Banecki B.

• Intercollegiate Faculty of Biotechnology, University of Gdańsk & Medical Academy of Gdańsk, Kładki 24. 80-822 Gdańsk, Poland

autor

Łankiewicz L.

• Faculty of Chemistry, University of Gdańsk, Sobieskiego 18, 80-952 Gdańsk, Poland

autor

Wiczk W.

• Faculty of Chemistry, University of Gdańsk, Sobieskiego 18, 80-952 Gdańsk, Poland

Bibliografia

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