Related Products of 108-47-4, Chemistry is the science of change. But why do chemical reactions take place? Why do chemicals react with each other? The answer is in thermodynamics and kinetics.In a document type is Article, and a compound is mentioned, 108-47-4, 2,4-Dimethylpyridine, introducing its new discovery.
Kinetics and Mechanisms of Reactions of Pyridines and Imidazoles with Phenyl Acetates and Trifluoroacetates in Aqueous Acetonitrile with Low Content of Water: Nucleophilic and General Base Catalysis in Ester Hydrolysis
Reactions of pyridines and imidazoles with substituted phenyl acetates and trifluoroacetates have been studied in acetonitrile and in water-acetonitrile containing 0.56 mol/dm3 of water.The water isotope effects, steric effects, the effect of water in the reaction medium, and the derived Broensted beta and Hammett rho values have been used as mechanistic criteria.Pyridines and imidazoles catalyse the hydrolysis of phenyl trifluoroacetates by general base catalysis while imidazole acts as nucleophile toward 4-nitrophenyl and 2,4-dinitrophenyl acetates.As indicated by the second-order dependence on amine concentration beside the first-order term in amine, the reaction of imidazole exhibits general base catalysis in the case of both phenyl acetates and phenyl trifluoroacetates.This reaction obviously is general base-catalysed nucleophilic reaction of imidazole.The activation parameters DeltaH* and DeltaS* derived for the reactions of pyridine and imidazole with 4-nitrophenyl trifluoroacetate and for the reaction of imidazole with 4-nitrophenyl acetate are consistent with the proposed reaction mechanisms.
Balanced chemical reaction does not necessarily reveal either the individual elementary reactions by which a reaction occurs or its rate law.Related Products of 108-47-4. In my other articles, you can also check out more blogs about 108-47-4
Reference£º
Chiral nitrogen ligands in late transition metal-catalysed asymmetric synthesis¡ªI. Addressing the problem of ligand lability in rhodium-catalysed hydrosilations,
Nitrogen-Containing Ligands for Asymmetric Homogeneous and Heterogeneous Catalysis