Croatica Chemica Acta, Vol. 60 No. 2, 1987.
Izvorni znanstveni članak
Kinetic Studies on Base-Catalyzed Condensation of BenzaIdehyde, p-Hydroxybenzaldehyde, p-Dimethylaminobenzaldehyde and N,N-Dimethyl-p-nitrosoaniline with l-Phenyl-3-methyl-2-pyrazolin-5-one
M. M. Girgis
; Chemistry Department, Faculty of Science, Assiut University. Assiut, Egypt
R. M. Hassan
; Chemistry Department, Faculty of Science, Assiut University. Assiut, Egypt
Z. H. Khalil
; Chemistry Department, Faculty of Science, Assiut University. Assiut, Egypt
Sažetak
The condensation reaction of 1-phenyl-3-methyl-2-pyrazolin-5-one (I) with benzaidehyde (II), p-hydroxybenzaldehyde (III),
p-dimethylaminobenzaldehyde (IV) and N,N-dimethyl-p-nitrosoaniline
(V) in ethanolic media containing piperidine as base catalyst was investigated spectrophotometrically at 10-50oC. It was found that these reactions followed over-all second-order kinetics, first-order with respect to each of the reactants. The results suggest that the rate determining step involves the dehydration of the aldol intermediate (XII). From the dependence of the rate constants on temperature, the thermodynamic parameters of activation were determined and the mechanism which is consistent with the obtained data is discussed.
Ključne riječi
Hrčak ID:
176349
URI
Datum izdavanja:
25.6.1987.
Posjeta: 935 *