The kinetics and mechanism of polymer-based NHC-Pd-pyridine catalyzed heterogeneous Suzuki reaction in aqueous media
Küçük Resim Yok
Tarih
2019
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Wiley
Erişim Hakkı
info:eu-repo/semantics/closedAccess
Özet
One of the most important challenges of the Suzuki reaction is a green synthesis of reaction products. In terms of economy and ecology, the Suzuki reaction details must be characterized for the industrial-scale Suzuki reaction processes. In this paper, for the first time, a kinetic and mechanistic study on the Suzuki reaction catalyzed with hydrogel-supported PEPPSI (pyridine-enhanced precatalyst preparation stabilization (and) initiation) type NHC-Pd-pyridine composite has been investigated. To determine the rate-limiting step, the effects of reactants and experimental conditions on the heterogeneous Suzuki reaction have been experimentally defined. The experimental results demonstrated that it is possible to reach 100% yield under the optimum reaction conditions, which were found as 75 x 10(-3) mol/L of phenylboronic acid (FBA), 50 x 10(-3) mol/L of bromoacetophenone (Brac), 125 x 10(-3) mol/L of K2CO3, 1 g/L of catalyst, 80 degrees C of reaction temperature, 400 rpm of mixing rate, and 3 h of reaction time. The transmetalation step in the cycle was defined as the rate-limiting step. On the basis of kinetic results, a mathematical reaction rate expression was presented assuming the steady-state approach to steps of the catalytic cycle. The activation energy (E-a) of the reaction was estimated to be 34.88 kJ/mol.
Açıklama
Anahtar Kelimeler
heterogeneous catalysts, reaction kinetics, reaction mechanisms, Suzuki reactions
Kaynak
International Journal of Chemical Kinetics
WoS Q Değeri
Q4
Scopus Q Değeri
Q3
Cilt
51
Sayı
12
