Substrate specificity in the biomimetic catalytic aerobic oxidation of styrene and cyclohexanone by metalloporphyrins: kinetics and mechanistic study

Substrate specificity is a hallmark of enzymatic catalysis. In this work, the biomimetic catalytic oxidation of styrene and cyclohexanone by iron (III) porphyrins and molecular oxygen was carried out, and remarkable differences in efficiency were observed. The specificity of the substrates for biomi...

Full description

Bibliographic Details
Main Authors: Xian-Tai Zhou, Hong-Bing Ji
Format: Article
Language:English
Published: KeAi Communications Co. Ltd. 2021-06-01
Series:Green Chemical Engineering
Subjects:
Online Access:http://www.sciencedirect.com/science/article/pii/S266695282030025X
_version_ 1797976389421367296
author Xian-Tai Zhou
Hong-Bing Ji
author_facet Xian-Tai Zhou
Hong-Bing Ji
author_sort Xian-Tai Zhou
collection DOAJ
description Substrate specificity is a hallmark of enzymatic catalysis. In this work, the biomimetic catalytic oxidation of styrene and cyclohexanone by iron (III) porphyrins and molecular oxygen was carried out, and remarkable differences in efficiency were observed. The specificity of the substrates for biomimetic catalytic oxidation was investigated by kinetics and mechanistic studies. Kinetics studies revealed that the oxidation of styrene followed Michaelis–Menten kinetics with KM ​= ​8.99 ​mol L-1, but the oxidation of cyclohexanone followed first-order kinetics with kobs ​= ​1.46 ​× ​10−4 ​s−1, indicating that the styrene epoxidation by metalloporphyrins exhibited characteristics of enzyme-like catalysis, while the oxidation of cyclohexanone was in agreement with the general rules of chemical catalysis. Different catalytic mechanisms for the two substrates were discussed by operando electron paramagnetic resonance spectroscopy, operando UV–vis spectroscopy, and KI/starch experiments. Substrate specificity was concluded to be attributed to the stability of high-valence species and oxygen transfer rate.
first_indexed 2024-04-11T04:50:10Z
format Article
id doaj.art-9ce914e2361b4d06b0eccaa288d79312
institution Directory Open Access Journal
issn 2666-9528
language English
last_indexed 2024-04-11T04:50:10Z
publishDate 2021-06-01
publisher KeAi Communications Co. Ltd.
record_format Article
series Green Chemical Engineering
spelling doaj.art-9ce914e2361b4d06b0eccaa288d793122022-12-27T04:39:37ZengKeAi Communications Co. Ltd.Green Chemical Engineering2666-95282021-06-0122217223Substrate specificity in the biomimetic catalytic aerobic oxidation of styrene and cyclohexanone by metalloporphyrins: kinetics and mechanistic studyXian-Tai Zhou0Hong-Bing Ji1Fine Chemical Industry Research Institute, Sun Yat-sen University, Guangzhou, 510275, ChinaFine Chemical Industry Research Institute, Sun Yat-sen University, Guangzhou, 510275, China; School of Chemical Engineering, Guangdong University of Petrochemical Technology, Maoming, 525000, China; Corresponding author.Substrate specificity is a hallmark of enzymatic catalysis. In this work, the biomimetic catalytic oxidation of styrene and cyclohexanone by iron (III) porphyrins and molecular oxygen was carried out, and remarkable differences in efficiency were observed. The specificity of the substrates for biomimetic catalytic oxidation was investigated by kinetics and mechanistic studies. Kinetics studies revealed that the oxidation of styrene followed Michaelis–Menten kinetics with KM ​= ​8.99 ​mol L-1, but the oxidation of cyclohexanone followed first-order kinetics with kobs ​= ​1.46 ​× ​10−4 ​s−1, indicating that the styrene epoxidation by metalloporphyrins exhibited characteristics of enzyme-like catalysis, while the oxidation of cyclohexanone was in agreement with the general rules of chemical catalysis. Different catalytic mechanisms for the two substrates were discussed by operando electron paramagnetic resonance spectroscopy, operando UV–vis spectroscopy, and KI/starch experiments. Substrate specificity was concluded to be attributed to the stability of high-valence species and oxygen transfer rate.http://www.sciencedirect.com/science/article/pii/S266695282030025XSubstrate specificityKineticsOxidationMetalloporphyrinsMechanism
spellingShingle Xian-Tai Zhou
Hong-Bing Ji
Substrate specificity in the biomimetic catalytic aerobic oxidation of styrene and cyclohexanone by metalloporphyrins: kinetics and mechanistic study
Green Chemical Engineering
Substrate specificity
Kinetics
Oxidation
Metalloporphyrins
Mechanism
title Substrate specificity in the biomimetic catalytic aerobic oxidation of styrene and cyclohexanone by metalloporphyrins: kinetics and mechanistic study
title_full Substrate specificity in the biomimetic catalytic aerobic oxidation of styrene and cyclohexanone by metalloporphyrins: kinetics and mechanistic study
title_fullStr Substrate specificity in the biomimetic catalytic aerobic oxidation of styrene and cyclohexanone by metalloporphyrins: kinetics and mechanistic study
title_full_unstemmed Substrate specificity in the biomimetic catalytic aerobic oxidation of styrene and cyclohexanone by metalloporphyrins: kinetics and mechanistic study
title_short Substrate specificity in the biomimetic catalytic aerobic oxidation of styrene and cyclohexanone by metalloporphyrins: kinetics and mechanistic study
title_sort substrate specificity in the biomimetic catalytic aerobic oxidation of styrene and cyclohexanone by metalloporphyrins kinetics and mechanistic study
topic Substrate specificity
Kinetics
Oxidation
Metalloporphyrins
Mechanism
url http://www.sciencedirect.com/science/article/pii/S266695282030025X
work_keys_str_mv AT xiantaizhou substratespecificityinthebiomimeticcatalyticaerobicoxidationofstyreneandcyclohexanonebymetalloporphyrinskineticsandmechanisticstudy
AT hongbingji substratespecificityinthebiomimeticcatalyticaerobicoxidationofstyreneandcyclohexanonebymetalloporphyrinskineticsandmechanisticstudy