Characterization and catalytic activity of 2,6-dichlorophenyl substituted iron(III) porphyrin supported on silica gel and imidazole propyl gel

Página do item simplificado
dc.contributor.authorIamamoto, Y.
dc.contributor.authorCiuffi, K. J.
dc.contributor.authorSacco, H. C.
dc.contributor.authorIwamoto, L. S.
dc.contributor.authorNascimento, O. R.
dc.contributor.authorPrado, CMC
dc.contributor.institutionUniversidade de São Paulo (USP)
dc.contributor.institutionUniversidade Estadual Paulista (Unesp)
dc.date.accessioned2014-05-20T15:27:03Z
dc.date.available2014-05-20T15:27:03Z
dc.date.issued1997-03-07
dc.description.abstractIn this work we have made use of the study of the interaction between Fe(TDCPP)(+) and the axial ligands OH- and imidazole in order to help characterize the heterogenized catalysts Fe(TDCPP)SG and Fe(TDCPP)IPG through UV-VIS and EPR spectroscopies and thus, better understand their different catalytic activity in the oxidation of cyclohexane by PhIO. We have found out that in Fe(TDCPP)SG (containing 1.2 X 10(-6) mol Fe(TDCPP)(+)/g of support), the FeP bis-coordinates to silica gel through Fe-O coordination and it is high-spin (FeP)-P-III species. In Fe(TDCPP)IPG 1 (containing 1.1 X 10(-6) mol Fe(TDCPP)(+) and 2.2 X 10(-4) mol imidazole/g of support), the FeP is bis-ligated to imidazole propyl gel through Fe-imidazole coordination and using NO as a paramagnetic probe, we present evidence that Fe(TDCPP)(+) is present as a mixture of low-spin (FeP)-P-III and (FeP)-P-II species. This catalyst led to a relative low yield of cyclohexanol (25%) because the bis-coordination of the (FeP)-P-III to the support partially blocks the reaction between Fe(TDCPP)(+) and PhIO, thus leading to the formation of only a small amount of the active species Fe-IV(OP+, while the (FeP)-P-II species do not react with the oxygen donor. Increasing the amount of Fe(TDCPP)(+) and decreasing the amount of imidazole in the support led to the obtention of high-spin (FeP)-P-III EPR signals in the spectra of Fe(TDCPP)IPG 5 (containing 4.4 X 10(-6) mol Fe(TDCPP)(+) and 2.2 X 10(-5) mol imidazole/g of IPG), together with low-spin (FeP)-P-III species. This latter catalyst led to better cyclohexanol yields (67%) than Fe(TDCPP)IPG 1. Fe(TDCPP)IPG 5 was further used in a study of the optimization of its catalytic activity and in recycling experiments in the optimized conditions. Recycling oxidation reactions of Fe(TDCPP)IPG 5 led to a total turnover number of 201 and total cyclohexanol yield of 201%, which could not be attained with Fe(TDCPP)Cl in homogeneous solution (turnover = 96) due to the difficulty in recovering and reusing it.en
dc.description.affiliationUNIV SAO PAULO,INST FIS SAO CARLOS,SAO CARLOS,SP,BRAZIL
dc.description.affiliationUNESP,INST QUIM,ARARAQUARA,SP,BRAZIL
dc.description.affiliationUnespUNESP,INST QUIM,ARARAQUARA,SP,BRAZIL
dc.format.extent405-420
dc.identifierhttp://dx.doi.org/10.1016/S1381-1169(96)00342-1
dc.identifier.citationJournal of Molecular Catalysis A-chemical. Amsterdam: Elsevier B.V., v. 116, n. 3, p. 405-420, 1997.
dc.identifier.doi10.1016/S1381-1169(96)00342-1
dc.identifier.issn1381-1169
dc.identifier.urihttp://hdl.handle.net/11449/37099
dc.identifier.wosWOS:A1997WL78200012
dc.language.isoeng
dc.publisherElsevier B.V.
dc.relation.ispartofJournal of Molecular Catalysis A: Chemical
dc.relation.ispartofjcr4.397
dc.rights.accessRightsAcesso restrito
dc.sourceWeb of Science
dc.subjectcyclohexanept
dc.subjectimidazole propyl gelpt
dc.subjectiron(III)porphyrinpt
dc.subject2,6-dichlorophenyl porphyrinpt
dc.subjectoxidationpt
dc.subjectporphyrinpt
dc.subjectsupported catalystspt
dc.titleCharacterization and catalytic activity of 2,6-dichlorophenyl substituted iron(III) porphyrin supported on silica gel and imidazole propyl gelen
dc.typeArtigo
dcterms.licensehttp://www.elsevier.com/about/open-access/open-access-policies/article-posting-policy
dcterms.rightsHolderElsevier B.V.
unesp.author.orcid0000-0001-8270-0286[2]
unesp.author.orcid0000-0003-0761-5086[1]

Arquivos

Licença do Pacote
Agora exibindo 1 - 1 de 1
Nenhuma Miniatura disponível
Nome:
license.txt
Tamanho:
1.71 KB
Formato:
Item-specific license agreed upon to submission
Descrição:

Coleções

Artigos