Chemistry and Catalytic Performance of Pyridyl-Benzimidazole Oxidomolybdenum(VI) Compounds in (Bio)Olefin Epoxidation

resumo

The chemistry and catalytic performance of the dichlorido complex [MoO2Cl2(pbim)] (1) [pbim = 2-(2-pyridyl)benzimidazole] in the epoxidation of olefins is reported. Complex 1 acts as a precatalyst and is more effective with tert-butyl-hydroperoxide (TBHP) as the oxidant than with aq. hydrogen peroxide: the cis-cyclooctene (Cy) reaction with TBHP gave 98 % epoxide yield at 70 degrees C/24 h. Catalyst characterization showed that 1 is transformed in situ to the oxidodiperoxido complex [MoO(O-2)(2)(pbim)] (2), with H2O2 and a hybrid molybdenum(VI) oxide solid formulated as [MoO3(pbim)] (3) with TBHP. The hybrid material 3 was prepared on a larger scale and explored for the epoxidation of the biorenewable olefins methyl oleate, methyl linoleate, and (R)-(+)-limonene. With TBHP as the oxidant, 3 acts as a source of soluble active species of the type 2. A practical method for recycling oxidodiperoxidomolybdenum(VI) catalysts for the Cy/TBHP reaction is demonstrated by using an ionic liquid as the solvent for the molecular catalyst 2.

palavras-chave

OXO-MOLYBDENUM COMPLEXES; METAL-ORGANIC FRAMEWORK; OLEFIN EPOXIDATION; STRUCTURAL ELUCIDATION; EFFICIENT CATALYSTS; DIOXOMOLYBDENUM(VI)-BIPYRIDINE COMPLEXES; HYDROTHERMAL SYNTHESIS; RHENIUM COMPLEXES; PEROXO COMPLEXES; DIOXO COMPLEXES

categoria

Chemistry

autores

Neves, P; Nogueira, LS; Gomes, AC; Oliveira, TSM; Lopes, AD; Valente, AA; Goncalves, IS; Pillinger, M

nossos autores

agradecimentos

This work was developed in the scope of the project CICECO - Aveiro Institute of Materials (POCI-01-0145-FEDER-007679) financed by national funds through the Fundacao para a Ciencia e a Tecnologia (FCT) (ref. UID/CTM/50011/2013) and Ministerio da Educacao e Ciencia (MEC) and when applicable, cofinanced by Fundo Europeu de Desenvolvimento Regional (FEDER) under the PT2020 Partnership Agreement. The FCT and the European Union are acknowledged for a Ph.D. grant to L. N. (PD/BD/109666/2015), and post-doctoral grants to P. N. (SFRH/BPD/110530/2015) and A. C. G. (SFRH/BPD/108541/2015), cofunded by Ministerio da Ciencia, Tecnologia e Ensino Superior (MCTES) and the European Social Fund through the program Programa Operacional Potencial Humano (POPH) of Quadro de Referencia Estrategica Nacional (QREN).

Partilhe este projeto

Publicações similares

Usamos cookies para atividades de marketing e para lhe oferecer uma melhor experiência de navegação. Ao clicar em “Aceitar Cookies” você concorda com nossa política de cookies. Leia sobre como usamos cookies clicando em "Política de Privacidade e Cookies".