Substrate-Solvent Crosstalk-Effects on Reaction Kinetics and Product Selectivity in Olefin Oxidation Catalysis

resumo

In this work, we explored how solvents can affect olefin oxidation reactions catalyzed by MCM-bpy-Mo catalysts and whether their control can be made with those players. The results of this study demonstrated that polar and apolar aprotic solvents modulated the reactions in different ways. Experimental data showed that acetonitrile (aprotic polar) could largely hinder the reaction rate, whereas toluene (aprotic apolar) did not. In both cases, product selectivity at isoconversion was not affected. Further insights were obtained by means of neutron diffraction experiments, which confirmed the kinetic data and allowed for the proposal of a model based on substrate-solvent crosstalk by means of hydrogen bonding. In addition, the model was also validated in the ring-opening reaction (overoxidation) of styrene oxide to benzaldehyde, which progressed when toluene was the solvent (reaching 31% styrene oxide conversion) but was strongly hindered when acetonitrile was used instead (reaching only 7% conversion) due to the establishment of H-bonds in the latter. Although this model was confirmed and validated for olefin oxidation reactions, it can be envisaged that it may also be applied to other catalytic reaction systems where reaction control is critical, thereby widening its use.

palavras-chave

HYDROGEN-BONDING INTERACTIONS; STYRENE; EPOXIDATION; BENZALDEHYDE; COMPLEXES; PEROXIDE; FE

categoria

Chemistry, Multidisciplinary

autores

Sales, RN; Callear, SK; Vaz, PD; Nunes, CD

nossos autores

agradecimentos

Fundacao para a Ciencia e Tecnologia (FCT), Portugal funded this research and is acknowledged for financial support through grants UIDB/00100/2020 and UIDP/00100/2020.

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".