DUGi

Observation of Fe(V)=O using variable-temperature mass spectrometry and its enzyme-like C–H and C=C oxidation reactions

http://dugi.udg.edu/item/http:@@@@hdl.handle.net@@2072@@300386

Oxo-transfer chemistry mediated by iron underpins many biological processes and today is emerging as synthetically very important for the catalytic oxidation of C–H and C=C moieties that are hard to activate conventionally. Despite the vast amount of research in this area, experimental characterization of the reactive species under catalytic conditions is very limited, although a Fe(V)=O moiety was postulated. Here we show, using variable-temperature mass spectrometry, the generation of a Fe(V)=O species within a synthetic non-haem complex at −40 °C and its reaction with an olefin. Also, with isotopic labelling we were able both to follow oxygen-atom transfer from H2O2/H2O through Fe(V)=O to the products and to probe the reactivity as a function of temperature. This study pioneers the implementation of variable-temperature mass spectrometry to investigate reactive intermediates

We thank the Engineering and Physical Sciences Research Council and WestCHEM for funding, and Bruker Daltonics for collaboration. L. C. thanks the Royal Society and Wolfson Research for a merit award. M. C. and X. R. thank the Ministerio de Ciencia e Innovacion (MICINN) for Project CTQ2009-08464, and Generalitat de Catalunya for Institucio Catalana de Recerca i Estudis Avancats Academia Awards. M. C. thanks the European Research Foundation for Project ERC-2009-StG-239910. I. P. thanks MICINN for a PhD grant. L. C. and M. C. thank COST Action D40