| Přispěvatelé: |
IRCELYON, ProductionsScientifiques, BIOVERT (BIOVERT), Institut de recherches sur la catalyse et l'environnement de Lyon (IRCELYON), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC) |
| Popis: |
International @ BIOVERT+ASO:PAF:CCO:EKU; International audience; We have recently introduced ľ-nitrido diiron macrocyclic complexes as bio-inspired catalysts combining structural features of soluble methane monooxygenase (diiron site) and cytochrome P-450 (porphyrinoid supporting ligands) [1-6]. Such a binuclear construction was shown to be particularly efficient in the oxidation reactions using H2O2 under mild and clean conditions. These diiron porphyrin and phthalocyanine complexes are much more active in the oxidation of alkanes than their mononuclear counterparts [1]. ľ-Nitrido diiron phthalocyanines with FeIIIN=FeIV structural unit catalyze the oxidation of methane [2], alkylaromatic compounds [3] and benzene [4]. Available reactivity and spectroscopic data indicate an involvement of high-valent diiron oxo species in these demanding reactions [1,5]. Herein we show that ľ-nitrido diiron phthalocyanines are also capable of performing an efficient C-C bond formation exemplified by hydroacylation of olefins [6]: This simple and practical method for the synthesis of methylketones from olefins and acetaldehyde in the presence of readily available and non-toxic iron catalyst (typically 0.01 mol % to olefin) presents a clean alternative to traditional methods based on the use of large amounts of expensive Rh and Ru complexes. This protocol showing 100 % atom efficiency can be applied for the hydroacylation of linear and cyclic aliphatic olefins, alkenyl substituted aromatic compounds and olefins containing readily oxidizable functions without the need of protecting/deprotecting procedures. The reaction is particularly suitable for the gram-scale syntheses. To rationalize the remarkable reactivity of the ľ-nitrido diiron species a tentative mechanism has been proposed. We will also present our recent findings on the dehalogenation of heavily halogenated compounds mediated by diiron complexes. We have isolated and fully characterized intermediates involved in the catalytic cycle. High turnover numbers and high dehalogenation degrees can be achieved under very mild conditions (water, 20-60°C). Mechanistic aspects of this unusual reactivity will be discussed. References [1] E.V. Kudrik, P. Afanasiev, L.X. Alvarez, P. Dubourdeaux, M. Clémancey, J.-M. Latour, G. Blondin, D. Bouchu, F. Albrieux, S.E. Nefedov and A.B. Sorokin, Nature Chemistry 4 (2012) 1024. [2] a) A.B. Sorokin, E.V. Kudrik and D. Bouchu, Chem. Commun. (2008) 2562; b) A.B. Sorokin, E.V. Kudrik, L.X. Alvarez, P. Afanasiev, J.M.M. Millet and D. Bouchu, Catal Today 157 (2010)149. [3] Ü. Isci, P. Afanasiev, J.M.M. Millet, E.V. Kudrik, V. Ahsen and A.B. Sorokin, Dalton Trans. (2009) 7410. [4] E.V. Kudrik and A.B. Sorokin, Chem. Eur. J. 14 (2008) 7123. [5] P. Afanasiev, E.V. Kudrik, J.M.M. Millet, D. Bouchu and A.B. Sorokin, Dalton Trans. 40 (2011) 701. [6] L.X. Alvarez, E.V. Kudrik and A.B. Sorokin, Chem. Eur. J. 17 (2011) 9298. |
