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Introduction

 

Quantum-chemistry based research in my group aims at understanding of mechanistic fundamentals of main-group and transition-metal based modification of chemical bonds in relation to general catalysis and solar energy conversion/storage technologies. At present, we are active within the following areas:

(A) Activation/transfer of H2 with Lewis donor-acceptor complexes including the so-called frustrated Lewis pairs;

(B) Key components/processes of artificial photochemical systems, i.e. catalysis of water oxidation and dye-regeneration chemistry in Grńtzel solar cells;

(C) Transition metal-catalyzed selective hydrogen transfer and bond-activation.

 

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Focus Areas:

A. I have recently started up new a research direction which involves computational studies of interactions between H2 and the so-called frustrated Lewis pairs (FLPs).[1] This is a new area of independent research which I plan to strengthen and expand. In a very short time-period I have published six papers,[2],[3],[4],[5],[6],[7] which already have attracted attention on the international level.

 

B. I have been involved in investigation of fundamental processes that are highly relevant for solar energy conversion. In-detail computational study, of which I am the corresponding author, provided a rationale for experimentally observed reactivity and structural properties of novel highly efficient Ru-based water oxidation catalysts, as well as proposed novel binuclear reaction pathway. These results were recently published in Angewandte Chemie.[8] Very recently, we have discovered involvement of the ligand-reorganization energy and the intramolecular Lewis acid-base interactions in the key step of water oxidation. Early study, of which I am the corresponding co-author, was recently accepted for publication in Angewandte Chemie.[9]

 

Additionally, we[10]a were the first to address the interaction of the components of the iodide/triiodide redox couple with the oxidized Ru-based and recently10b metal-free photo-sensitizers, proposing a complete mechanism of the process which is central for the dye sensitized solar cells (DSSC). Our results,10a later confirmed by independent theoretical and experimental studiews,[11] also allowed rationalization of other effects.[12]

 

C. Since a few years back, I have been involved in investigation of metal-catalyzed hydrogen transfer reactions and very recently we[13] computationally identified a novel acyl intermediate that plays a central role in the racemization of sec-alcohols using the (η5-pentaphenyl(cyclopentadienyl)Ru(CO)2Cl catalyst. The computationally proposed acyl intermediate was later detected by in situ FT-IR and NMR spectroscopy.[14] We have also in independent work predicted a novel reaction pathway for the dehydrogenation via C-H activation catalyzed by the methylrhenium trioxide (CH3ReO3, MTO).[15]

 

 

Perspectives:

  1. Building upon our ideas and results, will advance further the knowledge about FLP-based hydrogen transfer/activation processes including those relevant for development of hydrogen storage methodologies. Based on promising preliminary results and our expertise, we also aim to address capture and chemically relevant activation of greenhouse gases, N2O and CO2, with FLP-like donor-acceptor complexes in homogeneous and in the long term heterogeneous conditions. We also aim to explore more general Lewis donor-acceptor complexes.
  2. Our results generated new mechanistic lines of thought regarding fundamental intra- and inter-molecular donor-acceptor interactions in artificial photochemical systems, which we will thoroughly explore in order to advance understanding of dye regeneration chemistry in Grńtzel solar cells and the transition-metal catalyzed water oxidation.
  3. Based on our earlier results, we will study mechanistic aspects of (i) metal-cyclopentadienyl and metal-hydroxycyclopentadienyl catalysts with the ruthenium, iron and iridium metal centers;[16] (ii) oxygen-transfer and C-H bond activation catalyzed by the methylrhenium trioxide (CH3ReO3).

 

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Selected references



[[1]] Stephan, D.; Erker, G.; Angew. Chem. Int. Ed. 2010, 49, 46.

[[2]] NyhlÚn, J.; Privalov, T. J. Mol. Catal. A: Chem. 2010, 324, 97-103.

[[3]] NyhlÚn, J; Privalov, T. Eur. J. Inorg. Chem. 2009, 2759.

[[4]] Privalov, T. Eur. J. Inorg. Chem, 2009, 2229.

[[5]] Privalov, T. Chem. Eur. J., 2009, 15, 1825.

[[6]] Privalov, T. Dalton Transactions, 2009, 1321.

[[7]] NyhlÚn, J; Privalov, T. Dalton Transactions, 2009, 5780.

[[8]] NyhlÚn, J.; Duan, L.; ┼kermark, B.; Sun, L.; Privalov, T. Angew. Chem., Int. Ed. Engl., 2010, 49, 1773.

[[9]] Tong, L; Duan, L; Xu, Y.; Privalov, T.; Sun, L. Angew. Chem. Int. Ed. 2010, in press.

[[10]] a) Boschloo, G.; Hagfeldt, A.; Svensson, P. H.; Kloo L., Privalov, T. J. Phys. Chem. C, 2009, 113, 783; b) NyhlÚn, J.; Boschloo, G.; Hagfeldt, A.; Svensson, P. H.; Kloo L., Privalov, T. ChemPhysChem, 2010, 11, 1858-1862.

[[11]] Schiffmann, F.; VandeVondele, J., Hutter, H.; Urakawa, A.; Wirz, R.; Baiker, A. Proc. Natl. Acad. Sci. USA, 2010, 4830 ľ 4833.

[[12]] Kusama, H.; Suigihara, H.; Sayama, K. J. Phys. Chem. C 2009, 113, 20764 ľ 20771.

[[13]] NyhlÚn, J; Privalov, T.; Bńckvall, J. - E., Chem Eur. J, 2009, 15, 5220 ľ 5229; T.P. is corresponding co-author of this article.

[[14]] Jenny B. ┼berg, Jonas NyhlÚn, BelÚn Martin-Matute, Timofei Privalov and Jan-E. Bńckvall J. Am. Chem. Soc., 2009, 131 (27), pp 9500ľ9501.

[[15]] Karlsson, E. A.; Privalov, T. I., Chem. Eur. J., 2009, 15, 1862-1869.

[[16]] a) Casey, C.; Guan, H. J. Am. Chem. Soc. 2009, 131, 2499; b) Haak, R.; Berthiol, F.; Jerphagnon, T.; Gayet, A.; Tarabiono, C.; Postema, C.; Ritleng, V.; Pfeffer, M.; Janssen, D.; Minnaard, A.; Feringa, B.; de Vries, J. J. Am. Chem. Soc. 2008, 130, 13508.