ISBN: 978-83-60043-10-3 - eurobic9

Eurobic9, 2-6 September, 2008, Wrocław, Poland
P11. New Model Complexes of Relevance to Artificial Photosynthesis
G. Berggren a , A. Thapper, P. Huang a , L. Eriksson b , M.F. Anderlund a , S. Styring a
a
Department of Photochemistry and Molecular Science, Uppsala University, Box 579, S-751 21 Uppsala,
Sweden
e-mail: Gustav.berggren@fotomol.uu.se.
b
Division of Structural Chemistry, Arrhenius Laboratory, Stockholm University, S-106 91, Stockholm, Sweden
Inspired by nature’s photosynthesis the Swedish Consortium for Artificial Photosynthesis works towards
molecular assemblies capable of producing H2 from H2O, using sunlight to drive the reaction [1]. A key part of
the natural system is a tetranuclear manganese-based catalyst, which provides the system with electrons via
stepwise oxidation of H2O [2, 3].
A model complex capable of fulfilling this role has been a long-standing goal of the scientific community.
Recently McKenzie and co-workers showed that a Mn-complex of a mononucleating, pentadentate, N4O ligand
(HL1) evolved oxygen when treated with Ce 4+ , a one electron oxidant [4]. To further investigate this system a
family of new ligands, mono- as well as dinucleating, based on this framework have been synthesized. The
corresponding Mn-complexes have been characterized by X-ray crystallography, MS, electrochemical methods,
magnetic susceptibility and EPR. Their capacity as catalysts for water oxidation using various chemical oxidants
has also been studied.
N
N
N
N
O
OH
HO
HL1 H 2L2
O
N
_____________________________________________________________________
130
N
N
N
N
N
N
N
O
OH
References:
[1] Sun, L.; Hammarström, L.; Åkermark, B.; Styring, S., Chem. Soc. Rev., 2001, 30, 36-49
[2] McEvoy, J. P.; Gascon, J. A.; Batista, V. S.; and Brudvig, G. W., Photochem. Photobiol. Sci., 2005, 4, 940-
949
[3] Ferreira, K. N.; Iverson, T. M.; Maghlaoui, K., Barber, J., Iwata, S., Science, 2004, 6, 1831-1838
[4] Poulsen, A. K.; Rompel, A.; McKenzie, C. J., Angew. Chem. Int. Ed., 2005, 44, 6916-6920
N
N
N
N
HL3
N
N
HL4
N
N
O
OH
O
OH
HO
N
O
N
N
N
H 2L5
N
N
N
O
OH
N