Book of Abstracts - Ruhr-Universität Bochum

P-49
ISBOMC `10 5.7 – 9.7. 2010 Ruhr-Universität Bochum
Bioinspired Catalysts With Bifunctional P,N - Ligands in Alkyne – Hydration
Anna Louisa Noffke a and Peter C. Kunz *a
a Department of Inorganic Chemistry I, Heinrich-Heine-University of Düsseldorf
Universitätsstr. 1, D-40225 Düsseldorf, Email: anna-louisa.noffke@uni-duesseldorf.de
Addition of water to terminal alkynes is a common path to carbonyl compounds. However, most
synthetic strategies suffer from rather intense conditions or low selectivity. In nature, the
tungstenoenzyme acetylene hydratase catalyzes the formation of ethanal from acetylene, for example
in pelobacter acetylenicus. 1 For higher alkynes, the hydration-reaction can be equally accelerated
using transition-metal catalysts with bifuntional ligands. 2 Systems similar to 1 (Fig. 1) perform with
high yields and splendit selectivity. 2
Fig. 1 Preparation of a Ru(II)-vinylidene complex and P,N-Ligands used.
With ruthenium(II)-complexes of the general formula [(Cp)Ru(L)2Cl] (Cp = cyclopentadienyl) bearing
our water-soluble, hemilabile P,N-ligands 3 (Fig. 1), catalytic activity in alkyne-hydration is observed
under certain conditions. The first mechanistic steps of this reaction involve formation of vinylidene
species which are subsequently aquated. In particular, the special role that is played by H-bonddonating
and/or accepting ligand-functionalities within this catalytic process is explored in further
detail.
References
1. S. Antony and C. A. Bayse, Organometallics 2009, 28, 4938–4944. (b) M. A. Vincent, I. H. Hillier,
G. Periyasamy and N. A. Burton, Dalton Trans. 2010, 39, 3816–3822.
3. (a) D. B. Grotjahn, D.A. Lev; J. Am. Chem. Soc. 2004, 126, 12232. (b) D.B. Grotjahn, Dalton
Trans. 2008, 6497.
2. (a) P. C. Kunz, M. U. Kassack, A. Hamacher, B. Spingler, Dalton Trans. 2009, 7741-7747. (b) P. C.
Kunz, G. J. Reiß, W. Frank, W. Kläui, Eur. J. Inorg. Chem. 2003, 3945-3951.
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