Full Paper
the Ru=C bond, and in effect, the formation of a hexacoordinate struc-
ture seems to be inevitable for the mechanism.
Acknowledgments
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[15]
See the Supporting Information for details.
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W. D. Neudorff, D. Lentz, M. Anibarro, A. D. Schlüter, Chem. Eur. J. 2003,
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K. Skonieczny, D. T. Gryko, J. Org. Chem. 2015, 80, 5753–5763.
Indenylidene ruthenium complex 20 is commercially available from Umi-
core AG & Co. KG as catalyst “M2” (tradename). For its preparation, see:
S. Monsaert, R. Drozdzak, V. Dragutan, I. Dragutan, F. Verpoort, Eur. J.
Inorg. Chem. 2008, 432–440.
This work was financed by the Iuventus Plus Program of the
Polish Ministry of Science and Higher Education (grant number
IP2012001972, 2013–2015) and by the Polish Ministry of Sci-
ence and Higher Education (grant number N N204152436; syn-
thesis of complex 32). NMR spectroscopy studies presented in
this report were performed at the Biological and Chemical Re-
search Centre, University of Warsaw, established within the
project co-financed by the European Union from the European
Regional Development Fund under the Operational Programme
Innovative Economy, 2007–2013. The authors thank Umicore
AG & Co. KG for donation of the M2 complex.
[16]
[17]
[18]
Interestingly, we also synthesized 2-isopropoxy-6-methoxystyrene (66),
a ligand bearing two different coordinating alkoxy groups. The exchange
reaction with precursor 20 was performed in CH2Cl2 at 40 °C for 3 h and
led to the isolation of a green complex (83 %) as an inseparable mixture
of OMe- and OiPr-coordinated isomers.[13]
.
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We wish to acknowledge the use of a free version of ORTEP-3 for Win-
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Keywords: Homogeneous catalysis · Metathesis · Electronic
effects · Reaction mechanisms · Structure–activity relationships
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[12] In ref.[6b] Solans-Monfort also considered an associative mechanism for
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of the catalyst. Nevertheless, only the planar conformation of the 2,6-
disubstituted benzylidene ligand enables approach of the substrate to
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