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9 Other hierarchically assembled helicates: X. Sun, W. J. Darren, D.
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Fig. 1 Representation of the dimeric complex [Li3(1a)6Ti2]- in the solid
state (view down the Ti–Ti axis in ball-and-stick and side view in space
filling representation. In the space filling model the ligands of the two
monomeric units are shown in different colours (grey and ochre)) and
schematic representation of the “volume” of the monomeric versus the
dimeric compounds (bottom).
10 M. Albrecht, S. Mirtschin, M. de Groot, I. Janser, J. Runsink, G. Raabe,
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565.
In summary, we have presented a simple way to obtain highly
branched dendrimers with a bistitanium(IV)-trislithium core. The
compounds are derived by simple synthesis of dendritic cate-
cholate esters followed by complexation of three such derivatives
to titanium(IV). Lithium coordination leads to the formation of
dimeric, very dense, disc shaped dendrimers.
Acknowledgements
Financial support of this work by the DFG and the Fonds der
Chemischen Industrie is gratetfully acknowledged.
12 A. O. Obaseki, J. E. Steffen and W. R. Porter, J. Heterocycl. Chem.,
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13 M. Albrecht, M. Fiege, M. Baumert, M. de Groot, R. Fro¨hlich, L.
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Zauner, Eur. J. Org. Chem., 1999, 3165–3169.
15 M. Ballauff and C. N. Likos, Angew. Chem., 2004, 116, 3060;
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