ISMSC 2007 - Università degli Studi di Pavia

OP 3
Control of molecular architecture by steric and electronic factors: dinuclear
side-by-side vs tetranuclear [2x2] grid-type silver(I) complexes
Jason R. Price a , Yanhua Lan a , Geoffrey B. Jameson b , Alejandro Perez-Velasco c , Christopher A.
Hunter c and Sally Brooker a*
a
Department of Chemistry, University of Otago, PO Box 56, Dunedin, New Zealand
b
Institute of Fundamental Sciences, Chemistry, Massey University , PO Box 11222, Palmerston
North, New Zealand
c
Krebs Institute for Biomedical Science, Department of Chemistry, University of Sheffield,
Sheffield, United Kingdom
The well known plasticity of the coordination geometry of silver(I) offers the opportunity to
explore the effects that secondary bonding interactions have on supramolecular architectures.
While the co-ordination of relatively rigid poly-bidentate ligands to Ag(I) has been shown to form
[2x3], [3x3] and [4x5] grids with the Ag(I) ion adopting a distorted tetrahedral geometry,[1]
recent investigations by Constable et al [2-4] and Dunbar et al [5] with the bis-bidentate ligands
1 – 4 resulted in complexes where the Ag(I) did not form [2x2] grid complexes but instead
formed (a) a side-by-side arrangement of the ligands with Ag(I) ions in pseudo-square planar
geometries (dppz or 1, 2 & 4 with CF3SO3 - ),[2, 3] (b) a molecular propellor with Ag(I) ions in
trigonal prismatic geometries (4 with AsF6 - )[5] and (c) a more complex pentanuclear assembly in
which four silver(I) ions are three coordinated and one has a distorted tetrahedral geometry
(3).[4]
N
R
N N N
1 R = H (dppz)
2 R = Ph
3 R = SiMe 3
N
N
N
N N
4
N
R
N
N N N R
Recently, we reported some first row transition metal complexes with 5 (R=PhOMe) 6 where on
complexation with a metal ion which prefers a tetrahedral geometry [Cu(I)] resulted in a [2x2]
architecture, whereas with a metal ion that prefers an octahedral geometry generally a side-byside
arrangement resulted (ligand 5 placed equatorially and solvent molecules in axial sites).
The surprisingly diverse range of supramolecular architectures observed by Constable et al and
Dunbar et al inspired us to investigate the Ag(I) co-ordination chemistry of our existing bisbidentate
ligand. In addition, a family of ligands of general type 5, with varying phenyl ring
substituents, can be readily prepared and was expected to allow an examination of the effect of
weak, non-covalent interactions on the molecular architecture of the resulting complexes.[7] The
results of this study will be presented and discussed.
[1] M. Ruben, J. Rojo, F. J. Romero-Salguero, L. H. Uppadine, and J.-M. Lehn, Angew. Chem. Int.
Ed., 2004, 43, 3644.
[2] E. C. Constable, C. E. Housecroft, B. M. Kariuki, N. Kelly and C. B. Smith, C.R. Chimie, 2002, 5,
425.
[3] E. C. Constable, C. E. Housecroft, B. M. Kariuki, M. Neuburger and C. B. Smith, Aust. J. Chem.,
2003, 56, 653.
[4] E. C. Constable, C. E. Housecroft, M. Neuburger, S. Reymann and S. Schaffner, Chem.
Commun., 2004, 1056.
[5] B. L. Schottel, J. Bacsa and K. R. Dunbar, Chem. Commun., 2005, 46.
[6] Y. Lan, D. K. Kennepohl, B. Moubaraki, K. S. Murray, J. D. Cashion, G. B. Jameson, and S.
Brooker, Chem. Eur. J., 2003, 9, 3772.
[7] J. R. Price, Y. Lan, G. B. Jameson, and S. Brooker, Chem. Commun., 2006, 1491.
5
Supra-Biomolecular Tandem Assays
Andreas Hennig, Huseyin Bakirci, and Werner M. Nau
School of Engineering and Science, Jacobs University Bremen, Campus Ring 1, 28759
Bremen; e-mail: w.nau@iu-bremen.de
OP 4
Building on the work by others in the areas of supramolecular indicator displacement
assemblies [1-4] and enzyme assays [5-7], as well as our own recent contributions to these
research areas [8-14], we have devised a new approach to enzyme assays based on the simple
addition of water-soluble macrocycles and fluorescent dyes [15], which will be described for the
first time in a symposium.
[1] Ueno, A.; Kuwabara, T.; Nakamura, A.; Toda, F., Nature 1992, 356, 136-137.
[2] Koh, K. N.; Araki, K.; Ikeda, A.; Otsuka, H.; Shinkai, S., J. Am. Chem. Soc. 1996, 118, 755-
758.
[3] Sindelar, V.; Cejas, M. A.; Raymo, F. M.; Chen, W.; Parker, S. E.; Kaifer, A. E., Chem. Eur.
J. 2005, 11, 7054-7059.
[4] Nguyen, B. T.; Anslyn, E. V., Coord. Chem. Rev. 2006, 250, 3118-3127.
[5] Tawfik, D. S.; Green, B. S.; Chap, R.; Sela, M.; Eshhar, Z., Proc. Natl. Acad. Sci. USA 1993,
90, 373-377.
[6] Geymayer, P.; Bahr, N.; Reymond, J.-L., Chem. Eur. J. 1999, 5, 1006-1012.
[7] Das, G.; Talukdar, P.; Matile, S., Science 2002, 298, 1600-1602.
[8] Bakirci, H.; Koner, A. L.; Nau, W. M., Chem. Comm. 2005, 5411-5413.
[9] Bakirci, H.; Nau, W. M., Adv. Funct. Mat. 2006, 16, 237-242.
[10] Bakirci, H.; Koner, A. L.; Dickman, M. H.; Kortz, U.; Nau, W. M., Angew. Chem. Int. Ed.
2006, 45, 7400-7404.
[11] Koner, A. L.; Nau, W. M., Supramol. Chem. 2007, 19, 53-65.
[12] Hennig, A.; Roth, D.; Enderle, T.; Nau, W. M., ChemBioChem 2006, 7, 733-737.
[13] Hennig, A.; Florea, M.; Roth, D.; Enderle, T.; Nau, W. M., Anal. Biochem. 2007, 360, 255-
265.
[14] Hennig, A.; Ghale, G.; Nau, W. M., Chem. Comm. 2007, doi:10.1039/B618703J.
[15] Patent pending.