ISMSC 2007 - Università degli Studi di Pavia

PSA 69
Assembly of Metallomacrocycles from Ditopic 2,2:6,2-Terpyridine Ligands
with Flexible Spacers.
Edwin C. Constable, Kate Harris, Catherine E. Housecroft, Markus Neuburger and Silvia
Schaffner
Department of Chemistry, University of Basel, Spitalstr. 51, 4056 Basel, Switzerland
The reaction of ditopic ligands containing two 2,2’:6’,2”-terpyridine metal-binding domains linked
by a variable spacer with transition metal ions can give metallopolymers [1] (copolymers with
alternating metal centres and ligands), discrete molecular macrocycles [2], or mixtures of the
two. The outcome of the coordination depends on the precise reaction conditions as well as the
nature of both the spacer and the transition metal ion.
Examples will be presented of metallomacrocycles of various sizes and nuclearities formed from
the reaction of such ditopic ligands containing a flexible oligo- or poly(ethylene glycol) spacer
with various cobalt salts.
N
N
N
O
O
0 n 65
n O N
Also presented will be a novel exchange reaction resulting from the reaction of these or 4’alkoxy-2,2’:6’2”-terpyridine
ligands with cobalt(II) ions in the presence of alcohols.
[1] S. Schmatloch, A. M. J. van den Berg, H. Hofmeier and U. S. Schubert, Designed
Monomers and Polymers, 2004, 7(1-2), 191-201.
[2] E. C. Constable, C. E. Housecroft, M. Neuburger, S. Schaffner and C. B. Smith, Dalton
Trans., 2005, 2259-2267.
N
N
PSA 70
Metal-Assembled Cages Observed by Sonic Spray Mass Spectrometry
Roger G. Harrison, Joseph S. Gardner, John D. Lamb, David V. Dearden
Department of Chemistry and Biochemistry, Brigham Young University, C100 BNSN, Provo,
Utah, 84602, USA
Supramolecular compounds are often difficult to characterize and metal-assembled
cages are no exception. We have found sonic spray ionization mass spectrometry (SSI MS) to
be effective in characterizing metal-assembled cages that are not easily observed using
conventional electrospray ionization mass spectrometry (ESI MS) techniques. 1 A palladiumassembled
resorcinarene-based cage first assembled by the Dalcanle group, 2 and a
palladium(II) triazine cage, first assembled by the Fujita group, 3 were characterized and their +1
molecular ion peaks observed using SSI MS. Along with these cages, new N,Nbis(pyridylmethyl)amine
resorcinarene cavitand-metal ion complexes were observed to have
peaks corresponding to tetranuclear complexes and cage complexes. 4 The molecular ion
peaks for these complexes were not detected with ESI MS. The soft ionization in SSI MS and its
relatively simple design provide another tool to characterize such supramolecular assemblies.
12 0
10 0
80
60
40
20
0
N
N
N
O O
O
O
1500 2000 2500 3000 3500 4000
m/v
O
OO O
O O O O
N
N
N
N N N
N N
N
Fe Fe N N N
Fe
Fe N
N N N N N
N
N
N
O O O
11 Cl- [1] Z. Takats, S. C. Nanita, R. G. Cooks, G. Schlosser, K. Vekey, Anal. Chem., 2003, 75, 1514-
1523.
[2] F. Fochi, P. Jacopozzi, E. Wegelius, K. Rissanen, P. Cozzini, E. Marastoni, E. Fisicaro, P.
Manini, R. Fokkens, E. Dalcanale, J. Am. Chem. Soc., 2001, 123, 7539-7552.
[3] S. Sakamoto, M. Yoshizawa, T. Kusukawa, M. Fujita, K. Yamaguchi, Org. Lett., 2001, 3,
1601-1604.
[4] J. S. Gardner, R. G. Harrison, J. D. Lamb, and D. V. Dearden, New J. Chem. 2006, 30,
1276-1282.