IJUP08 - Universidade do Porto

Anchoring of macrocycle compounds onto nanostructured
carbon materials for catalytic applications
Dalila Teixeira, 1 Delfina Barros, 1 Susana L. H. Rebelo, 1
M. F. R. Pereira, 2 J. J. M. Órfão, 2 Cristina Freire 1
REQUIMTE, Departamento de Química, Faculdade de Ciências, Universidade do Porto, 4169-007
Porto.
The immobilisation of transition metal complexes with catalytic properties onto supports is
a theme of intense research, due to its importance towards the goals of Green Chemistry.
Porphyrins and salen-type metal complexes have been succeeded on homogeneous
catalytic oxidations. However, their catalytic properties (catalyst stability and recycling)
can be further improved by immobilisation onto solid supports. Carbon materials are
unique supports as they can provide a variety of oxygen surface groups at the edges/defects
of graphene sheets that can be tailored by adequate thermal/chemical treatments, besides
the inherent chemical/physical reactivity associated with the graphene sheets which are
hydrophobic and present low polarity and a rich -electron density. In this project we
endeavour to synthesise and immobilise porphyrins and salen-type metal complexes,
Figure 1, that exhibit catalytic properties in the oxidation of organic pollutants, onto
nanostructured carbon materials: multi-walled carbon nanotubes (MWCNTs), carbon
xerogels (CX) and templated carbons (CMK).
Ar
a) Cl
b)
N
Ar M Ar
N L N
Ar
N
M = 2H, Zn(II), Ni(II), Cu(II)
Au(III), Fe(III), Mn(III)
Ar =
Ar =
Figure 1: Molecular structures of a) porphyrins and b) salen-type metal complexes.
Cl
F
F
In this work we report the preparation and the characterisation of several porphyrins and
salen-type ligands and the corresponding metal complexes, M=Fe(III), Mn(III), Au(III),
Ni(II), Cu(II) and Zn(II). These compounds will be grafted to the untreated carbon
materials (MWCNT, CX and CMKs) and fullerenes (reference material) by covalent
bonding. The covalent anchored procedure will be achieved by utilizing 1,3-dipolar
addition of azomethine ylides and cyclopropanation under Bingel reaction conditions.
Acknowledgments: This work is funded by Proj. IPG58 de Investigação Científica na Pré-
Graduação 2007 (Universidade do Porto e Caixa Geral de Depósitos).
F
F
F
HO
N N
Mn
O O
Cl
OH
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