Page 53 - Book of Abstracts

th
8 Biannual Conference on Chemistry - CHEM 08

Synthesis, Solvatochromism, Potentiometric, Catalytic,

Thermal and Biological Activity of Copper Mixed-Ligand
Complexes Derived from Trifluoroacetylacetone and

Dinitrogen Ligands
Wolfgang Linert , Nelly H. Mahmoud , Azza. A. Abou-Hussein
1
2
2
1 Institute of Applied Synthetic Chemistry, Vienna University of
Technology, Getreidemarkt, 9/163 - AC, 1060 Vienna, Austria;
wolfgang.linert@tuwien.ac.at; 2 Department of Chemistry, Girl’s College
for Arts, Science and Education, Ain Shams University, Cairo, Egypt .
Email: nelly.mahmoud@women.asu.edu.eg

ABSTRACT
Mixed ligand Cu(II) complexes of the empirical formula;
[Cu(L)(TFAA)]X, where L represents 2,2´-bipyridine (Bipy), 1,10´-
phenanthroline (Phen) or 4,7-diphenyl-1,10´- phenanthroline (Dphen), 1,1,1-
Trifluoro-2,4-pentanedione (HTFAA) and X is the counter ion (BF4 or ClO4 )
-
-
were synthesized and characterized by spectroscopic, magnetic, molar
conductance, elemental and thermal analysis. Solvatochromic studies reveal
that all the complexes show bathochromic shifts. A square planar geometric
structure is proposed for perchlorate and tetrafluoroborate complexes.
Spectral properties support square planar structure provided by the
N2O2 chromophores. The copper mixed ligand complexes exhibit promising
catalytic activity towards the decomposition of hydrogen peroxide via a first
order reaction, the behaviour in catalytic efficiency is in the order perchlorate
complexes ˃ tetrafluoroborate ones. Potentiometric studies of the aqueous
mixed ligand copper complexes were carried out. The protonation constants
of the free ligands and the stability constants of the complexes were
determined using pH titration. The sequence of stability of ternary complexes
with respect to their ligands decreases in the order: Bipy˃ o-Phen˃ Dphen.
The kinetic and thermodynamic parameters were calculated using Coat-
Redfern equation, the stability of the complexes were determined and it was
in accordance with the results obtained from potentiometric studies. The
synthesized complexes have been examined for their antimicrobial activity.
The obtained results indicate that the complexes exhibit higher antimicrobial
activity than the ligands, also show that perchlorate complexes have higher
activity than tetrafluoroborate and the growth of inhibitory activity of the
complexes follows the order Bipy˃Phen˃Dphen.

BOOK OF ABSTRACTS CHEM 08 (2020) Page 52