Introduction
Tetraaza macrocyclic complexes have been synthesized as models for metalloporphyrins, chlorophyll,
metallocprrins, hemoglobin and vitamin B
12
due to their intrinsic structure properties. There have beeen various
applications of tetraaza macrocyclic complexes, such as antimicrobial, luminescent sensor, artificial restriction
enzymes for cleaving DNA and RNA, magnetic and catalytic properties
(Ahmad Husain et al., 2011). Metal template
syntheses of macrocyclic ligands have been useful and effective method to obtain new macrocyclic ligands during the
last three decades. The metal ions as templates and many macrocyclic ligands have been prepared by the condensation
of formaldehyde with amide. Template synthesis of macrocyclic complexes is simple reaction as formaldehyde links
between two amine moieties to form methylenediamine linkages (-N-CH
2
-N-). The methylenediamine linkage is
unstable when it contains primary amines, R-NH
2
in which R is either aromatic or aliphatic group, such as
methylamine, propylamine and phenylethylamine, which can condense with formaldehyde to from a new N-C bond
(Yi He et al., 2003).
In this work, the Ni(II) complex containing the 14-membered tetraaza macrocyclic ligands has been
synthesized in a one-pot reaction involving nikel(II) chloride, ethylenediamine, formaldehyde and butylamine in
95% absolute ethanol.
Experimental
Materials and Method
NiCl
2
·6H
2
O, ethylenediamine, formaldehyde, butylamine and perchloric acid were all purchased from
commercial source and used as received.
Caution!
Perchlorate salts of metal complexes are potentially explosive.
Only a small amount material should be prepared, and it should be handled with care. IR spectra (4000 - 400 cm
-1
)
were recorded with FT - IR spectrometer as a KBr disk. The visible spectra were recorded with a Shimadzu Lambda-
1600 UV - Vis spectrophotometer in DMSO. Single crystal suitable for x-ray crystallographic analyses were obtained
by the slow evaporation of solvent from the acetonitrile : ethanol solution of complex at room temperature. X-ray data
for complex were collected at 293 K on a Bruker SMART APEX CCD area-detector diffractometer with graphite
monochromated Mo K
D
- radiation (K = 0.71073 Å). The data integration and reduction were processed with SAINT
(Bruker, 2003) software. An empirical absorption correction was applied to the collected reflections with SADABS
program (Bruker, 2003). The linear absorption coefficients, scattering factors for the atoms and the anomalous
dispersion corrections were taken from the International Tables for x-ray crystallography. All the structure was solved
by the direct method using SHELXS-97 program (Sheldrick, 2008) and was refined on
F
2
by the full-matrix least-
squares technique using the SHELXL-97 program. Figures were drawn using Mercury - 3.0 (Macrea et al., 2008) and
Diamond - 3.0 (Brandenburg, K. et al., 2005).
Synthesis of [NiL](ClO
4
)
2
To a 95% absolute ethanol (10 mL) of NiCl
2
·6H
2
O (2.3058 g, 10 mmol) were added 99% ethylenediamine
(1.3 mL, 20 mmol) in 95% absolute ethanol (10). After the mixture was completely clear blue solution then, added
218
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