الفهرس 
EXPERMENT ALOnly 14 pages are availabe for public view
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Abstract
This thesis includes three chapters; the introduction, experimental and results and discussions.
-CHAPTER (1)
In this chapter. a literature survey of the pervious studies carried out on macrocyclic compounds
and their complexes with transition metal ions is given. This survey includes electronic absorption
spectra in the UV and visible regions, studies on the metal chelates formed with uirrerent
transition metal ions, the uirrerent techniyu<.:s or structure elucidation of metal macrocyclic
complexes.
- CHAPTER (2)
This chapter describes the experimental part where it includes the preparation of the Fe(IJJ),
Co(Il), Ni(II) and Cu(JJ) macrocyclic complexes by template reaction. It comprises also a
description of the instruments used for spectrophotometric, conductometric, IR, thermal analysis,
electron spin resonance spectroscopy of Cu(Il) complexes, x-ray
diffraction, scanning electron microscope, measurements, catalytic studies and
meas:Jrements.
magnetic electrical
susceptibility conductivity
- CHAPTER (3)
This chapter includes the results and discussions and it comprises to three main parts:
A- Structure elucidation of the prepared macrocyclic complexes:
The structures of the solid complexes were firstly confirmed by elemental analysis of the isolated
chelates. Data of elemental analysis show satisfactory agreement with the proposed formula. All
the solid
complexes are soluble in DMF but insoluble in common organic solvents and do not posses sharp
melting points but decompose on heating above 530 °C. The molar conductivities of the complexes in
DMF indicate that all o:the complexes arc of ionic nature.
The results of thermal analysis of some selected solid macrocyclic complexes show that they degrade
in three stages. The first step in the decomposition sequence corresponds to the loss of physically
combined water molecules from the outer surface or interstice of the crystal lattice. The second
step within the temperature range 140- 530 °C represent the thermal decomposition of the CH3 and
CH2 groups support the proposed structure. The CH 3 groups start to decompose at 140”C followed by
CH2
groups and the compensation of nitrogen atoms to give N 2 gas. The latter
decomposed in the final step forming CoO, NiO or CuO as a final product. The number of coordinated
water molecules and the percent of mctnl ions were ..:ulculutcu lh>lll the weight loss 011 til..:
TU curves whose values are in good agreement with those obtained from elemental analysis.
Magnetic susceptibility mensurements were carried out at room temperature using Gouy’s balance
method. The efT. values of the selected complexes show normal values for distorted octahedral
complexes.
Further support of the mode of bonding taking place in the solid complexes was obtained by IR
spectroscopy. The IR absorption spectra of the solid macrocyclic complexes with ligand molecules
based on diphenylamine and diketones. !R spectra of macrocyclic complexes Jormed between
a-phenylene-diamine and p-phenylene-diamine with acetylacetone, benzoylacetone and
dibenzoylmethane.
The.: I R spectrum ur u-phc.:nylc.:nc.:diamim: and p-phenylenediamine show broad bands at 3362-3373
cm·1 which are due to the stretching vibrational mode of the NH 2 groups and the strong band
at 1596-1655 cm·1 due to the stretching vibration of the C=O expected to present in the
diketone molecule. The IR spectra of Fe3·, Co2 +, Ni 2+ and Cu 2+
complexes show the absence of the first two bands with the appearance of new sets of bands at
1602-1657 cm. 1 due to the stretching vibration of the C=N group (usy•n e-N) resulting from
the condensation of C=O and Nl-12
groups of the acetylacetone and a-phenylenediamine respectively in the
template reaction. These bands are found at so lower frequencies due to the participation of the
nitrogen atom of the azomethine group in the coordination bonds. The stretching vibration bands of
the active methylene group (uCJd of the diketone moiety suffer a shift toward lower frequency side
as a result of electron delocalization due to complex fomJarion. The metal to nitrogen bonds
(u’vf.N) give rise to a medium strong bands at 370-461 cm·1 according to formation of macrocyclic
complexes.
Th e eIectrom.c absorpti.on spectra of Fel+, Co>·+ , N.1>-+ and Cu 2+ macro complexes were scanned
in the UV-visible range in solution using DMF
as solvent and in solid state using Nujol mull technique. The spectra show bands due to n-n’
transitions within the ligand (UV region), M L or L M transitions nnd d-el
trnnsitions in fnr visible region.
The electronic spectra of the majority of Fe3+ macro complexes show two broad bands and a shoulder
within the ranges 13552-19205 cm·1 , 17637-19841 cm·1 and 22026-2666() cm·1 corresponding
to
1g---> T 1 g, A
1g---> T2g and A
1g-> A
1 g transitions in octahedral field.
On the other hand, spectra of Co2+ macro complexes are characterized
by two broad bands within the ranges I 5026-5 I 097 :m· 1 and
transitions, respectively. This indicates an octahedral environment around the Co2+ ions. All the
investigated Ni 2+ complexes show diamagnetic behavior except those of a-phenylenediamine with
acetylactone and
dibenzoylmethane which showed paramagnetic character. The electronic spectra of the other two
Ni!· macro complexes show two broad bands within the ranges 15198-22963 cm- 1 and
21032-24752 cm- 1 assignable to the 3A 2g --> 3T 1 g (F) and 3 A 2g --> 3T 1 g (P)
transitions, respectively in
octahedral field. The electronic srectra of Cu(ll) comrlexes show two
broad band within 13774-20284 cm- 1 and 16103-21459 em·’ which can be assigned, respectively to
2E2g ----> 2B 1 g and 2A 1 g ....... 2B 1 g transition in a tetragonally distorted octahedral
configuration.
z-r
1- R 1 R 2 R 3 R, CHJ
2- R 1 R 3 CH 3 , R 2 R, Ph
3- R 1 R 2 R 3 R, Ph
l’ , • ,’ ... ’
M h: , Co’ . Ni’ ami l’u’
The room temperature of ESR spectra of macrocyclic Cu (II) complexes with
o-phynelenediamine-acetylacetone, p-phynelenediamine acetylacetone and p-phynelenediamine -
dibenzoylmethane showed
anisotropic spectra with g
> g.t characteristic for distorted elongated
Summary
v
tetragonal copper (II) complexes with d/ _, 2 ground state. The shifting of a g-value from 2.0023
in transition metal complexes is due to the mixing via spin-orbit coupling of the metal orbitals
involved in molecular orbitals containing the unpaired electron(s), with the empty or
filled ligand
orbitals. For Cu (II) complexes, the g
value is a sensitive parameter to
indicate degree of covalem:y. For a covalent complex, g:r = 2.3 or more. The polycrystalline x-band
ESR spectra of Cu(ll) macrocyclic complex with o-phynelendiamine and dibenzoylmethane show
anisotropic nature
characteristic of tetragonal compressed with d} ground state and
g.L value > g • The value of transition energy (Ed} - Edxy.dxz) corresponding to B lg_, 2Eg
was calculated. Deviation in the g value of this complex from 2.0023 of free electron
is due to the covalence property
as gathered from the G value which indicated to the interaction in the solid complexes. ESR spectra
of Cu(II) complexes with benzoyiacetone, o-phynelenediamine and p-phynlenediamine are show splited
giving rise to three g value. The weak and broad signals are due to the polymeric nature of these
complexes. The broad signal is conlllHlll in nwny copper complexes and is attributed to the dipolar
broadening enhanced spin lattice relaxation property.
The X-Ray diffraction has been made for the C’o2 \o-phenylene diamine-acetyl acetone), Co2
•(o-pheny lenediamine-benzoyiacetone ), Cu2+(o-phenylenediamine-acetylacetone) and Ni2+(
o-phenylenediamine
acetyl--acetone) macrocomplexes. All the prepared complexes show a peaks at 28 about 5.5-15.7 A
that indicate the presence of layer structure and show the absence of a single phase structure.
Scanning electron microscope for Cu2+ (o-phenylenediamine-acetyl acetone) macrocyclic complex. The
micrograph shows n species of different size ranging from 50 j.un up to 150 jlm. the perfect shape
of the
Summary
vi
particles give an indication that the prepared materials are composed of multiphase as represented
from the XRD. It is also seemed to have layer structure.