Complexes of CdX
2 (X
=
Cl, Br, I) and ZnCl
2 with the bidentate 3
,5-dimethylpyrazole-1-carboxamidine (HL) ligand were synthesized and characterized. Single crystals were prepared from the ...corresponding metal ammine complexes and
HL·HNO
3
at a self-controlled rate. The complex formation and the thermal decomposition are explained using the HSAB principle. DFT calculations have been performed.
The complex formation of 3
,5-dimethylpyrazole-1-carboxamidinium nitrate,
HL·HNO
3
with ammine complexes of cadmium(II) halides (Cl, Br, I) and zinc(II) chloride has been investigated under self-controlled reaction conditions. The complexes have been characterized by X-ray diffraction, FT-IR spectroscopy, thermal analysis and quantum chemical calculations. In the case of cadmium bromide and iodide salts, isostructural complexes with composition of CdX
2(HL)
2 were formed. With CdCl
2 a binuclear octahedral Cd
2(HL)
4(μ-Cl)
2(NO
3)
2 complex is obtained. Zinc(II) chloride with
HL·HNO
3
gives Zn(HL)
2ClNO
3, the zinc center exhibiting severely distorted five-coordinate stereochemistry, intermediate between an ideal trigonal bipyramid and a square pyramid. The course of complex formation as well as the thermal properties of the compounds has been explained using the HSAB principle. The assignment of the FT-IR spectra was supported by DFT computations.
Klasifikacija glavobolja bazira se na onoj koju postavlja Međunarodno udruženje za glavobolje (engl. International Headache Society). Zapravo se i razlikovanje migrene od drugih primarnih kao i ...sekundarnih glavobolja bazira na ovoj klasifikaciji, odnosno u oko 90 % slučajeva isključivo na temelju dobrih anamnestičkih podataka. Sukladno tome, neurološka obrada u velikom broju slučajeva nije potrebna. Problem ponekad predstavlja prisutnost više glavobolja istovremeno, promjene u karakteristici migrene, kao i glavobolje uslijed prekomjernog uzimanja lijekova, poglavito analgetika (GUPUL).
Synthetic paths toward the two polymorphs of a monohydrate, one anhydrous polymorph of 1-carboxamidino-5-hydroxy-3-methylpyrazole (
hcmp
) and two polymorphs of zinc complexes containing
hcmp
ligand ...are presented. By choosing ions which are not part of the final product, it is possible to direct the synthesis toward the particular polymorph. In all three modifications of
hcmp,
the same hydrogen bonding motif appears, leading to formation of similar molecular chains. Differences arise due to different modes of chain aggregation and the presence of solvent water. Analysis of the crystal packing and the energetic features of
hcmp
polymorphs is made using the PIXEL model. The thermal decomposition processes are examined using differential scanning calorimetry and thermogravimetry. Analysis of crystal packing in the two polymorphs of zinc complex suggests the key role of the hydrogen bonding capacity of the aqua ligand for the appearance of the two polymorphic forms. In both polymorphs of zinc complex, stacking interactions have an important role. However, the enhanced hydrogen bonding capacity of the aqua ligand influences the formation of multistacking arrangement.
Inflation is one of the phenomena that attract the attention of many researchers. Inflation is not a phenomenon that has appeared in recent years, from the time of creation of money and the ...development of the first economies. Today, although there are a large number of papers on this topic, we still do not know enough about all the factors that affect the formation and evolution of inflation and inflation dynamics. Regression analysis is a powerful statistical tool that can help you gain a large amount of existing data on inflation analysis and thus to partial answers to the questions that are all factors that affect inflation and in what way. In this paper, the use of multiple regression analysis was performed to analyze the influence of factors that contribute to the emergence of inflation, such as monetary aggregates, discount rate and the level of gross domestic product, the discount rate of the Central Bank of Serbia. It is also an analysis of the coefficients of price elasticity of money in the long run, the coefficient of price elasticity of production in the long term and elasticity of demand for money in Serbia.
The mechanistic details of oxygen atom transfer from Tp
RMoO
2(XPh) to PMe
3 were investigated for R
=
3-
iPr and 3-Me and X
=
O and S by density functional theory (DFT) calculations. The transition ...state exhibits a hypervalent structure at P and is both lower in energy and later, in contrast to the Hammond postulate.
Catalytic oxygen atom transfer (OAT), which frequently employs molybdenum oxo species, is an important reaction for both nature and industry. The mechanistic details of oxygen atom transfer from Tp
RMoO
2(XPh) to PMe
3 were investigated for R
=
3-
iPr and 3-Me and X
=
O and S by density functional theory (DFT) calculations of the enthalpies, free energy with solvent corrections, and natural bond orbital (NBO) analysis. The mechanism for both systems proceeds via rate-determining attack of PMe
3 to form a stable intermediate with a bound OPMe
3 ligand. From this intermediate the reaction proceeds through a substitution involving loss of OPMe
3 and coordination of a single CH
3CN solvent molecule. The solvent corrected free energy barriers of the rate-determining OAT step for the O and S systems were found to be energetically more favorable for the S systems by 6.2 and 2.2
kcal/mol (for the R
=
3-
iPr and 3-Me, respectively). This lower energy barrier is the result of better stabilization by the SPh ligand of the Mo
IV products and the transition states, which are the unexpectedly later and more product-like. Additional examination of the NBO analysis emphasizes the role of the local acidity of the Mo and by extension the character of the ligands. The decreased electronegativity and softer character of the S atom result in an increased covalent character in the Mo–X bond which leads to the stabilization of a later (and lower energy) transition state and the corresponding product of the S system relative to O system.
In order to find out whether metal type influences the stacking interactions of phenyl rings in square-planar complexes, geometrical parameters for Cu, Ni, Pd and Pt complexes, with and without ...chelate rings, were analyzed and compared. By searching the Cambridge Structural Database, 220 structures with Cu complexes, 211 with Ni complexes, 285 with Pd complexes, and 220 with Pt complexes were found. The results show that the chelate ring has a tendency to make the stacking interaction with the phenyl ring independent of metal type in the chelate ring. However, there are some differences among metals for complexes without a chelate ring. There are a number of structures containing Pd and Pt complexes, without chelate rings, that have short carbon-metal distances and parallel orientations of the phenyl ring with respect to the coordination plane. It was found that some of these complexes have a common fragment, CN, as a part of the ligands. This indicates that the CN supports stacking interactions of square planar complexes with the phenyl ring.
The mass media has a powerful impact on public attitudes about mental health and psychiatry. The question of identity of psychiatry as a medical profession as well as of the future of psychiatry has ...been the subject of much controversial discussion. Psychiatry today has the historical opportunity to shape the future of mental health care, medicine and society. It has gained in scientific and professional status by the tremendous increase of knowledge and treatment skills. Psychiatry should build up new transdisciplinary and integrative image of a specialized profession, promote it and make it public. Good public relations are very important for the future of psychiatry.
The crystal and molecular structure of Cu(
ampf
)(ClO
4
)(MeOH)
2
ClO
4
, (
1
),
ampf
=
N
,
N
′-bis(4-acetyl-5-methylpyrazol-3-yl)formamidine, determined by X-ray crystallography is described and ...compared with the structurally related copper(II) complexes, formed under similar experimental conditions, using Cu
II
salts with different anions. The complex formation is discussed in view of the structures of cobalt(II) and nickel(II) complexes with the same organic ligand and different anions, also formed under similar reaction conditions. Solvent molecules coordinated to the central atom play an important role in biologic systems. To get a better insight into the desolvation mechanism, in this study the desolvation pattern of
1
is presented. As in literature little attention is paid to the desolvation mechanism of solvate complexes, the desolvation mechanism of three, potentially biologically active isostructural pairs of octahedral Ni
II
and Co
II
compounds with
ampf
and
dmpc
(3,5-dimethyl-1
H
-pyrazole-1-carboxamidine) ligands are evaluated and compared with the desolvation of
1
. The results of the thermal data are discussed on the basis of structural features of the compounds. The minor differences in structures of the related compounds cannot be straightforwardly connected with the different solvent evaporation mechanism. To explain the differences found in desolvation pattern in isostructural Co
II
and Ni
II
complexes the Jahn-Teller effect is proposed.
The diimine-dioxime ligand, 4,9-diaza-3,10-diethyl-3,9-dodecadiene-2,11-dione
bisoxime (LH2), containing a N4 donor set was prepared by Schiff base
condensation of 2-hydroxyimino-3-pentanone and ...1,4-diaminobutane in two
ways: in protic and in aprotic solvent. Higher yield of (LH2) imine was
obtained when the synthesis was carried out using protic solvent (C2H5OH)
instead of aprotic benzene (78% and 30%, respectively). Cu(II) metal complex
of diimine-dioxime was synthesized in CH3OH from metal salt and LH2 in mole
ratio 1:1. The isolated complex was characterized by the elemental analysis,
IR spectroscopy and cyclic voltammetry. The structure of Cu2(LH)2?(ClO4)2
was determined by the single-crystal X-ray diffraction analysis. Comparison
with the structurally related diimine-dioxime Cu(II) complexes revealed the
influence of the weak Cu???O(perchlorate) interaction on the geometry of the
metallocycle.
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