- Magnetic properties and stability of negatively charged doubly bonded C1202- dimers
-
A new ionic complex {(MDABCO+)·ZnIITMPP} 2·(C1202-)·(C6H 4Cl2)2.15·(C6H 5CN)1.85 (1) (ZnIITMPP: zinc(ii) tetrakis(4-methoxyphenyl)porphyrin; MDABCO+: the cation of N-methyldiazabicyclooctane) has been obtained as single crystals. The complex contains negatively charged doubly bonded C1202- dimers whose magnetic properties have been studied. Magnetic moment of the complex is 2.69 μB at 290 K indicating presence of about two spins per dimer. The dimers show narrow doublet-like EPR signal with gM = 2.0014 and the linewidth of 0.315 mT at 290 K. The data of SQUID measurements for 1 can be fitted according to the Heisenberg model for isolated antiferromagnetically interacting spin pairs with exchange interaction of J/kB = -44.7 K. The EPR signal from the dimers and magnetic susceptibility of 1 decrease below 40 K resulting in diamagnetic dilution of the sample and the appearance of triplet features of the signal. Two pairs of lines show peak separation of 5.2 and 2.6 mT and are centered at gT = 2.0008. Averaged separation of 10.2 A between two spins was estimated. Additional narrow doublet-like signal is manifested at 40 K and below. The signal was centered at gI = 1.9984 (20 K) and was attributed to the impurity of non-dimerized C 60- since its intensity did not exceed 4% from that of the signal from the dimers. Heating of 1 above 380 K resulted in irreversible dissociation of the C1202- dimers to monomeric C 60- which was accompanied by transition from narrow to broad EPR signal. The degree of dimer-monomer conversion was 97.5% at 446 K.
- Konarev, Dmitri V.,Khasanov, Salavat S.,Otsuka, Akihiro,Yamochi, Hideki,Saito, Gunzi,Lyubovskaya, Rimma N.
-
-
Read Online
- Novel Axially Ligated Complexes of Zn(II)Porphyrin: Spectroscopic, Computational, and Antibiological Characterization
-
Abstract: The complexes of Zn(II)porphyrin with phenols (X) and pyridines (X') as the axial ligands in 1 : 1 molar ratio have been synthesized and characterized by elemental analysis and IR, UV-Vis, and 1H NMR spectroscopies. The fluorescence s
- Sujata Kundan,Bajju, Gauri D.,Gupta, Deepmala,Roy, Tapta Kanchan
-
-
Read Online
- Strength of the Zn-N coordination bond in zinc porphyrins on the basis of experimental thermochemistry
-
The compound, 5,10,5,20-tetrakis(4-methoxyphenyl)porphine zinc(II) (ZnTMPP), was prepared, and its thermochemical properties were experimentally established. The standard molar energy of combustion (ΔcU° m) was determined from oxygen rotating-bomb combustion calorimetry experiments. The standard molar enthalpies of combustion (Δ cH°m) and formation (ΔfH° m) were derived. The enthalpy of sublimation (Δ crgH°m) was determined by Knudsen effusion at high temperatures. With these results, the standard molar enthalpies of formation and atomization (ΔatH°m) in the gas state were calculated. A summary of the results at T = 298.15 K (p° = 0.1 MPa) is shown in Table 1. Using these results and those previously obtained for the free ligand, 5,10,15,20-tetrakis(4-methoxyphenyl)porphine, the mean dissociation enthalpy for the Zn-N coordination bond is obtained as D(Zn-N) = (160 ± 9) kJ-mol-1. This value is consistent with the results obtained using the same experimental approach in a similar system (5,10,15,20-tetraphenylporphine, TPP/ZnTPP) reported elsewhere. A discussion of the strength for the Zn-N coordination bond is made in terms of the structural and electronic features of the molecules involved.
- Patino, Rodrigo,Campos, Myriam,Torres, Luis Alfonso
-
-
Read Online
- A preparing method of p-nitroacetophenone
-
A preparing method of p-nitroacetophenone is disclosed. The method includes reacting p-nitroethylbenzene, as a raw material, in an autoclave at 110-150 DGE C for 3-7 h under the function of a metalloporphyrin catalyst shown as a formula 1 or a formula 2 in an oxygen atmosphere having a pressure of 0.8-2 MPa under a condition of no solvent; and subjecting an obtained reaction liquid mixture to after-treatment to obtain the target product that is p-nitroacetophenone. The method includes reaction in the sealed autoclave, thus greatly reducing volatilization loss of the raw material, and avoidingemission of reaction waste gas so as to avoid environment pollution therefrom. The bionic metalloporphyrin catalyst which is naturally degradable is adopted as an auxiliary catalyst, is low in dosage,and can increase product selectivity. Consumption of an organic solvent and purification of the target product are avoided, thus reducing the cost.
- -
-
Paragraph 0069-0071
(2019/01/07)
-
- Four aryl metal porphyrin process for the continuous production of
-
The invention discloses a continuous production process of tetraaryl metal porphyrin. The process is as follows: firstly, adding a solvent into a multi-phase reaction separation synchronous reactor, wherein the reactor comprises a stirring reaction tower with a reflux device, and at least two constant-temperature settling towers communicated with the bottom of the stirring reaction tower, and the stirring reaction tower comprises a gas-phase region and a reaction region; during reaction, filling the solvent in the reaction region and the constant-temperature settling towers, adding the reaction material tetraaryl porphyrin and a metal salt into the stirring reaction tower for stirring when a temperature is increased to reach a reflux temperature of the solvent or reacting under the condition of ventilating air, directly settling the tetraaryl metal porphyrin generated by the reaction under gravity action to enter the constant-temperature settling towers until the constant-temperature settling tower is filled up with the tetraaryl metal porphyrin, switching the stirring reaction tower to communicate with the other constant-temperature settling tower filled with the solvent and carrying out the process alternatively to realize continuous production. The continuous production process disclosed by the invention can continuously produce high-purity tetraaryl metal porphin with high yield and low cost.
- -
-
Paragraph 0050-0054
(2016/12/12)
-
- ORGANIC DYE COMPLEX AND MANUFACTURING METHOD THEREFOR
-
PROBLEM TO BE SOLVED: To provide an organic dye complex having a wider area of absorption wavelengths, especially a wider area of absorption wavelengths in a near-infrared region. SOLUTION: There is provided a composite of a specific phthalocyanine derivative and a porphyrin derivative having a structure of the formula (2). In the formula (2), A, B, C and D represent each independently a hydrogen atom, a halogen atom or a monovalent organic group, at least two of the A to D are substituted or unsubstituted aryl or substituted or unsubstituted heteroaryl, M2 represents at least one atom or atom group that may bind with porphyrin. COPYRIGHT: (C)2015,JPO&INPIT
- -
-
Paragraph 0201-0203
(2018/10/03)
-
- A novel and facile Zn-mediated intramolecular five-membered cyclization of β-tetraarylporphyrin radicals from β-bromotetraarylporphyrins
-
A novel and facile method for the Zn-mediated intramolecular cyclization of β-porphyrin radicals has been developed for the convenient and effective construction of newly fused five-membered porphyrin systems from readily available β-bromotetraarylporphyr
- Shen, Dong-Mei,Liu, Chao,Chen, Qing-Yun
-
p. 4982 - 4984
(2007/10/03)
-
- CHEMICAL DEGRADATION OF GAS-SENSING MESO-TETRA-ARYLPORPHIN THIN FILMS BY HIGH LEVELS OF DINITROGEN TETROXIDE.
-
Thin solid films of free base meso-tetra-arylporphins and their zinc, copper, platinum and palladium complexes have been exposed to high levels of dinitrogen tetroxide (NOX). The optical spectra (300-850 nm) were recorded in transmission before and after
- Honeybourne, Colin L.,Hill, Callum A. S.
-
p. 315 - 322
(2008/10/08)
-