Kinetics of the Dissociation of Cu2+ and Co2+ Complexes of Nitro Derivatives of 5,15-Diphenyl-3,7,13,17-tetramethyl-2,8,12,18-tetraethylporphyrin in Proton-Donor Media

Russian Journal of General Chemistry - Copper and cobalt complexes of nitro derivatives of planar and nonplanar derivatives of 5,15-diphenyl- 3,7,13,17-tetramethyl-2,8,12,18-tetraethylporphyrin are...     

Volume Properties of the H2O-DMF Mixture at the Pressure 0.101 MPa in the Temperature Range 278.15-323.15 K

The density of the water-N,N-dimethylformamide mixture throughout the entire range of compositions in the temperature range 278.15-323.15 K at atmospheric pressure (0.101 MPa) was measured. The coefficients of thermal dilatation were calculated. The value strongly depends on the composition of the mixture in the range 0 < X <: 0.3 (X is the molar fraction of dimethylformamide), which is associated with breakdown of water structure. An equation relating the molar volume of the water-dimethylformamide mixture to the composition of the mixture and to the temperature was proposed.     

Bound exciton in CuGaS2

In CuGaS₂ crystals absorption and luminescence spectra at the temperature 9 K at excitation by different wavelengths of Ar laser are investigated. A series of lines available in luminescence and absorption spectra is found. Another series of lines is found only in absorption spectra. The found series of lines of absorption and luminescence are determined by excitons bound on neutral acceptor. A model of electron transitions between the energy levels of the exciton bound on neutral acceptor is proposed.     

Electrophilic substitution in <Emphasis Type="Italic">meso</Emphasis>-phenylporphyrins

Electrophilic substitution reactions in the meso-phenylporphyrins are described. The relative reactivity of the various positions of the porphyrin cycle to attack by electrophiles was discussed.     

Synthesis of water-soluble copolymers containing porphyrin fragments in the side chain

The methods for the synthesis of water-soluble copolymers having porphyrin units in the side chain are described. Molecular-mass characteristics of the copolymers and mole content of porphyrin in copolymers are determined.     

Synthesis of tetraphenylporphins with reactive groups in the phenyl rings. 7.* salts of tetrakis(N,N,N-trimethylaminophenyl)porphins

Tetrakis(N,N-dimethylaminophenyl)porphins and water-soluble salts of tetrakis(N,N,N-trimethylaminophenyl)porphins have been obtained by the alkylation of tetrakis(aminophenyl)porphins with methyl iodide.For Communication 6, see [1].Ivanovo State Institute of Chemical Technology, Ivanovo Center 153460. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 668–671, May, 1996. Original article submitted December 6, 1995.     

Study of Extra Coordination of Bromo-Substituted Porphyrins to Organic Bases

Extra coordination of zinc complexes of bromo-substituted tetraphenylporphyrins was studied by spectrophotometry. It was found that the stability of complexes thus formed markedly increases upon -bromo-substitution in tetraphenylporphine. The effects of electronic and structural factors on the extra coordination were discussed. The stability constants of complexes formed by zinc porphyrins with organic bases were calculated, and the electronic absorption spectra of porphyrins in toluene and in other organic solvents were studied.     

Amination of <Emphasis Type="Italic">meso</Emphasis>-bromophenyl(polyalkyl)porphyrins: Synthesis of porphyrins containing a hydroxypiperidine fragment

5,15-Bis(4-bromophenyl)-2,8,12,18-tetraethyl-3,7,13,17-tetramethylporphyrin and 5-(4-bromophenyl)-13,17-dibutyl-2,3,7,8,12,18-hexamethylporphyrin were synthesized, and their palladium-catalyzed amination with a number of cyclic secondary amines, including hydroxypiperidines, was studied [Pd(OAc)₂, ligand, THF or dioxane, t-BuONa, 80–100°C]. The reactions of the meso-bromophenylporphyrins with piperidine and morpholine gave the corresponding amination products in quantitative yield. The amination with hydroxypiperidines required excess amine (3 equiv per bromine atom) and excess base (6–8 equiv) and was accompanied by formation of hydrodebromination products; in the reactions with the bis(bromophenyl)derivative, mixed products resulting from amination at one phenyl group and reductive debromination at the other were also formed. The yields of the amination products varied from good {75–50% in the reactions with 4-hydroxypiperidine and trans-3-hydroxy-4-[4-(2-fluorophenyl)piperazin-1-yl]piperidine} to moderate (20–50%, 3-hydroxypiperidine) and poor [11–25%, trans-3,4-dihydroxypiperidine and trans-3-hydroxy-4-(4-hydroxypiperidin-1-yl)piperidine].     

Interference of resonance luminescence of exciton polaritons in CuGaS2 crystals

The nonmodulated and wavelength-modulated reflection spectra of CuGaS₂ crystals for the polarization EIIc of 10 K are studied. The states n = 1, 2 and 3 of the excitons Γ₄ (A-excitons) and n = 1, n = 2 of B- and C-excitons are found. The nonmodulated absorption spectra for the polarization E⊥c at 10 K have been studied. The states n = 1, 2 and 3 of Γ₅ excitons are found. The main parameters of the A (Γ₄, Γ₅) and B, C exciton series at the energies of the longitudinal and transverse excitons Γ₄ for the states n = 1 and n = 2, the effective masses of electrons and holes are determined. The photoluminescence peaks were observed at n = 3 and n = 4 of the excitons Γ₅ in the luminescence spectra excited by the line 4880 Å of Ar⁺ laser. In the luminescence spectra the interference is found.     

Vibrational and Polariton Spectra of CdGa2S4 and CdAl2S4 Crystals

In this work the vibrational and polariton optical spectra of the CdGa₂S₄ and CdAl₂S₄ crystals grown from vapor phase and by the Bridgman method have been investigated. The light scattering by polaritons excited of various wavelength of Ar⁺ and He‐Ne lasers is studied.