Mn(III)-5-(4-nitrophenyl)-10,15,20-triphenylporphyrin and Mn(III)-5,10,15-tri-(4-nitrophenyl)-20-phenylporphyrin were synthesized using the reactions of complex formation of corresponding porphyrins and metal exchange of their Cd complexes with MnCl2 in dimethylformamide. Partial reduction of Mn(III) to Mn(II) is observed upon dissolution of manganese(III) complexes in dimethylformamide. When NaOH solid is added to a solution of dimethylformamide and in ethanolamine unstable Mn(II) porphyrins are formed. The photochemical stability and oxidative degradation of Mn(III)-porphyrins have been studied. The metal exchange reaction of asymmetricaly substituted Cd(II)-porphyrins with manganese chloride in dimethylformamide has been studied. The kinetic parameters of the reaction were calculated. The influence of substituends and the nature of the salt on the kinetic parameters of the metal exchange reaction was revealed. The synthesized compounds were identified by methods UV-Vis, IR, 1H NMR spectroscopy and mass spectrometry.

Mn(III)-5-(4-nitrophenyl)-10,15,20-triphenylporphyrin and Mn(III)-5,10,15-tri(4-nitrophenyl)-20-phenylporphyrin were synthesized by complex formation reactions of the specified porphyrins and by metal exchange of Cd porphyrin complexes with MnCl 2 in dimethylformamide. The products were identified by mass spectrometry and UV-Vis, IR, and 1 H NMR spectroscopy. Partial reduction of Mn(III) to Mn(II) takes place upon dissolution of manganese(III) complexes in DMF. The addition of solid NaOH to a solution in DMF or ethanolamine gives unstable Mn(II) porphyrins. The photochemical stability and oxidative degradation of Mn(III) porphyrins were studied in chloroform and in a chloroform–hydrogen peroxide mixture. The metal exchange reaction between asymmetrically substituted Cd(II) porphyrins and MnCl 2 in DMF was studied. The kinetic parameters of the reaction were calculated. The influence of substituents and the nature of the salt on the kinetic parameters of the metal exchange reaction was identified.

A number of metal-linked porphyrin oligomers of different structures were synthesized and their luminescent sensitivity to temperature was studied. Density functional theory (DFT) was used to geometrically optimize the resulting compounds structure. Coordination Sn(IV)-dipyridylporphyrin tetramers formed through the interaction of pyridyl fragments of the macrocycle with Pd(II) and Pt(II) cations, as well as the octamer assembled by coordination of pyridyl groups with Pd(II) cations and bis-chelate binding of bidentate ligands in the axial positions of Sn(IV)-porphyrins with the Cu(II) cation, were shown to exhibit fluorescent thermal sensitivity in the temperature range of 328–383 K in the region of 600–650 nm. In this section, the dependence of the fluorescence quantum yield (fluorescence intensity) with a temperature increase is a monotonic pseudolinear trend. The flare-up ranges from 1.5 to 4.5 times, depending on the structure of porphyrin oligomers. At temperatures above 383 K, all studied porphyrin assemblies obtained on the basis of Pd(II) exhibit a decrease in fluorescence intensity. At the same time, their structure is preserved. The porphyrin tetramer obtained from Pt(II) undergoes a structural rearrangement, transforming into a presumably cyclometalated organoplatinum compound that exhibits effective luminescence at 493 nm. The results obtained could be used for the development of new temperature-assisted optoelectronic devices such as sensors, molecular reactors and catalysts.

Octa(2,6-difluorophenyl)tetraazaporphyrinate magnesium(II) has been treated with 96% sulfuric acid to obtain octa(2,6-difluorophenyl)tetraazaporphyrin. Coordination reactions of octa(2,6-difluorophenyl)tetraazaporphyrin and metal exchange of its magnesium complex with copper and nickel salts in dimethylformamide have been studied. Cu(II) and Ni(II) complexes with octa(2,6-difluorophenyl)tetraazaporphyrin have been synthesized. The resulting compounds have been identified by electron absorption, IR and 1H NMR spectroscopy, and mass spectrometry. The structures of the synthesized compounds were optimized by the DFT method. The fluorescence quantum yields of the studied compounds have been determined.

By reactions of di(4-halophenyl)maleindinitriles with magnesium and zinc(II) acetates in boiling ethylene glycol, Mg(II)-octa-(4-chlorophenyl)tetraazaporphyrin, Mg(II)-octa-(4-fluorophenyl)-tetraazaporphyrin, Zn(II)-octa-(4-chlorophenyl)tetraazaporphyrin, and Zn(II)-octa-(4-fluorophenyl)tetraazaporphyrins were synthesized. The cyclomerization of diphenylmaleinitrile with zinc acetate in ethylene glycol resulted in Zn(II)-Octaphenyltetraazaporphyrin. The corresponding Cu(II) and Mn(III)-octaphenyltetraazaporphyrins were synthesized in dimethylformamide using the metal exchange reaction of halogen-substituted magnesium complexes with copper(II) and manganese(II) chlorides. The obtained compounds were identified by electron absorption, IR, and 1H NMR spectroscopy, and mass spectrometry. The photochemical stability of the synthesized complexes was studied.

Triads L–SNP–L, containing two ligands, phenolphthalein or 1,3,5,7-tetramethyl-8-(4-hydroxyphenyl)-4,4-difluoro-4-boron-3a,4a-diazaindacene (BODIPY), axially bound to Sn(IV)octaethylporphyrinate, were synthesized. The sensitivity of the obtained triads to changes in the acidity of the medium has been studied. Photoexcitation of the BODIPY-SnP-BODIPY triad leads to photoinduced energy transfer from the BODIPY donor fragments to the porphyrinate acceptor. When the triad is excited at the wavelength λ exc = 490 nm, in addition to BODIPY fluorescence, fluorescence sensitized by the porphyrin fragment is recorded, and when the triad is excited at a wavelength λ exc = 400 nm, porphyrinate fluorescence flares up compared to initial SnP. In the triad with phenolphthalein molecules, the fluorescent properties of both the ligand and porphyrinate are quenched, however, sensitivity to changes in the solution pH increases.

Octa(2,6-difluorophenyl)tetraazaporphyrinate magnesium(II) has been treated with 96% sulfuric acid to obtain octa(2,6-difluorophenyl)tetraazaporphyrin. Coordination reactions of octa(2,6-difluorophenyl)tetraazaporphyrin and metal exchange of its magnesium complex with copper and nickel salts in dimethylformamide have been studied. Cu(II) and Ni(II) complexes with octa(2,6-difluorophenyl)tetraazaporphyrin have been synthesized. The resulting compounds have been identified by electron absorption, IR and 1 H NMR spectroscopy, and mass spectrometry. The structures of the synthesized compounds were optimized by the DFT method. The fluorescence quantum yields of the studied compounds have been determined.

A triad of two 1,3,5,7-tetramethyl-8-(4-hydroxyphenyl)BODIPY ligands (BODIPY) axially linked to Sn(IV)-octaethylporphyrin [Sn(BODIPY)(2)OEtP] is synthesized. The structure of the triad is optimized by quantum chemical calculations and confirmed by a combination of physicochemical methods. The spectral luminescent properties of the triad and its components in DMF solution are studied. Using a model system of the DMF-glycerol binary solvent, the sensitivity of the photophysical characteristics of the triad to the concentration-dependent viscosity of the solution, as well as to the addition of acids and alkalis, is studied. Sn(BODIPY)(2)OEtP photoexcitation leading to photoinduced energy transfer from donor fragments of BODIPY to the porphyrinate acceptor is observed. As a result, upon excitation of the triad at lambda(ex) = 490 nm both BODIPY fluorescence and porphyrin fluorescence are recorded. When the triad is excited at lambda(ex) = 400 nm, the fluorescence of the porphyrin increases compared to the initial Sn(IV)-octaethylpophyrin. This energy transfer, which depends on both the mobility of the medium and its acidity, provides the Sn(BODIPY)(2)OEtPtriad with the properties of a molecular rotor, a pH indicator and very high photostability (resistance to photobleaching), as well as antibacterial activity against the Staphylococcusaureus ATCC strain.

A comprehensive study of four classes of aromatic macroheterocycles - N-substituted, isomeric, contracted and inverted porphyrin analogues - was carried out using a combination of spectral and thermal, conductometric and quantum-chemical methods. It was shown that inverted porphyrinoids and meso-substituted corroles have a pronounced chemical activity of NH bonds, which is appeared in the ability of these compounds to interact with a weak electron donors B to form acid-basic molecular complexes like HnPn center dot B with unaccomplished proton transfer. It was concluded that the tendency of porphyrinoids to molecular complexation with electron donors is controlled by the combination of a few factors, as an increase in a K-system polarization of the molecule, a decrease in its aromaticity and an ability to form solvent-dependent tautomeric forms. It was demonstrated for the first time that the innercyclic NH-proton as part of molecular complex forms an intermolecular hydrogen bond with the electron-donor center of molecule B yielding unaccomplished acid-base interaction. NH-active forms of the inverted analog of porphyrin and corrole are formed in polar electron-donor media, for example, in N,N-dimethylformamide solutions. Molecular complexes formed under these conditions, similarly to 1 : 1 electrolytes, demonstrate concentration dependences of the enthalpy of dissolution, as well as a shift and broadening of proton NH signals in the H-1 NMR spectrum. However, they do not show a change in the specific electrical conductivity of the medium in comparison with a pure solvent. This indicates the presence of Hbound forms, rather than anionic particles in solutions of these porphyrinoids.

The electronic absorption spectra of cationic forms of porphyrinoids in acetonitrile or benzene with the addition of acetic or trifluoroacetic acid have been studied and the values of the acid-base interaction constants have been calculated. The order of changes in the basicity of the studied compounds obtained from spectrophotometric, quantum-chemical (DFT, B3LYP, and CC-pVDZ using NBO analysis), and thermodynamic data have been consistent.

Thermogravimetry and quantum chemistry, including NBO analysis, are used to study the thermal stability and NH acidity of single and double protonated forms of tetrapyrrole macroheterocyclic ligands (porphyrins, their inverted and N-substituted analogs, and corroles). The temperature ranges of the destruction of porphyrinium acetates and trifluoroacetates, the enthalpies of evaporation of acid molecules from the crystalline phase, and the composition of cationic salts are calculated. The structures of protonated forms of macrocycles are optimized. The energies of porphyrin–acid interaction and the values of charge transfer ​​during the formation of bonds are calculated.

Fluorescence and photostability against the action of UV irradiation of different porphyrins in benzene, DMF, and acetic acid media have been studied. The effect of the macroheterocycle structure on the conditions of its thermal decomposition under inert atmosphere has been investigated.

The effects of the macrocycle structure and the medium nature on photodecomposition of porphyrinoids under UV irradiation have been studied. The influence of protonation, nonplanar structure of the molecule, and reactivity of NH bonds on the photostability of porphyrins and their analogs has been shown.