Larisa G. Tomilova

Synthesis of 1,2-bis(3,4-dicyanophenoxymethyl)benzene and binuclear zinc phthalocyanines of clamshell and ball types

A novel 1,2-bis(3,4-dicyanophenoxymethyl)benzene was synthesized from 1,2-bis-(hydroxymethyl)benzene and 4-nitrophthalodinitrile. Its condensation with 4-tert-butylphthalodinitrile results in a binuclear phthalocyanine of clamshell type. Reaction of bisphthalodinitrile with a large excess of zinc acetate gives rise to a binuclear phthalocyanine of ball type (33% yield). The successful syntheses of these binuclear phthalocyanines were carried out by microwave irradiation and solid phase methods.

Electrocatalytic CO2 reduction in methanol catalyzed by mono-, di-, and electropolymerized phthalocyanine complexes

The electroreduction of CO2 was studied in methanol in the presence of mono- and diphthalocyanine complexes and phthalocyanine films prepared by electrochemical anodic polymerization. Methyl formate is the main reaction product of the reaction catalyzed by the mono- and diphthalocyanine complexes of rare-earth metals. Copper 2,9,16,23-tetra-tert-butylphthalocyanine allows the transformation of CO2 into methane in ∼30% yield. In the presence of both electropolymerized and graphite electrode-supported copper 2,9,16,23-tetraaminophthalocyanine, CO and methyl formate are the main reaction products.

Peripheral functionalisation of a stable phthalocyanine J-type dimer to control the aggregation behaviour and NLO properties: UV-Vis, fluorescence, DFT, TDHF and thermal study

This novel research opens the possibility of controlling the spectral, fluorescent and non-linear optical (NLO) properties of stable J-type phthalocyanine dimers. In our group, thermally and chemically stable supramolecular J-type dimers, based on low-symmetry phthalocyanine macrocycles, have been synthesised for the first time, and the present work is a fruitful continuation of the initiated studies. Using an example of a dimeric magnesium complex, consisting of the same anti-parallel oriented 2-hydroxy-9,10,16,17,23,24-hexabutylphthalocyanine macrocycles, we first demonstrated the ability of stable phthalocyanine J-dimers to undergo peripheral functionalisation. UV-Vis, fluorescence and DFT studies showed that when 2-(diethylphosphoryl)-4-methylpenta-1,3-dienyl-3-oxy-moieties are introduced into a dimer structure, the intermolecular association of large molecules varies significantly, tending to ordering. Simulation of the nonlinear optical properties with the TDHF/6-311++G** theoretical approximation has shown that the chemical alteration of a dimeric structure results in an increasing polarisability (α), first hyperpolarisability (β) and an angle θ(μ,βmax) between the dipole moment μ and the main direction of the charge-transfer transition βmax.

Synthesis of alkyl-substituted phosphorus phthalocyanines and triazatetrabenzocorroles

New alkyl-substituted phosphorus phthalocyanines and triazatetrabenzocorroles were synthesized. The structures of these complexes were confirmed by 1H, 13C, and 31P NMR spectroscopy, mass spectrometry, and electronic absorption spectroscopy.

A highly stable double-coordinated 2-hydroxy-tri(tert-butyl)-substituted zinc phthalocyanine dimer: synthesis, spectral study, thermal stability and electrochemical properties

A highly stable J-type dimer based on 2-hydroxy-tri(tert-butyl)-substituted zinc phthalocyanine with specific supramolecular architecture was investigated by UV-visible and fluorescence spectroscopy and by cyclic voltammetry to show strong π–π interactions and coordination between hydroxy-groups and Zn2+ central metal ions. The possibility of controlling the fluorescent properties of the obtained complex by using different solvents is demonstrated, which, along with the high thermal stability according to the thermoanalytical study, may increase practical applicability of supramolecular dimeric phthalocyanine compounds.

Bis(tetrabenzotriazaporphyrinato) and (tetrabenzotriazaporphyrinato)(phthalocyaninato) lutetium(III) complexes – novel sandwich-type tetrapyrrolic ligand based NIR absorbing electrochromes

The first sandwich-type complexes have been prepared for tetrabenzotriazaporphyrin ligands. The compounds reveal intrinsic UV-Vis/NIR absorption as well as peculiar electrochromic behavior. The heteroleptic (tetrabenzotriazaporphyrinato)(phthalocyaninato) lutetium derivative shows intermediate spectral and electrochemical properties with respect to homoleptic relatives.

Directed synthesis of bi- and polynuclear clamshell-type phthalocyanines and their physico-chemical investigations

Novel bi-, tri- and tetranuclear butyl- and tert-butyl-substituted clamshell-type phthalocyanines were synthesized starting from 2-hydroxyphthalocyanines with quantitative yields. The structures of the obtained compounds were characterized by a complex of NMR spectroscopy and mass spectrometry techniques. Applying electronic absorption spectroscopy (UV-vis) and density functional theory (DFT) showed the complicated conformation equilibria for the spacer-bonded macrocyclic compounds and led us to estimate their behavior dependent on the number and relative orientation of macrocycles.

Synthesis and spectral properties of new planar binuclear phthalocyanines sharing the benzene ring

New planar binuclear phthalocyanines sharing the benzene ring were synthesized and their spectral properties were studied. Intense absorption in the near-IR region (∼850 nm) was observed for the first time.

Study of the catalytic activity of electrochemically reduced forms of phthalocyanines in the reaction of CO2 with epoxides

Catalytic activity of electrochemically reduced forms of mono- and diphthalocyanine complexes of transition and rare-earth elements in the reaction of carbon dioxide with epoxides is considerably higher than that of corresponding neutral forms. The catalytic efficiency depends on the nature of the phthalocyanine complex, the method of the catalyst immobilization, and the electrophilicity of epoxide.

Electrochemical investigation of lanthanide octa-tert-butylsubstituted diphthalocyanine complexes in solutions. Approximation of their redox transitions by semiempirical calculations for yttrium diphthalocyanine

The electrochemical potentials of seven redox transitions for green forms and eight redox transitions for blue forms of neutral octa-tert-butylsubstituted diphthalocyanine cornplexes of lanthanides Pct2Ln (Ln=Pr, Sm, Dy, and Lu) in solutions were measured by cyclic voltammetry and rotating disc electrode techniques. The spectroelectrochemical investigation of the products of two-electron oxidation and reduction of the green form of Pct2Lu was performed. The frontier molecular orbitals, total charge densities, total spin densities, electrostatic potentials, and heats of ion formation for (Pc2Y)m+,n− (m=0, 1, 2 and 3;n=1, 2, 3 and 4), which can model the products of the redox transitions of the diphthalocyanines under study, were calculated using the semiempirical ZINDO/1 method. The calculations for (Pc2Y)m+,n− and absorption spectra show that the electron changes in all redox transitions of the green forms of Pct2Ln are mainly localized on the ligands.