Yuliya G. Gorbunova

Supramolecular systems constructed from Crownphthalocyaninates

A review of coordination compounds of several metals (Co2+, Ru2+, Zn2+, Al3+, Y3+, Ln3+ = La, Gd, Yb, Lu) with tetra-crown-substituted phthalocyanine H2R4Pc (R4Pc2− = [4,5,4′,5′,4′′,5′′,4′′′,5′′′-tetrakis(1,4,7,10,13-pentaoxotridecamethylen)phthalocyaninate-ion]) has been presented. The syntheses of compounds with a given tetra-azamacrocyclic ligand are described. The template method based on the crown-substituted phthalodinitrile is the optimum technique for preparation of Ru2+ monophthalocyaninate and sandwich complexes of Lu3+. For other rare earth metals the new synthetic approach based on the application of the H2R4Pc ligand has been suggested. Some aspects of supramolecular chemistry including cation-induced aggregation in solutions have been discussed for the compounds of this class.

Electrochemical and spectral properties of tris[tetra(15-crown-5)phthalocyaninato]dilutetium(III)

Tris[tetra(15-crown-5)phthalocyaninato]dilutetium(III) (R4Pc)3Lu2, whose structure had been confirmed earlier by X-ray analysis, was further examined by physicochemical studies. The redox properties of this complex were investigated by cyclic voltammetry. The spectroelectrochemical study of this compound has been performed for the first time. Based on the results obtained and analysis of literature data, an electrochemical criterion related to double- and triple-decker structure of lanthanide phthalocyanines has been proposed. IR and 1H NMR data are also reported.

Ruthenium(II) meso-tetra-(benzo-15-crown-5)-porphyrinates: synthesis and spectroscopic investigation

The synthesis of novel ruthenium(II) meso-tetra-(benzo-15-crown-5)-porphyrinates, meso-[(B15C5)4Por]Ru(CO)(MeOH) (1) and meso-[(B15C5)4Por]Ru(L)2 (2)-(4) (meso-[(B15C5)4Por]2-= 5,10,15,20-tetrakis-(benzo-15-crown-5)-porphyrinato-dianion; L = pyridine (py), pyrazine (pyz), 4,4′-bipyridyl (4,4′-bpy)), where CO and MeOH, or two N-donor ligands are axially coordinated to the central metal, are reported. The metalation of the free ligand performed by the reaction of Ru3(CO)12 with meso-[(B15C5)4Por]H2 in 1,2,4-trichlorobenzene (TCB, bp = 215°C), gives (1) in a high yield. The synthesis of (2)-(4) involves the decarbonylation of (1) with trimethylamine N-oxide ((CH3)3NO) in the presence of an excess of the N-donor ligand. The coordination of the axially bonded ligands is evidenced by different spectroscopic data.

Electrochemical Study of Tetra-15-Crown-5-Phthalocyanine and its Copper and Cobalt Complexes

The electrochemical behavior of tetra-15-crown-substituted phthalocyanine and its copper and cobalt complexes in solution have been studied by voltammetric techniques in wide range of potentials. It is established that the ligand undergoes an irreversible oxidation process, as well as its copper and cobalt complexes. The necessary correlations between electrochemical properties and structures of the ligand and its complexes are proposed.

Interfacial self-assembly of functional bilayer templates comprising porphyrin arrays and graphene oxide

Fabricating of solid-supported hybrid nanostructures remains a challenging problem because it is difficult to control all interfacial interactions influencing the structure and stability of these systems. The most widely used approach to solving this problem is a bottom-up assembly on the surface templates such as self-assembled monolayers (SAMs). Herein we suggest an alternative approach to tailoring solid surfaces by a formation of an interlayer anchoring the nanostructured film to the solid substrate. We formed a multifunctional bilayer template (MBT), comprising an adhesive monolayer of graphene oxide and a functional ordered monolayer of metal organic compound (Zinc-tetra(4-pyridyl)porphyrin) directing further bottom-up growth of the nanostructures. The one-step assembly of MBT proceeded spontaneously at the air/water interface and was monitored by an in-situ fiber optic absorption and fluorescence spectroscopy in a Langmuir trough. Dilatation surface rheology was applied to study the evolution of molecular organization of the monolayers upon adding the zinc ions, GO and their mixture into the subphase. The MBT templates were used for the assembly of porphyrin-based SURMOFs with two different structures. Our strategy makes it possible to assemble surface-anchored nanostructures avoiding the use of SAMs and it can be extended to other types of ultrathin hybrid systems.