E. V. Baranov

Terbium-containing copolymers based on the norbornene functional derivatives. Synthesis, photoluminescent and electroluminescent properties

New carbazole- and terpyridine- containing norbornene derivatives were synthesized and structurally characterized. On the basis of these compounds by the method of metathesis polymerization copolymers were obtained with carbazole and terpyridine fragments in side chains. The synthesized copolymers react with terbium pyrazolonate complex to form the terbium-containing polymeric materials exhibiting the metalcentered photo- and electroluminescence.

Synthesis and structure of triphenylantinony dimethacrylate

Triphenylantinony dimethacrylate Ph3Sb(O2CMe=CH2)2 was obtained in the reaction of triphenylantimony with methacrylic acid in the presence of hydrogen peroxide. The structure of the product was confirmed by elemental analysis, IR and 1H NMR spectroscopy. According to X-ray diffraction analysis the substance is a trigonal bipyramidal complex of antimony with three phenyl groups in its basis and two methacrylate groups at the bipyramid vertices.

Anhydrous mono- and dinuclear tris(quinolinolate) complexes of scandium: the missing structures of rare earth metal 8-quinolinolates

The first monomeric anhydrous scandium tris(8-quinolinolate) complex 1 with the 2-amino-8-quinolinolate ligands and the Sc(2)Q(6) dinuclear complex 2 with the unsubstituted 8-quinolinolate ligands have been synthesized and characterized by X-ray analysis and DFT calculations. The intramolecular hydrogen bonds appear to be responsible for the unique monomeric structure of complex 1. The DFT-based analysis of the electron density topology reveals the (3,-1) critical points corresponding to the O···H and N···H bonds. The two scandium atoms in compound 2 are inequivalent due to different ligand surroundings. They are coordinated by seven (5O, 2N) and eight (4O, 4N) ligand atoms. The increase in the coordination number is accompanied by a decrease in the positive charge of the metal atom as evidenced by the DFT calculations.

Novel germanium(IV) catecholate complexes

The interaction of germanium(II) chloride dioxanate with 3,6-di-tert-butyl-o-benzoquinone or with its mono-and dianion derivatives is attended by the redox transformations. The novel germanium bis-catecholate complexes were synthesized that contained coordinated ether molecules (THF (I), Et2O (II)) irrespective of the initial redox form of o-quinone. The germanium complex was also synthesized by the exchange reaction between GeCl4 and sodium catecholate. Complexes (I), (II) were characterized by NMR and IR spectroscopies, elemental and X-ray diffraction analyses.

Cyclometallated Iridium(III) Complex with 2-(Benzo(b)thiophen-2- yl)pyridyl and Norbornene-Substituted Pyrazolonate Ligands and Related Electroluminescent Red Light-Emitting Polymers

New cyclometallated iridium(III) complex, (NBEpz)Ir(Btp)2 (I) (NBEpzH is 1-phenyl-3-methyl-4-(5-bicyclo[2.2.1]hept-5-en-2-yl)-5-pyrazolone, and BtpH is 2-(benzo[b]thiophen-2-yl)pyridine), is synthesized. The structure of the compound is determined by X-ray diffraction analysis (CIF file CCDC no. 1406737). Copolymers with the carbazole and iridium-containing fragments in the side chains (P1–P3) are prepared from monomer I using the ROMP method (ROMP is Ring-Opening Metathesis Polymerization). Their photoluminescence and electroluminescence properties are studied. Copolymers P1–P3 exhibit an intense photoluminescence and electroluminescence of red color. The maximum current efficiency (17.9 cd/A) and power efficiency (9.1 lm/W) are reached using emitter P2.

Iridium-containing polymers based on functionalized norbornenes as new efficient electroluminophores

The copolymer with carbazole and iridium-containing groups in the side chains (P1) and the terpolymer with additional organosilicon units (P2) were synthesized by the ring-opening metathesis polymerization (ROMP). The photoluminescence (PL) and electroluminescence (EL) properties of the synthesized polymeric materials were investigated. The iridium-containing terpolymer exhibited the most efficient EL characteristics: the maximum brightness is 1780 cd m−2 (21 V), the maximum current efficiency is 23.3 cd A−1 (13 V), and the maximum power efficiency is 6.4 lm W−1 (11 V). The color coordinates of the emission in the CIE (Commision Internationale de l’Eclairage) diagram (0.21, 0.71) correspond to the green color and remain virtually unchanged in the whole driving voltage range.

Synthesis and structure of Schiff bases based on 4,6-di-tert-butyl-2,3-dihydroxybenzaldehyde. New sterically hindered bis-catecholaldimines

A reaction of 4,6-di-tert-butyl-2,3-dihydroxybenzaldehyde with aliphatic (ethylenediamine, propylene-1,3-diamine, 1,4-diaminobutane) and aromatic (o-, m-, p-phenylenediamines, 1,8-diaminonaphthalene, benzidine) diamines leads to the Schiff bases containing fragments of sterically hindered catechols in high yields (up to 97%). The products exist in two tautomeric forms in solutions and in the crystalline state. In the case of aliphatic diamines, catecholaldimines exist in solutions in the quinomethide form, whereas in the case of aromatic, in the catechol form. In the crystalline state, the position of the hydrogen atom in the O-H…N fragment is also affected by the intermolecular hydrogen bonds, which promote stabilization of the quinomethide form of catecholaldimines.

Preparation of amorphous water-soluble complexes of biometals with (1-hydroxyethylidene)diphosphonic acid, 2-aminoethanol, and 2-amino-2-(hydroxymethyl)propane-1,3-diol

Multifold enhancement of solubility in water of Fe(III) and Mn(II) complexes with (1-hydroxyethylidene) diphosphonic acid has been achieved by their transformation into the corresponding salts via interaction of aqueous suspensions of the poorly soluble complexes with 2-aminoethanol and 2-amino-2-(hydroxymethyl)propane-1,3-diol. Molecular structure of tris(2-hydroxyethanaminium)(1-hydroxyethylidene)-diphosphonate has been determined. Potential agricultural efficiency of the prepared iron and manganese derivatives as well as zinc and copper complexes with (1-hydroxyethylidene)diphosphonic acid as a microfertilizer has been estimated.

Synthesis, structure, and thermolysis of (fullerene)(toluene)dicarbonylchromium

Fullerene C 60 has 30 essentially localized double bonds and can form η 2 complexes with transition metals. Molybdenum and tungsten π complexes of dihaptocoordinated fullerene with different ligands, such as CO, phenanthroline, α , α -dipyridyl, triphenylphosphine, and maleic and fumaric acid esters, have been prepared and structurally characterized [1–4]. The η 2 -C 60 complex with the (diphosphine)tricarbonylchromium moiety has been characterized by spectral methods [5]. As is known, (arene)tricarbonylchromium complexes can exchange the CO group for alkenes when exposed to UV irradiation [6]. Therefore, we studied the interaction of C 60 with (toluene)tricarbonylchromium under UV irradiation.

Cyclometallated iridium(III) complex with 2-(2,4-difluorophenyl)pyridyl and norbornene-substituted pyrazolonate ligands and related electroluminescent polymers

New cyclometallated iridium(III) complex, NBEPzIr(Dfppy)2 · 2CH2Cl2 (I) (NBEPzH is 1-phenyl-3-methyl-4-(5-bicyclo[2.2.1]hept-5-en-2-yl)-5-pyrazolone, and DfppyH is 2-(2,4-difluorophenyl)pyridine), is synthesized and structurally characterized. Copolymers with carbazole and iridium-containing fragments in side chains (P1–P4) are obtained from monomer I by the ROMP method (ROMP is Ring-Opening Metathesis Polymerization). Their photoluminescence and electroluminescence properties are studied. Copolymers P1–P4 exhibit the green electroluminescence. The maximum current efficiency (2.60 cd/A) and power efficiency (0.63 Lm/W) are reached using emitter P3.