Search

New cyclometalated iridium(III) complexes, NBEpicIr(Ppy)2 (I) and NBEpicIr(Dfppy)2 (II), were synthesized (NBEpicH = 3-(((1S,4S)-bicyclo[2.2.1]hept-5-ene-2-carbonyl)oxy)picolinic acid, PpyH = 2-phenylpyridine, DfppyH = 2-(2,4-difluorophenyl)pyridine). Complex I was characterized by X‑ray diffraction analysis (CIF file CCDC no. 1878882). Ring opening metathesis polymerization involving compounds I and II and carbazole norbornene monomers gave new iridium-containing copolymers. The photophysical properties of complexes I and II and copolymers based on them were studied.

New water-soluble polynorbornenes P1–P4 containing oligoether, amino acid groups and luminophoric complexes of iridium(III) were synthesized by ring-opening metathesis polymerization. The polymeric products in organic solvents and in water demonstrate intense photoluminescence in the red spectral region. The polymers P1 and P3 with 1-phenylisoquinoline cyclometalating ligands in iridium fragments reveal 4–6 fold higher emission quantum yields in solutions than those of P2 and P4 that contain iridium complexes with 1-(thien-2-yl)isoquinoline cyclometalating ligands. The emission parameters of P1–P4 in degassed solutions essentially differ from those in the aerated solutions showing oxygen-dependent quenching of phosphorescence. Biological testing of P1 and P3 demonstrates that the polymers do not penetrate into live cultured cancer cells and normal skin fibroblasts and do not possess cytotoxicity within the concentrations and time ranges reasonable for biological studies. In vivo, the polymers display longer phosphorescence lifetimes in mouse tumors than in muscle, as measured using phosphorescence lifetime imaging (PLIM), which correlates with tumor hypoxia. Therefore, preliminary evaluation of the synthesized polymers shows their suitability for noninvasive in vivo assessments of oxygen levels in biological tissues.

A new iridium(III) cyclometalated complex NBEpzIr(Tiq)2 {NBEpzH is 4-[(bicyclo[2.2.1]hept-5- en-2-yl)hydroxymethylidene]-5-methyl-2-phenyl-2,4-dihydro-3H-pyrazole-3-on and TiqH is 1-(thien-2-yl)isoquinoline} was synthesized. Copolymers with carbazole and iridium-containing fragments in side chains were obtained on the basis of the synthesized monomer by the method of ring-opening metathesis polymerization. The copolymers exhibit intense photoluminescence and electroluminescence of deep red color.

Copolymers with oligoether units and luminophoric iridium(III) complexes in the side chains have been synthesized via metathesis polymerization. The copolymers containing different luminophoric iridium(III) complexes have exhibited strong green, blue-green, or red photoluminescence. The copolymers are soluble in water, forming micelles with average size 14‒20 nm. The copolymer with red photoluminescence has low cytotoxicity with respect to epidermoid human carcinoma cells (line A431).

A new cyclometallated iridium(III) complex NBEpzIr(Piq)2 (I) (NBEpzH is 1-phenyl-3-methyl- 4-(5-bicyclo[2.2.1]hept-5-en-2-yl)-5-pyrazolone, PiqH is 1-phenylisoquinoline) is synthesized. The structure of the compound is determined by X-ray diffraction analysis (СIF file CCDC no. 1521037). Copolymers with the carbazole and iridium-containing fragments in the side chains (P1–P3) are prepared from monomer I by the ring-opening metathesis polymerization method. Their photoluminescence and electroluminescence properties are studied. Copolymers P1–P3 exhibit an intense photoluminescence and electroluminesce of red color. The maximum luminance (3010 cd/m2) and current efficiency (15.1 cd/A) are achieved for emitter P2.

New ionic binuclear complexes of iridium(III) containing 1,4-bis[2-(2-pyridyl)benzimidazolato]butane as a bridging ligand were synthesized. These compounds exhibit intensive photo- and electroluminescence of yellow-green, green-yellow, and pink colors. The maximal electroluminescence brightness was 4565 cd/m2.

New iridium(III) ionic binuclear complexes, in which iridium-containing cyclometallated fragments are bound by a bridging bisphenanthroline ligand were synthesized. The compounds obtained show intensive photoluminescence of yellow and yellow-green colors.

New copper(I) complexes with norbornene-substituted benzimidazole ligands were synthesized. On the base of the obtained compounds carbon-chain copper-containing copolymers possessing photo- and electroluminescent properties were obtained by the metathesis polymerization method. Polymeric emitters show electroluminescence of yellow and orange colors with a maximum brightness as high as 629 cd/m2.

New dinuclear copper(I) complexes with bridging bis-diimine ligands were synthesized on the basis of benzimidazole derivatives. The obtained complexes showed photo- and electroluminescent properties. Copper-containing emitters exhibited yellow, orange, and yellow–green electroluminescence with a maximum brightness of 1166 cd/m2.

A potassium derivative of 2-(pyridin-2-yl)-1H-benzo[d]imidazole (BenzimidK) is synthesized and structurally characterized (СIF file CCDC no. 1478559). The complex is used for the preparation of new bis(diimine) ligands containing different diimine fragments linked by the bridging (CH2)4 group.

Copolymers containing fragments of cholic acid and luminophore complexes of iridium(III) and copper(I) in the side chains have been synthesized by metathesis polymerization. Photophysical properties of the obtained compounds have been investigated. Iridium-containing copolymers demonstrate intense photoluminescence of green, bluish-green and red colors. Copper-containing copolymers generate radiation of green and yellow-green colors. The color of photoluminescence of the metal-containing polymers is determined by the nature of copper(I) and iridium(III) complexes bonded to polymer chain.

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.

Using the method of metathesis polymerization carbon-chain homopolymers containing triрhenylsilyl, tritolylsilyl and trithienylsilyl groups in the side chains, as well as their copolymers with additional carbazole-containing units have been synthesized. Photophysical properties of the obtained compounds were investigated. All polymer products show an intense photoluminescence in the blue region of the spectrum. The largest quantum yield (61.4%) was shown by the copolymer with triphenylsilyl and carbazole side groups.

New oxyquinoline boron complexes Mes2BQ (I) and Mes2BQMe (II), where QH is 8-hydroxyquinoline and QMeH is 2-methyl-8-hydroxyquinoline, (CIF files CCDC 1051351 (I) and 1051352 (II)) are synthesized and structurally characterized. Their photoluminescence (PL) and electroluminescence (EL) properties are studied. The compounds have an intense green PL. The EL characteristics of complexes I and II doped in poly-N-vinylcarbazole (PVK) differ substantially. Compound I generates green luminescence with a brightness of 356 cd/m2, whereas white EL with a brightness of 36 cd/m2 is observed in the case of compound II.

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.

New norbornene monomer, viz., 5-[(bicyclo[2.2.1]hept-5-en-2-ylmethoxy)methyl]-8-[(dimesitylboryl)oxy]quinoline (1), was synthesized. The copolymers based on monomer 1 and carbazole-containing norbornene derivatives were synthesized by ring-opening metathesis polymerization. The photoluminescent (PL) and electroluminescent (EL) properties of the synthesized polymeric products were studied. The copolymers revealed the green EL with a maximum luminance of 146 cd m–2. The dependences between the PL and EL efficiencies of the polymers and their structures were determined.

A new 4-acylpyrazolone—1-phenyl-3-methyl-4-(2,3,4,5,6-pentafluorobenzoyl)-1H-pyrazole-5(4H)-one (Pfb-PMPH)—was prepared in a high yield by the reaction of 1-phenyl-3-methylpyrazol-5-one with pentafluorobenzoyl chloride in the presence of calcium and barium hydroxides. On heating this compound in vacuum up to 170°C, elimination of HF takes place to give the intramolecular cyclization product, 1-phenyl-3-methyl-5,6,7,8-tetrafluorochromeno[2,3-c]pyrazol-4(1H)-one. The structures of Pfb-PMPH (HL1) and the cyclization product (L2) were determined by X-ray diffraction (CIF files CCDC nos. 1010331 (HL1), 1010332 (L2), 1010333 (VI), 1010334 (VII), 1010335 (VIII), 1010336 (IX), and 1010337 (X)). The reactions of Pfb-PMPH with lanthanide silylamides [(Me3Si)2N]3Ln in a THF solution give pyrazolonate complexes (Pfb-PMP)3Ln(THF) (Ln = Sm, Eu, Gd, Tb, Lu). The compounds react with Ph3PO to give the derivatives (Pfb-PMP)3Ln(OPPh3)2 · xEtOH, which were studied by X-ray diffraction. The synthesized lanthanide complexes are luminescent at room temperature and exhibit ligand- and metal-centered emission.

New copper(I) complexes with pyrazolonate ligands [Cu(Pr i -PMP)(DPEphos)] ( 1 ) and [Cu(Bu t -PMP)(DPEphos)] ( 2 ) (Pr i -PMP = 1-phenyl-3-methyl-4-isobutyryl-5-pyrazolonato, Bu t -PMP = 1-phenyl-3-methyl-(2,2-dimethylpropan-1-oyl)-5-pyrazolonato; DPEphos = bis[2-(diphenylphosphino)-pheny]ether) were synthesized and structurally characterized. An unusual η 1 coordination of pyrazolonate ligand to the copper atom was found in complex 2 . Photo- and electroluminescent properties of the synthesized compounds were investigated. In crystalline form compounds 1 and 2 revealed dual emission consisting of the bands at 445–450 and 485–488 nm which were assigned to transitions from the S 1 and T 1 states. DFT and TD DFT calculations as well as electrochemical studies correlate with the photophysical data. Synthesized copper(I) complexes generated electroluminescence of yellowish-orange ( 1 ) and yellow ( 2 ) colors with the maximum luminance of 286 and 39 cd/m 2 , respectively.

A cyclometallated platinum(II) complex with 2-(2,4-difluorophenyl)pyridinyl and norbornene-substituted pyrazolonate ligands (1) was synthesized. Based on monomer 1, the copolymers with carbazole and platinum-containing fragments in the side chains (P1, P2) and terpolymers with additional organosilicon units (P3, P4) were obtained by ring-opening metathesis polymerization (ROMP). Photoluminescent and electroluminescent properties of the synthesized polymers were investigated. Copolymer P1 exhibited green electroluminescence, and polymeric emitters P2—P4 generated white irradiation. The maximum current efficiency (15.69 cd A–1) and maximum power efficiency (2.17 lm W–1) were reached for emitter P3.

The data on the synthesis and physicochemical and photo- and electroluminescent properties of carbochain linear polymers containing ions of rare-earth metals bound via chemical or coordination bonds to the polymer chain are summarized. The effects of the ligand environment at lanthanide atoms and the structures of the polymers on their luminescence activity are considered. Possible approaches to increase the efficiency of electroluminescence of polymer lanthanide emitters are discussed.

The temperature dependences of the pressure of saturated vapor of pyrazolone complexes of rare-earth elements Ln(PMIP)3 (where Ln = Y, Ho, Er, Tm, Lu; PMIP = 1-phenyl-3-methyl-4-isobutyryl-5-pyrazolone) are studied via Knudsen effusion, and the enthalpy of their sublimation is determined. Mass spectra and differential scanning calorimetry data are obtained.

New terbium-containing copolymers were prepared by ring-opening metathesis copolymerization (ROMP) of norbornene substituted terbium complex Tb(L1)2(L2)(TPPO)2 (L1 = 1-phenyl-3-methyl-4-isobutyryl-5-pyrazolonato, L2 = 1-phenyl-3-methyl-4-(5-bicyclo[2.2.1]hept-5-en-2-yl)-5-pyrazolonato, TPPO = triphenylphosphine oxide) and carbazole-containing norbornene derivatives. The photoluminescence (PL) spectra of the copolymers contained strong narrow bands of terbium ion at 492 (5D4 → 7F6), 550 (5D4 → 7F6), 586 (5D4 → 7F4), 624 (5D4 → 7F3) nm and emission in the region of 350-450 nm assigned to copolymer matrixes. The electroluminescence (EL) spectrum of the tree-layer device of configuration of ITO/Tb-copolymer(40 nm)/BATH(30 nm)/Alq3(30 nm)/Yb revealed intense emission bands of Tb(III) ions and a broad band at ca. 520 nm of low intensity attributed to emission from triplet level of carbazole groups. The maximum luminance of 70 cd/m2 at 17.5 V, the maximum current efficiency of 0.56 cd/A at 11 V and the maximum power efficiency of 0.16 lm/w at 11 V were achieved. The CIE coordinates (0.28, 0.47) were corresponded to green color and independent on driving voltage.

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.

The sublimation of 1-phenyl-3-methyl-4-isobutyryl-5-pyrazolonate complexes of neodymium and terbium was studied by the Knudsen effusion method with mass spectrometric gas phase monitoring. The gas phase was shown to contain only monomeric molecular species. The sublimation enthalpy (kJ/mol) for Nd complex is 205.9 ± 2.7 and that for the Tb complex is 208.0 ± 4.0.

The reaction of carbazole with KOH in dimethylformamide (DMF) at 75°C for 1.5 h affords CarbK(DMF) (CarbH is carbazole) in 90% yield. The crystallization of the compound from DME, CH3CN, and CD3CN gives complexes CarbK(DME)2, CarbK(DMF)(CH3CN), and CarbK(DMF)(CD3CN), respectively, whose structures are determined by X-ray diffraction analyses. The dissolution of CarbK(DMF)(CH3CN) in CD3CN results in the deuterium exchange in the bound solvent to form complex CarbK(DMF)0.5(CD2HCN)1.5, whose structure is also established by X-ray diffraction analysis.

New cyclometallated iridium(III) complex (NBEpz)Ir(Ppy)2 · 2CH2Cl2 (I) (NBEpzH is 1-phenyl-3-methyl-4-(5-bicyclo[2.2.1]hept-5-en-2-yl)-5-pyrazolone, PpyH is 2-phenylpyridine) is synthesized and structurally characterized. Compound I undergoes metathesis polymerization and forms new iridium-containing copolymers. The photophysical properties of complex I and related copolymers are studied.

Lanthanide pyrazolonate complexes Ln(But-PMP)3 (Ln = Pr, Nd, Gd, Tb, Tm, and Lu) are synthesized by the reactions of 1-phenyl-3-methyl-4-(2,2-dimethylpropan-1-oyl)pyrazol-5-one (But-PMPH) with metallic lanthanides in the presence of catalytic amounts of the corresponding metal triiodides. The yields of the products are close to quantitative ones. The synthesized compounds can sublime in vacuo (10−3 Torr) in the temperature range from 235 to 270°C. X-ray diffraction analyses of the sublimed complexes show that they are dimers [Ln(But-PMP)3]2 (Ln = Gd, Tb, and Tm) in which metal atoms are linked by two bridging pyrazolonate fragments. The coordination environment of the lanthanide is a distorted one-capped trigonal prism.

New cyclometalated platinum(II) complexes with pyrazolonate ancillary ligand (ppy)Pt(pmip) (1) and (dfppy)Pt(pmip) (2) (ppy = 2-phenylpyridine, dfppy = (4,6-difluorophenyl)pyridine, Hpmip = 1-phenyl-3-methyl-4-isobutyryl-5-pyrazolone) were synthesized and structurally characterized. Both compounds revealed square-planar geometry. The crystal cell of 1 was found to contain the monomer molecules of platinum compound whereas dimer molecules of 2 with short Pt⋯Pt contacts of 3.2217(3) A were observed in the crystal cell of 2. Photophysical properties of 1 and 2 were investigated in detail. The highly resolved photoluminesence spectra of the platinum complexes in solution contain emission bands in the region of 470–550 nm attributed to monomer compounds 1 and 2. The triplet-state energies of 1 and 2 obtained from DFT calculations agree very well with the experimental data. In the crystalline state complex 2 revealed excimer emission as a structureless broad band at ca. 584 nm related to dimer molecules of platinum compound presented in the crystals.

New copper(I) complexes containing the norbornene-substituted phenanthroline ligand were synthesized. Based on these compounds, new carbon-chain copper-containing copolymers possessing the photo- and electroluminescent properties were obtained by the metathesis polymerization.

Functionalized polynorbornenes with terpyridine and carbazole groups in pendant chains were prepared by metathesis copolymerization. The polymeric products prepared react with europium thenoyltrifluoroacetonate to form new carbon-chain copolymers with different ratios of organic and europium-containing units. The polymeric materials prepared were characterized by IR and NMR spectroscopy, gel permeation chromatography, differential scanning calorimetry, and elemental analysis. All the europium-containing copolymers exhibit strong metal-centered photoluminescence in solution and in thin film.

New copolymers containing oxadiazole, carbazole, and europium-containing fragments in the side chains were synthesized by ring-opening metathesis polymerization. The polymeric materials obtained were characterized by IR spectroscopy, GPC and DSC methods, and elemental analysis. All the copolymers possess strong metal-centered photoluminescence in solution and in thin film. In the electroluminescence spectra, the emission of the europium cations is exhibited and a broad band with the maximum at 507 nm is observed, which supposedly is attributable to the emission of the electroplexes between the polymeric matrix and the europium-containing fragments.

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.

The new ruthenium(II) complex Ru(PMIP)2(PPh3)2 (HPMIP is 4-isobutyryl-3-methyl-1-phe-nylpyrazol-5-one) was obtained from RuCl2(PPh3)3 and Na(PMIP)(DME) (DME is dimethoxyethane). The structures of the complex obtained and the starting sodium pyrazolonate were determined by X-ray diffraction. The ruthenium pyrazolonate complex initiates metathetical norbornene polymerization producing high-molecular-weight polynorbornene in low yield.

Rare-earth pyrazolonates Ln(PMIP)3 (Ln = Y, Nd, Gd, Tb, Er, Tm, Lu) were synthesized in high yields by the reaction of 1-phenyl-3-methyl-4-isobutyryl-5-pyrazolone (HPMIP) with rare-earth metals in the presence of catalytic amount of LnI3. The isolated compounds were found to sublime in vacuum (10−3 Torr) in the temperature range of 230–265 °C. Single crystal X-ray analyses of the sublimed rare-earth complexes revealed dimmers [Ln(PMIP)3]2 (Ln = Y, Gd, Tb, Er, Tm) in which rare-earth metals are bridged by pyrazolonate units. The coordination environment of the metal atoms can be described as distorted monocapped trigonal prism.

A norbornene-containing ortho-quinone, 5-{5-(bicyclo[2.2.1]hept-2-enyl)hydroxymethyl)-3,6-ditert-butyl-o-benzoquinone, was synthesized by the nucleophilic addition of 5-(hydroxymethyl)bicyclo[2.2.1] hept-2-ene to 3,6-di-tert-butyl-o-benzoquinone. The structure of the compound was established by the X-ray analysis. The monomer obtained undergoes metathesis polymerization in the presence of Grubbs catalyst of the third generation with the formation of polynorbornene containing quinone fragments in the side chains.

Norbornene based monomers containing the 2-phenylpyridinato–N,C2′ platinum(II) complex bonded by acetylacetonate or pyrazolonate anchor groups were synthesized and copolymerized with a carbazole-containing norbornene comonomer by ring-opening metathesis polymerization (ROMP). The photo- and electroluminescence spectra of the resulting Pt-copolymers are similar. They consist of broad bands with maxima at 495, 530 and 565 nm which arise from the mixed ligand centered (LC) and metal to ligand charge transfer (MLCT) transitions. The copolymer with the cyclometalated platinum(II) complex bonded to the polymer chain via the pyrazolonate anchor group revealed the highest brightness of electroluminescence (260 cd/m2 at 21 V).

The heteroelement-containing alkylidene imide complexes with molybdenum and tungsten Et3SiCH=Mo(NAr)(OR)2 (I), Et3 ECH=W(NAr)(OR)2 (E = Si (II), Ge (III); Ar = 2,6-i-Pr2C6H3; R=CMe2 CF3) and π-complex (RO)2(ArN)Mo(CH2=CH-GeEt3) (IV) were synthesized by the reaction of Alkyl-CH=M(NAr) (OR)2 (M=Mo, W; Alkyl = t-Bu, PhMe2C) with organosilicon and organogermanium vinyl reagents Et3ECH=CH2 (E = Si, Ge). The structure of compounds I–III was determined by X-ray diffraction (XRD). The complexes I–IV are active initiators of metathesis polymerization of cycloolefins.

At the initial stages the polymerization of cis-cyclooctene in the bulk with the catalysts Me3C-CH=Mo(NAr)(OCMe2CP3)2, PhMe2C-CH=Mo(NAr)(OCMe2CP3)2, Me3Si-CH=Mo(NAr)(OCMe2CP3)2, and PhMe2Si-CH=Mo(NAr)(OCMe2CP3)2 predominantly affords cis-polyoctenamers. The content of the trans- units in the polymer increases with an increase in the conversion. The sharpest increase in the trans- unit content observed for conversions higher than 80% is related to secondary metathesis reactions. The number-average molecular weights of the polymers increase linearly with the conversion. At conversions above 80% the molecular weights decrease due to the increasing contribution of chain transfer reactions. Polyoctenamers with the increased content of trans- units crystallize in two modifications.

Bimetallic alkylidene complexes of molybdenum (RF3O)2(ArN)Mo CH–SiMe2–CH Mo(NAr)(ORF3)2 (1) and (RF3O)2(ArN)Mo CH–SiPhVin–CH Mo(NAr)(ORF3)2 (2) (Ar = 2,6- Pr 2 i C6H3; RF3 = CMe2CF3) have been prepared by the reactions of vinyl silicon reagents Me2Si(CH CH2)2 and PhSi(CH CH2)3 with known alkylidene compound PhMe2C–CH Mo(NAr)(ORF3)2. Complexes 1 and 2 were structurally characterized. Ring opening metathesis polymerization (ROMP) of cyclooctene using compounds 1 and 2 as initiators led to the formation of high molecular weight polyoctenamers with predominant trans-units content in the case of 1 and predominant cis-units content in the case of 2.

Bimetallic alkylidene complexes of tungsten (R′O)2(ArN)W CH–SiR2–CH W(NAr)(OR′)2 (R = Me (1), Ph (2)) and (R′O)2(ArN)W CH–SiMe2SiMe2–CH W(NAr)(OR′)2 (3) (Ar = 2 , 6 – Pr 2 i C 6 H 3 ; R′ = CMe2CF3) have been prepared by the reactions of divinyl silicon reagents R2Si(CH CH2)2 with known alkylidene compounds R′′–CH Mo(NAr)(OR′)2. (R′′ = But, PhMe2C) Complexes 1–3 were structurally characterized. Ring opening metathesis polymerization (ROMP) of cyclooctene using compounds 1–3 as initiators led to the formation of high molecular weight polyoctenamers with predominant trans-units content in the case of 1 and 3 and predominant cis-units content in the case of 2.

Novel silicon- and germanium-containing tungsten complexes Ph3ECH=W(OBu-t)2(OPh)2 were synthesized by the reaction of carbyne derivatives Ph3EC≡W(OBu-t)3 (E = Si, Ge) with phenol and isolated in high yields. Their structure was determined by X-ray diffraction. Individual complexes do not exhibit catalytic activity, whereas in the presence of AlBr3 they initiate metathesis polymerization of cyclooctene.

Catalytic properties of the silicon-containing carbene complexes of tungsten Me3Si-CH=W(NAr)(OR′)2(1) and PhMe2Si-CH=W(NAr)(OR′)2 (2) and their hydrocarbon analogs Me3C-CH=W(NAr)(OR′)2 (3) and PhMe2C-CH=W(NAr)(OR′)2 (4) (Ar = 2,6-Pri 2C6H3, R′ = CMe2CF3) were studied in homometathesis of hex-1-ene, metathesis polycondensation of deca-1,9-diene, and ring opening metathesis polymerization of cyclooctene. The nature of the carbene fragment in the tungsten catalysts substantially affects their catalytic activity. Silicon-containing catalysts 1 and 2 were found to be 3−5 times less active than their hydrocarbon analogs 3 and 4. Metathesis polymerization of cyclooctene in the bulk with initiators 1–4 completed within a few minutes to form a block. Stereoregularity of the formed polyoctenamers depends to a considerable extent on the nature of the carbene fragments in the starting initiators. Initiators 1–2 lead to polyoctenamers mainly containing the cis-units, whereas the use of complexes 3 and 4 affords polyoctenamers mainly containing the trans-units. The structures of novel compound 2 and known complexes 1, 3, and 4 were determined by X-ray diffraction analysis.

The molybdenum silicon-containing carbene complexes PhMe2Si—CH=Mo(NAr)(OR)2 (1), Ph2Si[CH=Mo(NAr)(OR)2]2 (2), and (RO)2(ArN)Mo=CH—(SiMe2)2—CH=Mo(NAr)(OR)2 (Ar = 2,6-Pri2C6H3; R = CMe2CF3) were synthesized by the reaction of the R′— CH=Mo(NAr)(OR)2 compounds (R′ = But or PhMe2C) with silicon-containing vinyl reagents. The structures of complexes 1 and 2 and the known PhMe2C—CH=Mo(NAr)(OCMe2CF3)2 compound were established by X-ray diffraction. The catalytic properties of the silicon-containing carbene complexes in homometathesis of hex-1-ene and metathesis polymerization of cyclooctene were studied. The catalytic activity of these complexes and the stereoregularity of the resulting polyoctenamers substantially depend on the nature of the substituent at the carbene carbon atom.

The novel silicon-, germanium- and tin-containing imido alkyl complexes of tungsten of the type (ArN)2W(CH2EMe3)2 ( Ar = 2 , 6 - Pr 2 i C 6 H 3 ; E = Si (1), Ge (2), Sn (3)) have been prepared by the reactions of (ArN)2WCl2(dme) (dme = 1,2-dimethoxyethane) with heteroelement-containing alkyllithium or Grignard reagents Me3ECH2Li (E = Si, Ge), Me3ECH2MgCl (E = Ge, Sn). The title compounds were isolated in high yields as crystalline solids and characterized by elemental analysis, IR, 1H, 13C, 29Si and 119Sn NMR spectroscopy and X-ray diffraction studies. The geometry of the W atoms in the compounds can be described as a distorted tetrahedron.

New germanium-containing tungsten carbyne complexes Ph3GeC≡W(CH2R)3 (R = But or SiMe3) were synthesized by the reaction of the alkoxy derivative Ph3GeC≡W(OBut)3 with alkyllithium reagents RCH2Li. The new compounds were isolated in individual form as crystals in 95 and 90% yields, respectively, and were characterized by elemental analysis, 1H and 13C NMR spectroscopy, and X-ray diffraction. X-ray diffraction study showed that the coordination environment of the W and Ge atoms in the Ph3GeC≡ W(CH2But)3 and Ph3GeC≡W(CH2SiMe3)3 complexes can be described as a distorted tetrahedron.

The data on the synthesis and physicochemical and photo- and electroluminescent properties of carbochain linear polymers containing ions of rare-earth metals bound via chemical or coordination bonds to the polymer chain are summarized. The effects of the ligand environment at lanthanide atoms and the structures of the polymers on their luminescence activity are considered. Possible approaches to increase the efficiency of electroluminescence of polymer lanthanide emitters are discussed.

Alkylidene complex of molybdenum Ph3Si–CH Mo(NAr)(OCMe2CF3)2 (1) ( Ar = 2 , 6 - Pr 2 i C 6 H 3 ) has been prepared by the reaction of Ph3SiCH CH2 with known alkylidene compounds Alkyl-CH Mo(NAr)(OCMe2CF3)2 (Alkyl = But, PhMe2C). According to X-ray diffraction studies the geometry of the Mo atom in (1) can be described as a distorted tetrahedron. Reactions of heteroelement-containing imido alkyl compounds of molybdenum and tungsten (ArN)2M(CH2EMe3)2 ( Ar = 2 , 6 - Pr 2 i C 6 H 3 ; M = Mo. W; E = Si, Ge, Sn) with triflic acid were shown to yield a complex mixture of products among which carbene complexes have not been observed. The formation of carbene complexes of tungsten in low yields was observed by 1H NMR spectroscopy in the reactions of (ArN)2W(CH2EMe3)2 (E = Si, Ge, Sn) with hydrogen chloride in THF-d8. Catalytic properties of heteroelement-containing alkylidene complexes of molybdenum R3E–CH Mo(NAr)(OCMe2CF3)2 (E = Si, Ge; R = Me, Ph) and also hydrocarbon analogs Alkyl-CH Mo(NAr)(OCMe2CF3)2 (Alkyl = But, PhMe2C) in metathesis of 1-hexene were investigated. The catalytic activity of alkylidene complexes was shown to depend essentially on the nature of substituent bonded to carbene carbon atom.

New trinuclear organosilicon, organogermanium, and organotin-containing tungsten carbene complexes Ph2E[CH=WCl2(OBut)2]2 (E = Si, Ge, or Sn) were synthesized by the reaction of the trinuclear carbyne complexes Ph2E[C≡W(OBut)3]2 with HCl. The tin-containing carbene complex is thermally unstable and was identified in solution by 1H and 13C NMR spectroscopy. The silicon-and germanium-tungsten carbene complexes were isolated in high yields as individual crystals and were characterized by elemental analysis, IR spectroscopy, and 1H and 13C NMR spectroscopy. The structure of the silicon-containing complex Ph2Si[CH=WCl2(OBut)2]2 was established by X-ray diffraction.

The novel germanium-containing alkylidene complexes of molybdenum R3Ge–CH Mo(NAr)(OCMe2CF3)2 (Ar = 2,6-i-Pr2C6H3; R = Me, Ph) have been prepared by the reaction of organogermanium vinyl reagents R3 GeCH CH2 with known alkylidene compounds Alkyl–CH Mo(NAr)(OCMe2CF3)2 (Alkyl = But, PhMe2C). The titled compounds were isolated as crystalline solids and characterized by elemental analysis, 1H NMR, 13C NMR spectroscopy and X-ray diffraction studies. The geometry of the Mo atoms in the compounds can be described as a distorted tetrahedron.