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A new yttrium(iii) complex with the pincer type bis(phosphinophenyl)amide ligand was synthesized and its activity and selectivity in the isoprene polymerization reaction was studied. An ultrahigh molecular weight polyisoprene with a > 99% content of 1,4-cis units was obtained.

A new approach to the synthesis of 3-nitroindoles using palladium-catalyzed arylation of nitromethane with N-(2-bromoaryl)imidates was developed. A convenient and rapid method for cyclization of ethyl N-(2-nitromethylaryl)acetimidates to 2-methyl-3-nitro-1H-indoles was proposed.

Borylation of arenes with bis(pinacolato)diboron catalyzed by sterically encumbered NHC platinum complexes proceeds predominantly at ortho-position even in the absence of a directing group (o : m : p ratio up to 10: 3: 1). The similar borylation with pinacolborane would proceed less selectively.

We have investigated the role of ring sizes and substituents in NHC ligands in some (NHC)Au(I) complexes in the hydration of internal alkynes. Despite the fact that using (NHC)Au(I) complexes in the hydration of diarylacetylenes leads to Markovnikov-type products, the precise tuning of ligands allows changing the regioselectivity in arylalkylacetylene hydration to the anti-Markovnikov-type.

A series of heteroleptic cyclometallated 1,2,3-triazol-5-ylidene IrIII complexes were synthesized and structurally characterized. These new complexes demonstrated photoluminescence in green (550 nm) and cyan (499, 496 nm) regions. Their photophysical properties were rationalized using DFT calculations.

A series of novel (NHC)PdCl2-PR3 complexes were synthesized and fully characterized by 1H, 13C, 31P NMR and FT-IR spectroscopy. These complexes showed high catalytic activity toward solvent-free Buchwald-Hartwig amination. Both primary and secondary amines were efficiently utilized under the same reaction conditions. The solvent-free synthesis of valuable N-aryl carbazoles and similar N-heterocyclic systems was described.

trans-1-Alkoxy-2-(phenylethynyl)cyclopropanes undergo lithiation at the hydrogen atom in the α-position to the triple bond on treatment with BuLi in THF at–(65—70) °C. The resulting organolithium derivatives react with acetaldehyde, acetone, dimethyl disulfide, and methyl chloroformate giving the corresponding alcohols, sulfides, and esters with the yields up to 69% with complete retention of cyclopropane ring stereoconfiguration. The obtained methyl 3-alkoxy-2,2-dimethyl-1-(phenylethynyl)cyclopropanecarboxylates and the corre-sponding acid readily undergo ring opening with addition of water molecule or HCl.

Novel heteroleptic cyclometallated 1,2,3-triazol-5-ylidene IrIII complexes with 2-(5-trifluoromethyl-2H-1,2,4-triazol-3-yl)pyridine or 2-(1H-tetrazol-5-yl)pyridine as the ancillary ligands demonstrate photoluminescence in green (520 nm) and blue (450–480 nm) regions.

An environmentally friendly and efficient synthesis of fully substituted 1,2,3-triazoles comprises solvent-free palladium-catalyzed Suzuki cross-coupling of halo-1,2,3-triazoles with pinacol arylboronates. The efficiencies of Stille and Suzuki reactions with halotriazoles under solvent-free conditions were compared.

Although benzotriazoles are important and ubiquitous, currently there is only one conceptual approach to their synthesis: bridging the two ortho-amino groups with an electrophilic nitrogen atom. Herein, we disclose a new practical alternative – the endo-cyclization of 2-azidoaryl lithiums obtained in situ from 2-azido-aryl bromides. The scope of the reaction is illustrated using twenty-four examples with a variety of alkyl, alkoxy, perfluoroalkyl, and halogen substituents. We found that the directing effect of the azide group allows selective metal–halogen exchange in aryl azides containing several bromine atoms. Furthermore, (2-bromophenyl)diazomethane undergoes similar cyclization to give an indazole. Thus, cyclizations of aryl lithiums containing an ortho–X = Y = Z group emerge as a new general approach for the synthesis of aromatic heterocycles. DFT computations suggested that the observed endo-selectivity applies to the anionic cyclizations of other functionalities that undergo “1,1-additions” (i.e., azides, diazo compounds, and isonitriles). In contrast, cyclizations with the heteroatomic functionalities that follow the “1,2-addition” pattern (cyanates, thiocyanates, isocyanates, isothiocyanates, and nitriles) prefer the exo-cyclization path. Hence, such reactions expand the current understanding of stereoelectronic factors in anionic cyclizations.

It was found that the recrystallization of the adduct Mn[(OOCC5H4)Mn(CO)3]2[O(H)Me]4 from hot acetonitrile in the presence of benzene produces polymer [μ-(OOCC5H4)Mn(CO)3]4[μ-η2-(OOCC5H4)Mn(CO)3]2(NCMe)2(OH2)2([μ-η2-(OOCC5H4)Mn(CO)3]2)[μ-(OOCC5H4)Mn(CO)3]4[μ-η2-(OOCC5H4)Mn(CO)3]2(OH2)2n. The obtained polymer was characterized by X-ray diffraction analysis.

The synthesis and structural characterization of a series of novel platinum(0) complexes were reported. A number of (NHC)Pt(dvtms) (dvtms = 1,3-divinyl-1,1,3,3-tetramethyldisiloxane) complexes were investigated in catalytic addition of B2Pin2 to terminal alkenes. The novel expanded ring N-heterocyclic carbene complex (7-Dipp)Pt(dvtms) showed highest performance, turnover numbers up to 3800 were achieved. The scope of the reaction was illustrated by 20 examples with a variety of alkyl, alkoxy, halogen, ester, ketone and acetal substituents.

A general, economical, and environmentally friendly method of amide synthesis from phenyl esters and aryl amines was developed. This new method has significant advantages compared to previously reported palladium-catalyzed approaches. The reaction is performed transition metal- and solvent-free, using a cheap and environmentally benign base, NaH. This approach enabled us to obtain target amides in high yields with high atom economy.

The reaction between aqueous zinc acetate and cimantrene carboxylic acid has been found to yield Zn[(OOCC5H4)Mn(CO)3] 2[O(H)Me]4, whose dissolution in tetrahydrofuran (THF) gives trinuclear Zn3[μ-(OOCC5H4)Mn(CO)3]4[μ-η2-(OOCC5H4)Mn(CO)3]2(THF)4. Labile THF molecules can be replaced by bidentate 1,10-phenanthroline under mild conditions, thus resulting in Phen2Zn3[μ-(OOCC5H4)Mn(CO)3]4[μ-η2- (OOCC5H4)Mn(CO)3]2. Variations in the reagent ratio and the reaction conditions result in mononuclear PhenZn[(OOCC5H4)Mn(CO)3]2(H2O), which contains a coordinated water molecule. The synthesized complexes have been separated with high yields in the form of single crystals and characterized by chemical analysis, IR spectroscopy, and X-ray diffraction.

We have found that the reaction of aqueous cobalt acetate with cymantrenecarboxylic acid in methanol results in the formation of adduct Co[(OOCC5H4)Mn(CO)3]2[O(H)Me]4, which recrystallizes from acetonitrile or THF to yield trinuclear complexes Co3[μ-(OOCC5H4)Mn(CO)3]4[μ-η2-(OOCC5H4)Mn(CO)3]2L4, where L = NCMe or THF, respectively, with a linear metal core. These complexes have been characterized by chemical analysis, IR spectroscopy, and X-ray diffraction analysis.

Adducts Ni[(OOCC5H4)Mn(CO)3]2[O(H)Me]4 and Cu2(µOOCMe)2[µ(OOCC5H4)Mn(CO)3]2[O(H)Me]2 were prepared by reacting aqueous copper(II) and nickel(II) acetates in boiling MeOH. These complexes, as well as the products of their crystallization from MeCN were characterized by chemical analysis, IR spectroscopy, and X-ray diffraction.

Reactions of manganese(II) pivalate, benzoate, and cymantrenecarboxylate with 3,5-dimethylpirazole (Hdmpz) have been found to result in mononuclear complexes (Hdmpz)4Mn(OOCR) where R = But and Ph, respectively, and binuclear complex {Mn(μ-OOCC5H4Mn(CO)3)(OOCC5H4Mn(CO)3) (Hdmpz)2(OH2)}2 which contains a pyrazole solvate molecule. The obtained complexes have been isolated in high yields as single crystals and have been characterized by chemical analysis, IR spectroscopy, and X-ray diffraction.

The reaction between aqueous zinc acetate and two moles of cymantrene carboxylic acid under mild conditions is found to give rise to {(H2O)Zn(μ,η2-OOCMe)[η5-C5H4(COO)]Mn(CO)3 polymer, whose reaction with 3,5-dimethylpyrazole yields binuclear pyrazolate-bridged complex Zn2(μ-dmpz)2(Hdmpz)2[η5-C5H4(COO)]Mn(CO)3]2. The structure of the resulting complexes was identified by X-ray diffraction.