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This paper describes our recent results in the field of zirconocene-catalyzed α-oltfin transformations, and focuses on questions regarding the reaction mechanism, rational design of zirconocene pre-catalysts, as well as prospective uses of α-olefin products. It has been determined that a wide range of α-olefin-based products, namely vinylidene dimers, oligomers and polymers, can be prepared via catalysis by zirconocene dichlorides, activated by a minimal (10–20 eq.) amount of MAO. We assumed that in the presence of minimal quantities of MAO, various types of zirconocene catalysts form different types of catalytic particles. In the case of bis-cyclopentadienyl complexes, the reactive center is formed under the influence of R2AlCl, which makes the chain termination via β-hydride elimination significantly easier, with α-olefin dimers being formed as the primary product. Bis-indenyl complexes and their heteroanalogues, form stable cationic catalytic particles and effectively catalyze the polymerization. Mono-indenyl and mono-substituted bis-cyclopentadienyl-ansa complexes catalyze α-olefin oligomerization. Effective catalysts of dimerization, oligomerization and polymerization of α-olefins in the presence of minimal MAO quantities are proposed. Prospects of using α-olefin dimers, oligomers and polymers in the synthesis of branched hydrocarbon functional derivatives (dimers), high quality, low viscosity motor oils (oligomers), and thickeners and absorbents (polymers) are examined.

A new approach to design "antenna-ligands" to enhance the photoluminescence of lanthanide coordination compounds has been developed based on a π-type ligand-the polyphenyl-substituted cyclopentadienyl. The complexes of di-, tri-, and tetraphenyl cyclopentadienyl ligands with Tb and Gd have been synthesized and all the possible structural types from mononuclear to di- and tetranuclear complexes, as well as a coordination polymer were obtained. All types of the complexes have been studied by single-crystal X-ray diffraction and optical spectroscopy. All terbium complexes are luminescent at ambient temperature and two of them have relatively high quantum yields (50 and 60%). Analysis of energy transfer process has been performed and supported by quantum chemical calculations. The role of a low-lying intraligand charge transfer state formed by extra coordination with K in the Tb ion luminescence sensitization is discussed. New aspects for design of lanthanide complexes containing π-type ligands with desired luminescence properties have been proposed.

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A new family of lanthanide complexes with di- and triphenylacetate ligands was prepared from LnCl3. Dimeric diphenylacetates were the only isolated products of the reaction between LnCl3 (Ln = La, Nd) and Ph2CHCOONa. The exchange reaction between LnCl3 and Ph3CCOONa led to the formation of three structurally different types of neodymium and lanthanum complexes under different reaction conditions. Various coordination modes of the carboxylate ligands were revealed, including κ2- and κ1-terminal coordination, μ2-κ1:κ1-bridging, and μ2-κ1:κ2-semibridging. The treatment of La and Nd tris-triphenylacetates with excess AlEt3 produces the dimeric tetraethylaluminates [Ln2((μ2-κ1:κ1-Ph3CCOO)4(AlEt4)2]. The structures of the key La and Nd triphenylacetates that were obtained from these reactions were verified by X-ray diffraction, and the complex [(THF)4Nd2(Ph2CHCOO)2(μ2-κ1:κ2-Ph2CHCOO)2(μ2- κ1:κ1-Ph2CHCOO)2] was studied by high-resolution X-ray diffraction. Neodymium di- and triphenylacetate complexes can serve as precursors of catalysts for butadiene and isoprene stereospecific 1,4-cis polymerization.

Zirconocene-mediated selective dimerization of α-olefins usually occurs when precatalyst (η5-C5H5)2ZrCl2 is activated by minimal excess of methylalumoxane (MAO). In this paper, we present the results of density functional theory (DFT) simulation of the initiation, propagation, and termination stages of dimerization and oligomerization of propylene within the framework of Zr-Al binuclear mechanism at M-06x/DGDZVP level of theory. The results of the analysis of the reaction profiles allow to explain experimental facts such as oligomerization of α-olefins at high MAO/(η5-C5H5)2ZrCl2 ratios and increase of the selectivity of dimerization in the presence of R2AlCl. The results of DFT simulations confirm the crucial role of the presence of chloride in the selectivity of dimerization. The molecular hydrogen was found in silico and proven experimentally as an effective agent that increases the rate and selectivity of dimerization.

We elaborated a synthetic approach to a new family of PNP ligands that involves assembling sequential molecules based on the rigid 5,6-dihydrodibenzo­[c,e]­[1,2]­azaphosphinine backbone (−Z−). This approach allowed us to obtain PNP-type ligands of the general formula Ar2P–Z–Ar′ (Ar, Ar′ = Ph, o-MeOC6H4) with high yields and without the formation of PPN byproducts. Ar2P–Z–Ar′/Cr­(acac)3 (acac = acetylacetonate) adducts activated by modified methylalumoxane (MMAO-12) effectively catalyzed ethylene oligomerization; the number of ortho-methoxyphenyl fragments n controls the direction of the process, from slow polymerization (n = 0) to rapid oligomerization (n = 3), thereby producing a mixture of 1-hexene and 1-octene in ∼2:1 ratio with very low formation of polyethylene (∼0.6%).