Нифантьев Илья Эдуардович

Tris(triphenylcyclopentadienyl) lanthanide complexes – at the edge of steric overcrowding

2026 · ARTICLE · en

A series of tris(triphenylcyclopentadienyl) ate-complexes [Cp3Ph3LnCl]􀀀 [MLn]+ (Ln = La, Ce, Pr) MLn = Li(THF)4 (Ln1), K(18-crown-6)(THF) (Ln2), Na(THF)6 (La3) were synthesized by the straightforward salt-metathesis method. All the structural types have been studied by single-crystal X-ray diffraction. The formation of complexes results from the concerted arrangement of the phenyl substituents of the three bulky triphenylcyclopentadienyl ligands respect to each other. Synthesis of tris(triphenylcyclopentadienyl) complexes of lanthanides with an ionic radius less than that of praseodymium could not be achieved. In conditions unfavorable for formation of the ate-complex, only La3, can be obtained, cerium reaction results in an inseparable mixture of compounds, while praseodymium yields the bis(cyclopentadienyl) complex [Cp2Ph3PrCl(THF)] (Pr4).

Methylenealkane-based dialkylammonium alkenyl succinamide and poly(alkenylene-alt-succinamide) wax anti-settling additives for diesel fuels: synthetic availability, performance and versatility

2026 · ARTICLE · en

Europium Coordination Compounds for the Design of a Polyethylene-Based Luminescent Composite Material

2025 · ARTICLE · en

The reaction of europium dibenzoylmethanate complex Na+[Eu(Dbm)4]– with 1-alkyl-4-dimethylaminopyridinium salts gives compounds [RNC5H4NMe2]+[Eu(Dbm)4]– (Dbm = [PhC(O)CHC(O)– Ph]), where R = C10H21 (I) or a set of oligomers CnH2n+1, (n is even) ([(R-NC5H4NMe2)]I) with a weightaverage molecular weight Mw = 1520 (II). The molecular structure of complex I was established by X-ray diffraction analysis (CCDC no. 2405293). Compounds I and II were used as the luminescent components for a luminescent composite material based on low-density polyethylene (LDPE). The optical properties of complexes I and II and LDPE-based composite materials prepared using I and II were investigated

Yttrium Polyphenylcyclopentadienyl Complexes with 1,3,5-Trimethyl-1,3,5-triazacyclohexane

2025 · ARTICLE · en

in the presence of 1,3,5-trimethyl-1,3,5-triazacyclohexane (Me3tach) gives complexes of the type [Cp'Y(Me3tach)Cl2] (Cp' = Ph2C5H3 (CpPh2) (I), Ph3C5H2 (CpPh3) (II), Ph4C5H (CpPh4) (III). The molecular structure of complexes I–III was established by X-ray diffraction (CCDC nos. 2406644 (I), 2406645 (II), 2406646 (III)). The main structural parameters of all of the obtained monocyclopentadienyl complexes were similar, irrespective of the number of phenyl substituents in the cyclopentadienyl ligand. According to NMR spectroscopy data, compounds I and III retained their structure in THF solution

Yttrium Chloride Complexes with 1,3,5-Trimethyl-1,3,5-triazacyclohexane: Unprecedented Structural Diversity

2025 · ARTICLE · en

Specific features of the structures of five various complexes [Y(Me3tach)Cl3(THF)2] (I), [Y(Me3tach)2Cl3] (II), [Y(Me3tach)Cl2(μ-Cl)2YCl2(THF)3] (III), [Y(Me3tach)Cl3(THF)]2 (IV), and [Y(Me3tach)2Cl2]+[Y(Me3tach)Cl4]– (V) formed via the reaction of yttrium chloride tetrahydrofuranate with 1,3,5-trimethyl-1,3,5-triazacyclohexane (Me3tach) are compared. The molecular structures of newly synthesized complexes IV and V are determined by X-ray diffraction (XRD) (CIF files CCDC nos. 2484944 and 2484945, respectively). All complexes, except for complex V, demonstrate similar metal–ligand distances with a correction to the difference in coordination numbers regardless of the structure of the complex and metal to ligand ratio for both mono- and binuclear complexes.

Bis(1,2,4-triphenylcyclopentadienyl) Terbium 4,4,4-trifluoro-1-phenylbutane-1,3-dionate

2025 · ARTICLE · en

A new bis(cyclopentadienyl) terbium(III) complex with 1,2,4-triphenylcyclopentadienyl and 4,4,4-trifluoro-1-phenylbutane-1,3-dionate ligands was synthesized. Single-crystal X-ray analysis revealed a mononuclear bis(cyclopentadienyl) complex with a diketonate ligand in the bisector plane. The compound under study exhibits a ligand ligand charge transfer state (LLCT), according to optical spectroscopy and crystallographic data.

Synergistic Effect of Poly(ethylenephosphoric Acid) and Cerium in Bone Substitute Composites on Tissue Response and Bone Remodeling

2025 · ARTICLE · en

To reduce the time of postoperative recovery and to prevent post-surgical complications, biocompatible synthetic materials with osteoconductive and osteoinductive properties are used as bone substitutes in large bone defect management. A simplified biomimetic approach to similar materials is based on the use of an inorganic filler, a polymer matrix, and a compatibilizer, mimicking the composition of the natural bone. Based on plate-like micro-sized carbonated hydroxyapatite (pCAp), we prepared compression-molded samples optionally containing an additional polyester component (poly(ε-caprolactone) PCL, poly(L-lactide) PLLA, or poly(L-methylglycolide) PLMG); syntheticblock copolymers comprising fragments of the corresponding polyester and poly(ethylene phosphoric acid) (PEPA) were also prepared and studied asa ‘two-in-one’ polymer matrix/compatibilizer. Bone regeneration experiments involving a three-month rat tibial defect model were conducted with 250–500 μm granules of the composites. Comparative studies of the introduction of the polyester-b-PEPA copolymer into composites revealed a positive effect, which manifests itself in accelerated bone regeneration, which further intensified for pCAp/PEPA-b-PLMG. The latter composite formulation was used to study the results of the introduction of cerium into the filler. One-month experiments with pCAp, CePO4-doped pCAp, and composites of these inorganic fillers with PEPA-b-PLMG were conducted. For the first time, a positive synergistic effect of the presence of cerium and PEPA in the composite, which appeared in substitution of the implant material by two-thirds of newly formed partly matured bone, was observed four weeks after surgery.

Coordination copolymerization of α-olefins with non-conjugated polar vinyl monomers: current catalytic approaches and prospects for practical applications

2025 · ARTICLE · en

The reactivity of polar vinyl monomers, unsaturated compounds containing functional groups, depends on the presence or absence of conjugation between the C=C bond and the neighbouring unsaturated moieties or donor heteroatoms. Conjugated polar vinyl monomers (acrylates, vinyl ethers, etc.) (co)polymerize upon free-radical initiation. The reaction is widely used to produce numerous polymer materials that qualitatively differ from polyolefins in their characteristics. Copolymerization of ethylene, propylene, and higher α-olefins with nonconjugated vinyl monomers containing polar or reactive functional groups gives so-called 'functional polyolefins', that is, polymer materials with unique mechanical and rheological characteristics, increased thermal and oxidative stability, and controlled hydrophilicity. In the synthesis of functional polyolefins, only coordination polymerization, catalyzed by complex compounds of Group 4 metals, V, Sc, Ni, and Pd is effective. This review summarizes for the first time data on the (co)polymerization of polar vinyl monomers catalyzed by early transition metal complexes, discusses the current results achieved in the catalysis of copolymerization of polar vinyl monomers by Group 10 metal complexes, and considers the prospects for practical application of functional polyolefins and for organization of their industrial production.The bibliography includes 272 references.

Isotactic copolymerization of but-1-ene with polar vinyl monomers: the effect of ω-alken-1-ol comonomer content on phase behavior, melt rheology, mechanical and adhesive properties of functionalized poly(but-1-ene)s

2025 · ARTICLE · en

Isotactic copolymerization of but-1-ene with bio-based undec-10-en-1-ol (M1), dec-9-en-1-ol (M2) and their silyl esters (M3–M5), catalyzed by C1-symmetric ansa-heterocene [Me2Si(η5-2,4,7-trimethelinden-1-yl)(η5-2,5-dimethyl-7H-cyclopenta[1,2-b:4,3-b']dithiophen-7-yl)]ZrCl2 (Zr1), activated by iBu3Al and MMAO-12, was explored for the first time. At [AlMMAO]/[Zr1] = 40 and [Monomer]/[Zr1] = 5,000, iBu2Al-protected ω-alken-1-ols have demonstrated highest activities and up to 16.7 mol% degrees of the comonomer incorporation with a formation of (co)polymers with moderate stereoregularity (for isotactic poly(but-1-ene) iPB Tm = 93.3 °C). At [AlMMAO]/[Zr1] = 400 and [Monomer]/[Zr1] = 100,000, iPB with Tm = 102.9 °C was formed; the presence of iBu2Al-protected undec-10-en-1-ol (M1-Al) led to substantial increase of the Mn of (co)polymers from 229 kDa (iPB) to 1193 kDa (copolymer containing 3.6 mol% of M1). XRD and DSC studies of the (co)polymers revealed a positive impact of the low comonomer content on the rate of Form II to Form I transition in iPB. Copolymers containing 0.3–0.6 mol% of OH groups showed improved melt rheology and mechanical properties, while the copolymer with 2.0 mol% M1 content turned out to be a hot-melt adhesive for steel with one and a half times higher bonding strength than commercial poly(ethylene-co-vinyl acetate).

Lanthanide Complexes with 1,4,7-Trimethyl-1,4,7-triazacyclononane

2024 · ARTICLE · en

The reaction of 1,4,7-trimethyl-1,4,7-triazacyclononane with samarium, gadolinium, and terbium chloride tetrahydrofuranates gives mononuclear complexes [LnCl3(Me3tacn)(THF)n] (Me3tacn = 1,4,7- trimethyl-1,4,7-triazacyclononane; Ln = Sm (I), Gd (II), n = 1; Ln = Tb (III), n = 0). The treatment of complexes I or II with 1,2,4-triphenylcyclopentadienyl potassium affords mono(cyclopentadienyl) complexes [CpPh3LnCl2(Me3tacn)] (CpPh3 = 1,2,4-triphenylcyclopentadienyl; Ln = Sm (IV), Gd (V)). Complexes IV and V are formed even when a twofold excess of CpPh3K is used. The molecular structure of complexes I–V was established by X-ray diffraction analysis (CCDC nos. 2299485 (I), 2299487 (II), 2299486 (III), 2305352 (IV), 2306051 (V)).