Нифантьев Илья Эдуардович
Базовая кафедра нефтехимии и полимеров Института нефтехимического синтеза им А.В. Топчиева РАН
Профессиональные интересы
Должности
- Профессор — Базовая кафедра нефтехимии и полимеров Института нефтехимического синтеза им А.В. Топчиева РАН
Био
- · Начал работать в НИУ ВШЭ в 2013 году.
Образование
- 1993 · Доктор наук
- 1985 · Специалитет: Московский государственный университет им. М.В. Ломоносова, специальность «Химия», квалификация «Химик»
Опыт работы
- · 2004: с года по н.в. занимает должность профессора по кафедре органической химии в МГУ имени М.В.Ломоносова, химический факультет
- · 2010: В году (по н.в.) поступил по совместительству на работу в ИНХС РАН на позицию заведующего Лабораторией металлоорганического катализа (№8)
Награды и поощрения
- · Надбавка за публикацию в журнале из Списка А (и приравненном к нему научном издании) (2025–2026, 2024–2025, 2023–2024)
- · Надбавка за публикацию в международном рецензируемом научном издании (2022–2023, 2021–2022)
- · Лучший преподаватель — 2023
Гранты и проекты
- — · на соискание учёной степени кандидата наук
Идентификаторы исследователя
- ORCID:
0000-0001-9151-1890 - ResearcherID:
O-1872-2013 - Google Scholar: https://scholar.google.com/citations?user=Crz3AmUAAAAJ&hl=en
- Scopus AuthorID:
6701810372
Публикации (41)
Mechanistic Insights of Ethylene Polymerization on Phillips Chromium Catalysts
2024 · ARTICLE · en
Silica-supported chromium oxide catalysts, also named Phillips chromium catalysts (PCCs), provide more than half of the world’s production of high- and medium-density polyethylenes. PCCs are usually prepared in the Cr(VI)/SiO2 form, which is subjected to reductive activation. It has been explicitly proven that CO reduces Cr(VI) to Cr(II) species that initiate ethylene polymerization; ethylene activates Cr(VI) sites as well, but the nature of the catalytic species is complicated by the presence of the ethylene oxidation products. It is widely accepted that the catalytic species are of a Cr(III)–alkyl nature, but this common assumption faces the challenge of “extra” hydrogen: the formation of similar species under the action of even-electron reducing agents requires an additional H atom. Relatively recently, it was found that saturated hydrocarbons can also activate CrOx/SiO2, and alkyl fragments turn out to be bonded with a polyethylene chain. In recent years, there have been numerous experimental and theoretical studies of the structure and chemistry of PCCs at the different stages of preparation and activation. The use of modern spectral methods (such as extended X-ray absorption fine structure (EXAFS), X-ray absorption near-edge structure (XANES), and others); operando IR, UV–vis, EPR, and XAS spectroscopies; and theoretical approaches (DFT modeling, machine learning) clarified many essential aspects of the mechanisms of CrOx/SiO2 activation and catalytic behavior. Overall, the Cosse–Arlman mechanism of polymerization on Cr(III)–alkyl centers is confirmed in many works, but its theoretical support required the development of nontrivial and contentious mechanistic concepts of Cr(VI)/SiO2 or Cr(II)/SiO2 activation. On the other hand, conflicting experimental data continue to be obtained, and certain mechanistic concepts are being developed with the use of outdated models. Strictly speaking, the main question of what type of catalytic species, Cr(II), Cr(III), or Cr(IV), comes into polymerization still has not received an unambiguous answer. The role of the chemical nature of the support—through the prism of the nature, geometry, and distribution of the active sites—is also not clear in depth. In the present review, we endeavored to summarize and discuss the recent studies in the field of the preparation, activation, and action of PCCs, with a focus on existing contradictions in the interpretation of the experimental and theoretical results.
Heterocene Catalysts for Copolymerization of Hex-1-ene and Polar Vinyl Monomers
2024 · ARTICLE · en
The paper proposes a series of promising Zr(IV) complexes and experimentally confirms that, when activated with minimal amounts of modified metylaluminoxane MMAO-12 ([Al]/[Zr] ~20–40), these complexes are able to initiate copolymerization of hex-1-ene with polar vinyl monomers FG-(CH2)8CH=CH2 [where FG is a functional group selected from C(O)NMe2, CH2OSiMe3, C(O)OiPr, and CH2OH]. The prepared copolymers were characterized by 1H and 13C NMR spectroscopy, size exclusion chromatography, and differential scanning calorimetry. Isotactic copolymers of hex-1-ene with 10-undecen-1-ol with polar comonomer content up to 32.2 mol % have been synthesized for the first time. An investigation of the adhesive properties of the prepared copolymers has shown that incorporating 10-undecen-1-ol enhances the adhesive fracture energy by a factor of 32 compared to the respective homopolymer.
Rational design of ansa-heterocenes with a long SiOSi bridge as a catalysts for selective dimerization of oct-1-ene
2024 в печати · ARTICLE · en
Being activated by methylalumoxane ([Al]/[Zr] = 10), (η5-C5H5)2ZrCl2 (Zr1) and [(η5-C5H4SiMe2)2O]ZrCl2 (Zr2) catalyze selective dimerization of α-olefins with low productivity (turnover number TON ∼2000). Our previous research of heterocycle-fused ansa-zirconocenes revealed that SiMe2-bridged complexes catalyze polymerization of α-olefins, whereas CH2CH2-bridged complexes are high-performance oligomerization catalysts (TON ∼ 4∙105). We proposed that further elongation of the bridge will allow obtaining dimerization catalysts. New –SiMe2OSiMe2– bridged ansa-zirconocenes Zr3–Zr11 were synthesized and studied in oct-1-ene dimerization at 100 °C and [oct-1-ene]/[Zr] ratio of 3∙104. In the absence of H2 bis(5,6-dihydroindeno[2,1-b]indole) derivatives Zr8 and Zr9 demonstrated high activity and dimerization selectivity up to 94%. In the presence of H2 symmetrical indenoindole complexes Zr5–Zr9 appeared to be even more active, but up to 24% of hydrogenated oct-1-ene dimer HC16 was formed. Mixed-ligand complexes Zr10 and Zr11 catalyzed oct-1-ene dimerization with up to 99% selectivity without the formation of HC16 even in trace amounts.
Synthesis, melt molding and hydrolytic degradation of poly(L-lactide-co-l-methylglycolide) and its composites with carbonated apatite
2024 · ARTICLE · en
Poly(lactic-co-glycolic acid)s (PLGAs) hold considerable significance for their biomedical applications. Biodegradation and mechanical properties of PLGAs and PLGA-based composites are strongly influenced by lactate/ glycolate (L/G) ratio in copolymers, molecular weight characteristics and microstructure of PLGAs. The common approach to PLGAs is based on ring-opening copolymerization of lactides and glycolide, the products of which contain long (L)n and (G)n segments. An efficient but expensive approach to PLGAs with given L-G sequences is a segmer assembly polymerization that is hardly applicable for the synthesis of high-MW PLGAs. In the present work, for the first time we synthesized lactate-enriched PLGAs using ring-opening copolymerization of L-lactide (L-LA) with L-methylglycolide (L-MeGL) in 85:15 and 70:30 molar ratios, resulting in L-PLMG 85/15 and L-PLMG 70/30 copolymers. L-PLGA 85/15 with the same L/G ratio as in PLMG 70/30 was synthesized by ring-opening copolymerization of L-LA with glycolide as a sample for a comparison. According to 1H and 13C NMR data and [α]D measurements, L-MeGL-based PLGAs had a unique microstructure, e.g. macromolecules of L-PLMG 85/ 15 consisted of Ln sequences with single G insertions. Composites of PLLA and three samples of PLGAs with plate- like carbonated apatite (pCAp) containing 25 and 50 wt.% of the filler were prepared. Rectangular specimens from (co)polymers and (co)polymer composites were obtained by injection molding and studied. Due to the absence of highly reactive (G)n fragments, L-PLMG 85/15 and PLMG 70/30-based materials demonstrated higher thermal and hydrolytic stability, mechanical testing showed that L-MeGL-based copolymers provide better maintaining of the bending strength in comparison with L-PLGA 85/15 matrix.
The interplay between structural features and the efficiency of the energy transfer process in terbium complexes with triarylcyclopentadienyl ligands
2024 · ARTICLE · en
erbium and gadolinium complexes with triarylcyclopentadienyl ligands having electron-donating methoxy substituents in the ortho- (CpPh2Ar−o) and para- (CpPh2Ar−p) positions of one of the phenyl rings have been synthesized. Different structural types, including tetranuclear [{CpPh2Ar−oTb (THF)}2 (μ2-Cl)2(μ3-Cl)3K (THF)]2 (Tb1), [{CpPh2Ar−oTb}2 (μ2-Cl)2 (μ3-Cl)3K]2 (Tb3), [{(CpPh2Ar−oTb)2 (μ2-Cl)3}2 (μ2-Cl)2] (Tb5), [{CpPh2Ar−pTb (THF)}2 (μ2-Cl)2 (μ3-Cl)3K (THF)]2 (Tb6), binuclear [{CpPh2Ar−oTb (THF)Cl}2 (μ2-Cl)2] (Tb4), [{CpPh2Ar−pTb (THF)}2 (μ2-Cl)2 (μ3-Cl)3K (THF)]2 (Tb7), [CpPh2Ar−p2Tb (μ2-Cl) (μ3-Cl)K]2 (Tb8) and mononuclear [CpPh2Ar−o2TbCl] (Tb2) complexes have been obtained and confirmed by single crystal X-ray diffraction analysis. All designed terbium complexes exhibit high quantum yields of the photoluminescence (up to 65 %). The introduction of a methoxy group into one of the phenyl rings of the triarylcyclopentadienyl ligand leads to a more than twofold increase in the quantum yield of the terbium ion luminescence. The estimated values of radiative rate krad of the terbium ion vary in the range of 0.23–0.69 ms. The presence of the methoxy group as well as the mutual disposition of the phenyl rings promotes the appearance of an intraligand charge transfer states involved in the energy transfer process. Due to a lowering of the energy of the interconfigurational 4f −5d transitions caused by the relatively strong crystal field of the Cp ligand in bis(cyclopentadienyl) terbium complexes, the quantum yield of the photoluminescence is high at the short lifetimes of the 5D4 level of the terbium ion.
Phenyl substitution as an effective way to control the luminescent properties of polyphenylcyclopentadienyl lanthanide complexes
2024 · ARTICLE · en
Lanthanide complexes [CpXLnCl2(Me3tach)]n (Ln = Tb, Gd; CpX = Cp, CpPh, CpPh; Me3tach = 1,3,5-trimethyl-1,3,5- triazacyclohexane; n = 1, 2), containing cyclopentadienyl (Cp), 1,3-diphenylcyclopentadienyl (CpPh) and tetraphenyl- cyclopentadienyl (CpPh) anions as ν-bonded antenna ligands, have been synthesized. A combined analysis of quantum chemical, optical and X-ray diffraction data has shown that the introduction of phenyl groups into the Cp ring leads to the inevitable appearance of intraligand charge transfer states due to the nonequivalence of the phenyl rings.
Tridentate Nitrogen Ligand as a Tool for the Construction of Well-Defined Rare Earth Trichloride Complexes
2024 · ARTICLE · en
nCl3(THF)3 (Ln = Y, La ÷ Nd, Sm ÷ Lu) readily react with the tridentate 1,3,5-trimethyl-1,3,5-triazacyclohexane (Me3tach) ligand to form mono- or binuclear lanthanide trichloride complexes, depending on the stoichiometry of the reaction and the ionic radius of the metal: mononuclear pseudosandwich [LnCl3(Me3tach)2], (Ln = Y, La ÷ Ho) or binuclear complexes [Ln2Cl6(Me3tach)3], or [LnCl3(Me3tach)(THF)]2 (Ln = Sm, Tb). Detailed analysis of the NMR data of [LnCl3(Me3tach)2] complexes with paramagnetic lanthanide ions showed that their structures remained unchanged in the toluene solution. A series of isomorphous complexes [LnCl3(Me3tach)(Py)2] (Ln = La, Sm, Tb, Er, Lu; Py = pyridine) have been obtained by the recrystallization of either mononuclear or binuclear complexes from pyridine. Complexes of terbium and europium ions with the Me3tach ligand exhibit relatively high quantum yields of metal-centered luminescence (0.39 and 0.32, respectively).
Crystalline Micro-Sized Carbonated Apatites: Chemical Anisotropy of the Crystallite Surfaces, Biocompatibility, Osteoconductivity, and Osteoinductive Effect Enhanced by Poly(ethylene phosphoric acid)
2023 · ARTICLE · en
Carbonated hydroxyapatites (CAp) are very close to natural bone apatite in chemical composition and are regarded as a prospective bone mineral substitute for bone surgery and orthopedics. However, until now, the studies and applications of CAp were limited because of the amorphous nature of the synthetic CAp. In the present work, microsized highly crystalline carbonated apatites with uniform hexagonal (hCAp) or platelike (pCAp) morphology have been studied for the first time in vitro and in vivo, comparing against commercial hydroxyapatite (HAp) and β-tricalcuim phosphate (βTCP). In vitro experiments on dissolution of those calcium phosphate ceramics (CPCs) in acetate (pH 5.5) and Tris (pH 7.3) buffer solutions showed the following rank order of the dissolution rates: βTCP > hCAp > pCAp > HAp. The higher dissolution rate of hCAp in comparison with pCAp is explained by chemical anisotropy of the crystallite surfaces, which was proven by SEM studies of the changes in the morphology of hCAp and pCAp crystallites during hydrolysis. A 5-week experiment on subcutaneous implantation of CPC species showed the following rank order of bioresorption rates: βTCP > pCAp > hCAp > HAp. pCAp matrixes exhibited the highest biocompatibility, confirmed by histomorphological analysis. Three-month bone regeneration experiments involving a rat tibial defect model were conducted with 250−500 μm granules of pCAp and pCAp-PEPA [pCAp, pretreated with 2 wt % poly(ethylene phosphoric acid)]. Notably, pCAp-PEPA implants were resorbed at higher rates and induced the formation of more mature osseous tissue, a compact bone with Haversian systems.
(Cyclopentadienyl)neodymium borohydrides with auxiliary N3-heterocyclic ligands
2023 · ARTICLE · en
Mononuclear [CpNd(BH4)2L] borohydrides comprising L = 1,3,5-trimethyl-1,3,5-triazacyclohexane (Me3tach) and L = 1,4,7-trimethyl-1,4,7-triazacyclononane (Me3tacn) were obtained and structurally characterized. Their catalytic activity in coordination–insertion ring-opening polymerization of e-caprolactone was studied.
1,2,4-ТРИФЕНИЛЦИКЛОПЕНТАДИЕНИЛЬНЫЕ КОМПЛЕКСЫ ПРАЗЕОДИМА И ЭРБИЯ
2023 · ARTICLE · ru
Взаимодействие трифенилциклопентадиенилкалия с тетрагидрофуранатами хлоридов празеодима и эрбия, в зависимости от соотношения реагентов, приводит к образованию тетраядерных ат-ком- плексов [{(Ph3C5H2)Pr(THF)}2(μ2-Cl)2(μ3-Cl)3K]2(C7H8)4 (I) и [{(Ph3C5H2)Er(THF)}2(μ2-Cl)2(μ3- Cl)3K(THF)]2 (III); и биядерных ат-комплексов [(Ph3C5H2)2LnCl(KCl)]2 Ln = Pr (II), Er (IV) (CCDC № 2224244 (I), 2224243 (II), 2224245 (III), 2224242 (IV)). В основе сходных по строению комплексов I и III лежит остов {[Ln2(μ-Cl)3]2(μ-Cl)2K2}, в III катион калия дополнительно координирован моле- кулой ТГФ. В основе строения изоструктурных II и IV биядерный остов [Ln(μ-Cl)2K]2.
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