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1.
Nataliya A. Samoylova Nikita M. Belov Victor A. Brotsman Dr. Ilya N. Ioffe Dr. Natalia S. Lukonina Dr. Vitaliy Yu. Markov Dr. Adrian Ruff Alexey V. Rybalchenko Paul Schuler Olesya O. Semivrazhskaya Prof. Dr. Bernd Speiser Prof. Dr. Sergey I. Troyanov Prof. Dr. Tatiana V. Magdesieva Dr. Alexey A. Goryunkov 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(52):17969-17979
Novel difluoromethylenated [70]fullerene derivatives, C70(CF2)n (n=1–3), were obtained by the reaction of C70 with sodium difluorochloroacetate. Two major products, isomeric C70(CF2) mono‐adducts with [6,6]‐open and [6,6]‐closed configurations, were isolated and their homofullerene and methanofullerene structures were reliably determined by a variety of methods that included X‐ray analysis and high‐level spectroscopic techniques. The [6,6]‐open isomer of C70(CF2) constitutes the first homofullerene example of a non‐hetero [70]fullerene derivative in which functionalisation involves the most reactive bond in the polar region of the cage. Voltammetric estimation of the electron affinity of the C70(CF2) isomers showed that it is substantially higher for the [6,6]‐open isomer (the 70‐electron π‐conjugated system is retained) than the [6,6]‐closed form, the latter being similar to the electron affinity of pristine C70. In situ ESR spectroelectrochemical investigation of the C70(CF2) radical anions and DFT calculations of the hyperfine coupling constants provide evidence for the first example of an inter‐conversion between the [6,6]‐closed and [6,6]‐open forms of a cage‐modified fullerene driven by an electrochemical one‐electron transfer. Thus, [6,6]‐closed C70(CF2) constitutes an interesting example of a redox‐switchable fullerene derivative. 相似文献
2.
Transalkylation of Higher Trifluoromethylated Fullerenes with C70: A Pathway to New Addition Patterns of C70(CF3)8 下载免费PDF全文
Nikita M. Belov Marina G. Apenova Alexey V. Rybalchenko Eugenia V. Borkovskaya Dr. Natalia S. Lukonina Dr. Alexey A. Goryunkov Dr. Ilya N. Ioffe Prof. Dr. Sergey I. Troyanov Prof. Dr. Lev N. Sidorov 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(4):1126-1133
We report three new isomers of C70(CF3)8, structurally related to p7mp‐C70(CF3)10, that are inaccessible by direct trifluoromethylation, but can be easily identified among the products of the transalkylation of higher trifluoromethylfullerenes with C70. The reported compounds are characterized by UV/Vis, 1 D and 2 D COSY 19F NMR spectroscopy, and DFT calculations. A rather unusual addition pattern is observed in p6,i‐C70(CF3)8 in which one addend is attached remotely from the others; polarization of the adjacent unsaturated bonds by the addend makes the molecule readily oxidizable. 相似文献
3.
Facile Separation,Spectroscopic Identification,and Electrochemical Properties of Higher Trifluoromethylated Derivatives of [70]Fullerene 下载免费PDF全文
Maria P. Kosaya Alexey V. Rybalchenko Dr. Natalia S. Lukonina Olga N. Mazaleva Dr. Ilya N. Ioffe Dr. Vitaliy Yu. Markov Prof. Dr. Sergey I. Troyanov Prof. Dr. Lev N. Sidorov Dr. Nadezhda B. Tamm Dr. Alexey A. Goryunkov 《化学:亚洲杂志》2018,13(15):1920-1931
We survey the structure and electronic properties of the family of higher trifluoromethylated C70(CF3)n molecules with n=14, 16, 18, and 20. Twenty‐two available compounds, of which thirteen are newly obtained and characterized, demonstrate the broad diversity of π‐system topologies, which enabled us to study the interplay between the CF3 addition pattern and the electronic properties. UV/Vis spectroscopic and cyclic voltammetric studies demonstrate the importance of the exact addition pattern rather than the plain number of addends. Of particular interest is the skew pentagonal pyramid (SPP) addition pattern, which enables formation of closed‐shell cyclopentadienyl anions C70(CF3)n? 1 ? through CF3 detachment upon electron transfer. A detailed study of the process is presented for a SPP‐C70(CF3)16 where potentiostatic electrolysis at the second reduction potential gives C70(CF3)15? oxidizable to a persistent C70(CF3)15· radical. Together with the literature data for the lower C70(CF3)n compounds with n=2–12, the present results show good correlation between the experimental boundary level positions and the DFT predictions. The compounds turn out to be electron acceptor molecular semiconductors with experimental LUMO energies and HOMO–LUMO gaps within the ranges of ?4.3 to ?3.7 eV and 1.6 to 3.3 eV, respectively, depending on the shape of the conjugated fragments. The HOMO levels fall within the range of ?5.6 to ?6.9 eV and show linear correlation with the number of addends. 相似文献
4.
Orienting Effect of the Cage Addends: The Case of Nucleophilic Cyclopropanation of C2‐C70(CF3)8 下载免费PDF全文
Dr. Marina G. Apenova Olesya O. Semivrazhskaya Eugenia V. Borkovskaya Nikita M. Belov Dr. Ilya N. Ioffe Dr. Vitaliy Yu. Markov Prof. Dr. Sergey I. Troyanov Dr. Natalia S. Lukonina Prof. Dr. Lev N. Sidorov Dr. Alexey A. Goryunkov 《化学:亚洲杂志》2015,10(6):1370-1378
C2‐C70(CF3)8 was found to be a very promising substrate in the Bingel and the Bingel–Hirsch reactions combining perfect regioselectivity with much higher reactivity compared to its analogs. The reactions with diethyl malonate yield a single isomer of the monoadduct C70(CF3)8[C(CO2Et)2] and a single C2‐symmetrical bisadduct C70(CF3)8[C(CO2Et)2]2. The Bingel–Hirsch variation is particularly interesting in that it additionally affords, in a similar regioselective manner, the unexpected alkylated derivatives C70(CF3)8[CH(CO2Et)2]H and C70(CF3)8[C(CO2Et)2][CH(CO2Et)2]H. The novel compounds have been isolated and structurally characterized by means of 1H and 19F NMR spectroscopy as well as single‐crystal X‐ray diffraction. The mechanistic and regiochemical aspects of the reaction are explained with the aid of DFT calculations. 相似文献
5.
Petrova Alena S. Lukonina Anna A. Dementyev Dmitry V. Ya. Bolsunovsky Alexander Popov Anatoliy V. Kudryasheva Nadezhda S. 《Analytical and bioanalytical chemistry》2018,410(26):6837-6844
Analytical and Bioanalytical Chemistry - The study suggests an application of a coelenteramide-containing fluorescent protein (CLM-CFP) as a simplest bioassay for gamma radiation exposures.... 相似文献
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7.
Victor A. Brotsman Viktor P. Bogdanov Alexey V. Rybalchenko Evgenia P. Galanicheva Nikita M. Belov Dr. Vitaliy Yu. Markov Dr. Natalia S. Lukonina Dr. Ilya N. Ioffe Prof. Dr. Sergey I. Troyanov Prof. Dr. Erhard Kemnitz Dr. Alexey A. Goryunkov 《化学:亚洲杂志》2016,11(13):1945-1954
CF3‐derivatized fullerenes prove once again to be promising scaffolds for regioselective fullerene functionalization: now with the smallest possible addends—hydrogen atoms. Hydrogenation of Cs‐C70(CF3)8 and C1‐C70(CF3)10 by means of reduction with Zn/Cu couple in the presence of water proceeds regioselectively, yielding only one major isomer of C70(CF3)8H2 and only two for C70(CF3)10H2, whose addition patterns are combined in the only abundant isomer of C70(CF3)10H4. The observed selectivity is governed by the electronic structure of trifluoromethylated substrates. Interestingly, we discovered that Clar's theory can be utilized to predict the regiochemistry of functionalization, and we look forward to testing it on forthcoming cases of derivatization of pre‐functionalized fullerene building blocks. 相似文献
8.
Prof. Dr. Alexey A. Goryunkov Dr. Nail L. Asfandiarov Rustam G. Rakhmeev Angelina V. Markova Dr. Stanislav A. Pshenichnyuk Alexey V. Rybalchenko Dr. Natalia S. Lukonina Prof. Dr. Ilya N. Ioffe 《Chemphyschem》2022,23(10):e202200038
Gas phase molecules of hexachlorobenzene (C6Cl6) were investigated by means of dissociative electron attachment spectroscopy (DEAS). Three channels of molecular negative ions decay have been identified: abstraction of Cl− and Cl2− as well as electron detachment (τa∼250 μs at 343 K). All three channels exhibit temperature dependence. The adiabatic electron affinity estimated using a simple but typically accurate Arrhenius model (EAa=1.6–1.9 eV) turns out to be much higher than the quantum-chemical predictions (EAa=0.9–1.0 eV). We discuss the possible reasons behind the observed discrepancy. 相似文献
9.
V. A. Loskutov S. M. Lukonina A. V. Konstantinova E. P. Fokin 《Chemistry of Heterocyclic Compounds》1978,14(8):915-919
It is shown that 2,3,4,5-tetrahydro-1H-naphtho[2,3-b]-1,4-diazepine-2,4,6,11-tetraone, which has acid properties, undergoes methylation to give an N,N-di-methyl derivative, whereas it gives products of substitution of the hydrogen atoms of the methylene group in its reactions with bromine and salicylaldehyde. Treatment of 2,3,4,5-tetrahydro-1H-naphtho[2,3-b]-1,4-diazepine-2,4,6,11-tetrone with aqueous alkali or secondary aliphatic amines with heating is accompanied by opening of the diazepine ring to give hydrolysis (2-carboxyacetamido-3-hydroxy-1,4-naphthoquinones) or aminolysis (N-alkylaminomalonyl-2,3-diamino-1,4-naphthoquinones) products.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1132–1136, August, 1978. 相似文献
10.
Alkali‐Metal Trichloroacetates for Dichloromethylenation of Fullerenes: Nucleophilic Addition‐Substitution Route 下载免费PDF全文
Marina G. Apenova Vladimir A. Akhmetov Nikita M. Belov Dr. Alexey A. Goryunkov Dr. Ilya N. Ioffe Dr. Natalia S. Lukonina Dr. Vitaliy Yu. Markov Prof. Dr. Lev N. Sidorov 《化学:亚洲杂志》2014,9(3):915-923
The first experimental evidence that fullerenes react with alkali‐metal trichloroacetates through a nucleophilic addition‐substitution route, yielding dichloromethylenefullerenes as the final products, is reported. The intermediates, C60(CCl3)? and C70(CCl3)? anions, have been isolated in their protonated forms as ortho‐C60(CCl3)H, as well as three ortho and one para isomer of C70(CCl3)H. The structures were unambiguously determined by means of 1H, 13C, and 1H–13C HMBC NMR spectroscopy along with UV/Vis spectroscopy. The observed regiochemistry was analyzed with the aid of quantum chemical calculations. Conversion of the protonated compounds into the [6,6]‐closed C60/70(CCl2) cycloadducts under basic conditions can be effected only for the ortho isomers, whereas para‐C70(CCl3)H decomposes back into pristine C70. 相似文献