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1.
G. B. Guseva E. V. Antina A. I. Vyugin 《Journal of Thermal Analysis and Calorimetry》2008,92(3):735-737
3,3′,4,4′-tetramethyl-5,5′-dicarboethoxydipyrrolylmethane-2,2′ and its α,β and β,β′ isomers were synthesized. The compounds
were characterized by recording of their proton NMR spectra. The thermal oxidative destruction of the compounds was studied
by thermogravimetry. The thermal stability of dipyrrolylmethanes was found to be primarily characterised by molecular isomerism
for symmetrically substituted α,α′-and β,β′-dipyrrolylmethanes compared with α,β isomer. 相似文献
2.
I. S. Levina L. E. Kulikova E. V. Shulishov I. P. Klimenko A. V. Kamernitskii Yu. V. Tomilov 《Russian Chemical Bulletin》2006,55(11):2119-2121
4′,4′-Dimethyl[16α,17α]spiropentanopregn-4-ene-3,20-dione was synthesized. The addition of diazo-2,2-dimethylcyclopropane
generated from N-(2,2-dimethylcyclopropyl)-N-nitrosourea to 16,17-didehydropregnenolone acetate occurs regio-and stereospecifically to give 3β-acetoxy-1′,1′-dimethyl-20-oxopregn-5-ene-[16α,17α;7′,6′]-4′,
5′-diazaspiro[2.4]-hept-4′-ene in high yield. Its thermolysis affords a spiropentane-containing steroid, which is transformed
into the target diketone. The anti position of the gem-dimethyl group in the fused spiropentane fragment is evident from the X-ray diffraction study of the final product.
Dedicated to Academician O. M. Nefedov on the occasion of his 75th birthday.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2040–2042, November, 2006. 相似文献
3.
V. Yu. Mortikov Yu. M. Litvinov A. A. Shestopalov L. A. Rodinovskaya A. M. Shestopalov 《Russian Chemical Bulletin》2008,57(11):2373-2380
A versatile method for the synthesis of 2′-amino-1,2-dihydrospiro[(3H)-indole-3,4′-(4′H)-pyran]-2-ones has been suggested consisting in the three-component reaction of isatins, cyanoacetic acid derivatives, and
α-methylenecarbonyl compounds (β-dicarbonyl compounds, activated phenols, and OH-substituted heterocycles) in ethanol in the
presence of triethylamine as a catalyst. The reaction proceeds selectively to form spiro[(3H)-indole-3,4′-(4′H)-pyrans]. 相似文献
4.
Rajarshi Chatterjee Mahammad Ali Michael G. B. Drew M. Nethaji Swastik Mondal Monika Mukherjee 《Transition Metal Chemistry》2009,34(1):1-5
Blue [{Cu(2,2′-bipy)2}2{α-SiW12O40}] (bipy = bipyridyl) (1) and pale yellow [Mn(2,2′-bipy)3]2[α-SiW12O40] (2) have been synthesized hydrothermally and characterized by IR spectroscopy and single crystal X-ray structure analysis. In
1, the [α-SiW12O40]4− ion acts as a bridge between the two [{Cu(2,2′-bipy)2]2+ moieties via coordination through the terminal oxygen atoms, while in 2, the [Mn(2,2′-bipy)3]2+ ion balances the charge on the polyoxo anion without forming any covalent bond. To the best of our knowledge, this is the
first example of transition metal-mediated transformation of [α-SiW9O34]10− to [α-SiW12O40]4−.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
5.
S. S. Mochalov N. A. Puretskii A. N. Fedotov E. V. Trofimova V. A. Tafeenko L. A. Aslanov N. S. Zefirov 《Russian Journal of Organic Chemistry》2012,48(1):40-51
3,4: 3′,4′-Bis(ethylenedioxy)biphenyl undergoes bromination, nitration, and cyclopropylcarbonylation only at the 2-position.
Analogous reactions with 2-substituted bis(ethylenedioxy)biphenyls occur regioselectively at the 2′-position. The reactions
of 2-cyclopropylcarbonyl- and 2,2′-bis(cyclopropylcarbonyl)bis(ethylenedioxy)biphenyls with complex metal hydrides afforded
the corresponding arylcyclopropylcarbinols which tended to undergo intramolecular alkylation of the aromatic ring with conservation
of the cyclopropane fragment (monosubstituted derivatives) and formation of cyclopropyl-containing cyclic ethers (disubstituted
ethylenedioxybiphenyls). The reduction of the nitro group in 2′-cyclopropylcarbonyl-2-nitro-4,5: 4′,5′-bis(ethylenedioxy)biphenyl
was accompanied by intramolecular cyclization involving spatially close functional groups, the cyclopropane fragment remaining
intact. 相似文献
6.
Three novel heteropolytungstates, [Cu(phen)2]4[α-SiW12O40] (1), [Cu4(4,4′-bpy)3(2,2′-bpy)4][α-SiW12O40] · H2O (2) and [Cu(4,4′-bpy)(4,4′-Hbpy)0.5]2[PW12O40] (3) (phen = 1,10-phenanthroline, 4,4′-bpy = 4,4′-bipyridine, 2,2′-bpy = 2,2′-bipyridine), have been synthesized and characterized
by elemental analyses, IR, TG analyses and single-crystal X-ray diffraction. Compound (1) exhibits interesting chiral layer constructed from interperpendicular helical chains running along a crystallographic 21 axis in the c and a directions. Furthermore, the chiral layers are connected by the [α-SiW12O40]4− anions via hydrogen bonding interactions to form a 3D superamolecular structure. The [Cu4(4,4′-bpy)3(2,2′-bpy)4]4+ coordinated complexes in compound (2) are packed together via the aromatic π–π stacking interactions and exhibit an interesting 3D sandglasslike “host” network with 1D channels, in which
[α-SiW12O40]4− anions “guests” reside. Compound (3) has a unique 2D superamolecular network, which is composed of cationic CuI coordination polymer chains and discrete [PW12O40]3− polyoxoanions as linkers. It is noteworthy that the monprotonated 4,4′-bpy ligands of (3) act as arms and connect the adjacent 2D network, generating a 3D interpenetrating superamolecular structure. 相似文献
7.
Yu. N. Belokon’ S. Ch. Gagieva T. A. Sukhova A. B. Dmitriev K. A. Lyssenko N. M. Bravaya B. M. Bulychev D. Seebach 《Russian Chemical Bulletin》2005,54(10):2348-2353
Titanium complexes of chiral ligands, (4R,5R)-2,2-dimethyl-α,α,α′,α′-tetraphenyl-1,3-dioxolane-4,5-dimethanol and its structural analogs, activated by polymethylalumoxane
catalyze ethylene polymerization with an activity from 3 to 530 (kg polyethylene) (mol Ti h atm)−1. An increase in the bulk of the aryl substituents results in a decrease in the catalytic activity of the complexes.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2275–2280, October, 2005. 相似文献
8.
Polystyrene supported Rh(I) AA′ (AA′ = anthranilic acid, 2,2′-bipyridine or 1,10-phenanthroline) complexes catalyse the hydrogenation
of monoolefins (terminal, cyclic and internal) and dienes. Ethyl sorbate undergoes saturation via the monoene intermediate.
Thiscis olefin reacts faster than thetrans isomer. The rate law for the reaction is: Rate α [catalyst] [substrate] [H2]. 相似文献
9.
Mokrov G. V. Likhosherstov A. M. Lezina V. P. Gudasheva T. A. Bushmarinov I. S. Antipin M. Yu. 《Russian Chemical Bulletin》2010,59(6):1254-1266
The reactions of methyl α-(2-formyl-1H-pyrrol-1-yl)carboxylates with N-substituted aliphatic 1,2-, 1,3-, and 1,4-diamines afford new pyrrole-containing heterocyclic systems: 1,2,3,10b-tetrahydroimidazo[1,2-a]pyrrolo[2,1-c]pyrazin-5(6H)-ones, 1,3,4,11b-tetrahydro-2H-pyrrolo[2′,1′:3,4]pyrazino[1,2-a]pyrimidin-6(7H)-ones, and 1,2,3,4,5,12b-hexahydro-pyrrolo[2′,1′:3,4]pyrazino[1,2-a][1,3]diazepin-7(8H)-ones. The reduction of these compounds with different reagents was studied. 相似文献
10.
V. V. Shchepin Yu. G. Stepanyan P. S. Silaichev M. A. Ezhikova M. I. Kodess 《Russian Journal of Organic Chemistry》2010,46(4):499-502
Bromine-containing organozinc compounds generated from 1,1-dibromo-3,3-dimethylbutan-2-one reacted with 2-arylmethylideneindan-1,3-diones
and 5-arylmethylidene-2,2-dimethyl-1,3-dioxane-4,6-diones to give 3-aryl-2-(2,2-dimethylpropanoyl)spiro[cyclopropane-1,2′-indan]-1′,3′-diones
and 1-aryl-6,6-dimethyl-2-(2,2-dimethylpropanoyl)-5,7-dioxaspiro[2.5]octan-4,8-diones, respectively. Reactions of 2-arylmethylideneindan-1,3-diones
with bromine-containing zinc enolates derived from 1-aryl-2,2-dibromopropan-1-ones and 2,2-dibromo-1,2,3,4-tetrahydronaphthalen-1-one
resulted in the formation of 2-aroyl-3-aryl-2-methylspiro-[cyclopropane-1,2′-indan]-1′,3′-diones and 2,3: 8,9-dibenzo-12-phenyldispiro[4.0.5.1]dodecane-1,4,7-trione,
respectively. 相似文献
11.
I. N. Stan’kov I. D. Derevyagina Yu. A. Karpel’tseva V. I. Selivanova S. V. Sadovnikov 《Journal of Analytical Chemistry》2011,66(2):189-194
A procedure is developed for the separate determination of microquantities of iprite (2,2′-dichlorodiethylsulfide) and α-lewisite
(2-chlorovinyldichloroarsine) in bituminous masses formed in the bitumenation of iprite-lewisite crude mixtures in objects
of the destruction of chemical weapons. The concentration range is (2–20) × 10−4%. 相似文献
12.
Imre Labádi Mária Benk Kata Markó István Szilágyi 《Reaction Kinetics and Catalysis Letters》2009,96(2):327-333
Mimicking the Superoxide Dismutase Enzyme (SOD), several imidazolato-bridged copper(II)-zinc(II) complexes were prepared,
characterised by IR spectroscopy and their SOD enzyme activity was determined. 2,2′-Bipyridine, 2,2′:6′,2″-terpyridine and
tris(2-aminoethyl)amine molecules were used on both metal sides, as coordinating ligands. The complex, containing the 2,2′:6′,2″-terpyridine
ligand on copper side has the smallest SOD activity, which indicates the importance of the rigidity of the copper complex
in SOD activity. 相似文献
13.
Qiang Li Pingfan Wu Panchao Yin Jin Zhang Lu Shi Yongge Wei 《Journal of Cluster Science》2010,21(2):181-186
The α-octamolybdate-supported compound: [Fe(2,2′-bipy)3]2[α-Mo8O26] has been unexpectedly synthesized during a diffuse process and characterized by the IR spectroscopy, UV–Vis diffuse reflectance
spectroscopy and the single crystal X-ray diffraction. The title compound exhibits an interesting 3D honeycomb ‘host’ supramolecular
network with 1D channels, in which only α-octamolybdate anions ‘guests’ reside. The title compound shows the anisotropic property
and probably will be applied as a novel semiconductor in the future. 相似文献
14.
The absorption spectra in dilute dichloromethane solution at 300 K of four Oligotiophenes (OT), namely 2,2′:5′,2″-Terthiophene,
2,2′:5′,2″:5″,2″′-Quaterthiophene, 4,4″′-Didodecyl-2,2′:5′,2″:5″,2″′-quaterthiophene and 5,5′′′′′-Dihexyl-2,2′:5′,2′′:5′′,2′′′:5′′′,2′′′′:5′′′′,2′′′′′-sexithiophene,
have been studied both experimentally and theoretically by using a combination of molecular dynamics simulations, time-dependent
density functional theory (TD-DFT) and perturbed matrix method calculations. A deep analysis of the theoretical results, affected
by a systematic although not dramatic underestimation of the absorption maxima due to the well-documented TD-DFT limitations,
clearly indicates that both the environmental (solvent) and thermal effects significantly alter the Oligotiophenes photophysical
properties mainly because of the wide repertoire of the S0–S1 energy gaps and electronic densities experienced in solution by the different conformers actually populated. In particular,
all the investigated OT display a very high flexibility resulting in a very high repertoire of sampled conformations. The
comparison of the calculated and experimental lineshape of the S0–S1 electronic transition has clearly indicated that for a correct modeling of OT spectral features, the lack of an exhaustive
sampling of semiclassical configurational space of the overall system, i.e., solute in interaction with the solvent, might
result in an incomplete picture even in the presence of well-documented important aspects such as reliable definition of excited
electronic states and the inclusion of quantum vibronic effects. 相似文献
15.
E. I. Mayboroda Yu. L. Slominsky A. V. Turov A. I. Tolmachev 《Chemistry of Heterocyclic Compounds》2008,44(1):78-85
Tetramethylene-2,2′-bis(1,3,3-trimethyl-(3H)-indolium),-3-ethylbenzothiazolium,-1-methyl-quinolinium, and-1-methyl-and-1-butylbenz[c,d]indolium
salts were synthesized starting from them trimethinecyanines containing an ethylene bridging group in the α, α′-positions
of the chromophore have been prepared. These compounds are converted to their analogs containing a vinylene group by the action
of benzoquinones. In the case of thiacarbocyanines the effect of the indicated bridging groups on the conformation and protonation
route of the carbocyanines has been studied. The chromaticity of the dyes has been investigated.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 94–102, January, 2008. 相似文献
16.
Eri Yoshida 《Colloid and polymer science》2010,288(3):341-345
In order to clarify the initiator factor dominating the molecular weight distribution of the resulting polymer, the nitroxide-mediated
photo-living radical polymerization of methyl methacrylate was performed using eight different kinds of azoinitiators: i.e.,
2,2′-azobisisobutyronitrile, 2,2′-azobis(2-methylbutyronitrile), 2,2′-azobis(2,4-dimethylvaleronitrile), 1,1′-azobis(cyclohexane-1-carbonitrile),
racemic-(2RS,2′RS)-azobis(4-methoxy-2,4-dimethylvaleronitrile), meso-(2RS,2′SR)-azobis(4-methoxy-2,4-dimethylvaleronitrile),
dimethyl 2,2′-azobis(2-methylpropionate), and 2,2′-azobis(N-butyl-2-methylpropionamide). The bulk polymerization was carried out at room temperature for 3 h using 4-methoxy-2,2,6,6-tetramethylpiperidine-1-oxyl
(MTEMPO) as the mediator in the presence of bis(alkylphenyl)iodonium hexafluorophosphate as the photo-acid generator. All
the initiators provided a molecular weight distribution below 1.7 for the MTEMPO/initiator ratio of 2, although at the ratio
of unity, about half of the initiators produced the molecular weight distribution around 2.3–3.4. The UV analysis revealed
that the initiators having a higher ε value tended to more strictly control the molecular weight and provide a higher initiator
efficiency. The half-lives of the initiators had little effect on the molecular weight control and initiator efficiency. 相似文献
17.
Lutz Preu Wolfgang Kliegel Steven J. Rettig James Trotter 《Monatshefte für Chemie / Chemical Monthly》2001,132(10):1213-1224
Summary. The structure of the dehydrogenation product 1′,3a′-dihydro-3′-((1,3-dioxoindan-2-ylidene)-phenyl-methyl)-5′-phenyl-spiro-(indan-2,1′-pyrrolo[3,4-c]pyrrole)-1,3,4′,6′-(5′H, 6a′H)-tetrone derived from the cycloadducts (±)-(3a′S,6a′R)-1′,3a′-dihydro-3′-((R)-α-(1,3-dioxoindanyl)-benzyl)-5′-phenyl-spiro-(indan-2,1′-pyrrolo[3,4-c]pyrrole)-1,3,4′,6′(5H,6a′H)-tetrone and/or (±)-(3a′S,6a′R)-1′,3a′-dihydro-3′-((S)-α-(1,3-dioxoindanyl)-benzyl)-5′-phenyl-spiro-(indan-2,1′-pyrrolo[3,4-c]pyrrole)-1,3,4′,6′(5H,6a′H)-tetrone, which were synthesized by 1,3-dipolar cycloaddition of N-phenylmaleimide to 2-((2-(1,3-dioxoindan-2-yl)-2-phenyl-ethenyl)-imino)-indan-1,3-dione,
was determined by X-ray analysis. Crystal data (CCD, 180 K): rhombohedral, R&3macr;;, a = 34.0871(7), c = 13.9358(5) ?, Z = 18; the structure was solved by direct methods and refined by full-matrix least-squares procedures to R(F, I ≥ 3σ(I)) = 0.053. The molecule contains a central folded ring system of two cis-fused 5-membered heterocyclic rings; each ring is nearly planar, and the angle between the rings amounts to 59.0°. Dynamic
1H NMR spectroscopy of the product revealed an exchange process caused by restricted rotation of the double bonded 1,3-indandione
moiety and the phenyl group about the Csp2-Csp2 single-bonds. Molecular modeling and complete lineshape analysis indicated a four site exchange process for which free energies
of activation and free energies could be established. ΔG
‡ values for the barriers of rotation are in the range of 57–59 kJ · mol − 1 at 273 K, which is unusually high for an unsubstituted phenyl group.
Received May 3, 2001. Accepted (revised) June 8, 2001 相似文献
18.
A. V. Velikorodov O. Yu. Poddubnyi A. K. Kuanchalieva O. O. Krivosheev 《Russian Journal of Organic Chemistry》2010,46(12):1826-1829
1,3-Dipolar cycloaddition to methyl 4-[2-(2-oxo-2,3-dihydro-1H-indol-3-ylidene)-1-oxoethyl]-phenylcarbamate of diazomethane in chloroform-diethyl ether and of 3,4-dimethoxybenzonitrile
oxide generated from the corresponding aldehyde oxime by the action of N-chlorobenzenesulfonamide sodium salt (Chloramine B) in boiling ethanol gave, respectively, methyl 4-(2-oxo-1′,5′-dihydro-1H-spiro[indole-3,4′-pyrazol]-3′-ylcarbonyl)phenylcarbamate and methyl 4-[3′-(3,4-dimethoxyphenyl)-2-oxo-1H,4′H-spiro[indole-3,5′-isoxazol]-4′-ylcarbonyl]phenylcarbamate. The condensation of methyl 4-[2-(2-oxo-2,3-dihydro-1H-indol-3-ylidene)-1-oxoethyl]phenylcarbamate with hydrazine hydrate in ethanol afforded methyl 4-(2-oxo-1,2,2′,4′-tetrahydrospiro[indole-3,3′-pyrazol]-5′-yl)phenylcarbamate. 相似文献
19.
V. Keshava Rao T. Jaganmohana Chary A. Krishna Murthy 《Journal of Chemical Sciences》1992,104(5):569-576
Sunlight photolysis of 4,5-diphenylisoxazole (1) in methanol sensitized by benzophenone gives 4,4′,5,5′-tetraphenyl-2,2′-bioxazole, (4). On irradiation at 350nm in acetone or at 253.7 nm in absolute alcohol, isoxazole (1) yields α-benzoylphenylacetonitrile (6) besides the expected phenanthro [9,10-d]-oxazole (5). The bioxazole and the ketonitrile have been identified by single crystal X-ray studies. 相似文献
20.
A trimethoxy derivative with three nonequivalent methoxy groups was obtained from 2,2′, 4-trichloro-6′-phenyl-4′ 5-dipyrimidinyl.
Rearrangement of 2,2′, 4-trimethoxy-6′-phenyl-4′, 5-dipyrimidinyl under Hubert-Johnson conditions and thermal rearrangement
with and without a catalyst make it possible to obtain 2′,4-dimethoxy-1-methyl-2-oxo-and 2′-methoxy-1,3-dimethy1-2,4-dioxodipyrimidinyls
and both tri-N-methyl isomers, viz., the 1,1′, 3-and 1,3,3′-trimethyl derivatives. The possibility of obtaining N-methyl derivatives
of trioxodipyrimidinyl by methylation under various conditions was also examined.
See [1] for communication 70.
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 398–403, March, 1980. 相似文献