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1.
Equilibrium structural parameters, dipole moments, relative energies, vibration spectra, and ionization potentials of various
conformers of benzoid (B), p- and o-quinoid (Q), and deprotonated anionic forms of vanillin in a vacuum and in a polarizable medium with dielectric properties
of water were calculated by the quantum-chemical method (U)B3LYP/cc-pVTZ. The intramolecular hydrogen bond in free vanillin
benzoid molecule B1 is characterized by the energy of 4 kcal mol−1 and by the barrier of cleavage 8 kcal mol−1 that correspond to the conformational transition B1 → B2. The energy of the optimal p-quinoid conformer (Q1) is 22 kcal mol−1 larger than the energy of B1 in a vacuum and 15 kcal mol−1 in water. The p-quinoid forms greatly exceeds the benzoid forms by dipole moment, electrophilicity, and nucleophilicity. The structure calculated
for the anion is intermediate between benzoid and p-quinoid forms, and the calculated energy of polarization stabilization in water is 57 kcal mol−1. 相似文献
2.
G. A. Abakumov V. K. Cherkasov A. V. Krashilina I. L. Eremenko S. E. Nefedov 《Russian Chemical Bulletin》1998,47(11):2262-2270
New mononuclear 3,6-di-tert-butyl-o-benzosemiquinone complexes of copper(1) with bis(diphenylphosphine) ligands were synthesized: (DBSQ)Cu(dppe) (1) (DBSQ=3,6-di-tert-butyl-o-benzosemiquinone and dppe=1,2-bis(diphenylphosphino)ethane), (DBSQ)Cu(dppp) (2) (dppp=1,3-bis(diphenylphosphino)propane), (DBSQ)Cu(dppn) (3) (dppn=2,2′-bis(diphenylphosphino)-1,1′-binaphthyl), and (DBSQ)Cu(dppfc) (4) (dppfc=1,1′-bis(diphenylphosphino)ferrocene). The compositions and structures of complexes1–4 were characterized by elemental analysis and electronic absorption, IR, and ESR spectroscopy. The molecular structures of
complexes3 and4 were established by X-ray diffraction analysis. The reactions of elimination and replacement of neutral ligands in the coordination
sphere of the complexes were studied by ESR spectroscopy.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2333–2340, November, 1998. 相似文献
3.
A. L. Kurlovich V. A. Tarasevich N. G. Kozlov 《Russian Journal of Organic Chemistry》2009,45(10):1503-1508
Condensation of 2′-hydroxy-1,1′: 3′,1″-terphenyl-5′-carbaldehyde with naphthalen-1-amine and cyclohexane-1,3-dione, methyl
2,2-dimethyl-4,6-dioxocyclohexane-1-carboxylate, or dimedone gave the corresponding 7-(2′-hydroxy-1,1′: 3′,1″-terphenyl-5′-yl)-7,8,9,10,11,12-hexahydro-12H-benzo[c]acridin-8-ones. The reaction of 2′-hydroxy-1,1′: 3′,1″-terphenyl-5′-carbaldehyde with naphthalen-1-amine and indan-1,3-dione
produced 7-(2′-hydroxy-1,1′: 3′,1″-terphenyl-5′-yl)-8H-benzo[h]indeno[1,2-b]quinolin-8-one. 7-(2′-Hydroxy-1,1′: 3′,1″-terphenyl-5′-yl)-7,8,9,10,11,12-hexahydrobenzo[b][1,10]phenanthrolin-8-ones were obtained by three-component condensation of 2′-hydroxy-1,1′: 3′,1″-terphenyl-5′-carbaldehyde
with quinolin-8-amine and cyclohexane-1,3-dione, methyl 2,2-dimethyl-4,6-dioxocyclohexane-1-carboxylate, or dimedone. 相似文献
4.
Andrei V. Bogdanov Vladimir F. Mironov Lenar I. Musin Rashid Z. Musin Dmitry B. Krivolapov Igor A. Litvinov 《Monatshefte für Chemie / Chemical Monthly》2011,41(3):81-85
Abstract
The reaction of aminomethylisatins (isatin N-Mannich bases) with hexaethylphosphorous triamide leads to the formation of 1,1′-bis(dialkylaminomethyl)-3,3′-bis(indolin-3-ylidene)-2,2′-diones and 1,1′-bis(1,3-dioxo-1,3-dihydroisoindol-2-ylmethyl)-1H,1′H-[3,3′]bisindolylidene-2,2′-dione. 相似文献5.
Natalia Fridman Moshe Kapon Yana Sheynin Menahem Kaftory 《Journal of inclusion phenomena and macrocyclic chemistry》2006,54(3-4):153-157
1,3-Benzenediamine,N,N′-bis(4,6-dichloro-1,3,5-triazine-2-yl) and 1,3,5-Triazine,2,2′-[2-methyl-1,3-phenylenebis(oxy)] bis(4,6-dichloro) were synthesized as host molecules. The inclusion compound of 1,3-Benzenediamine,N,N′-bis(4,6-dichloro-1,3,5-triazine-2-yl) crystallizes in the monoclinic crystal system in space group C2/c. The host molecule occupies the space group 2-fold special position and packed in the crystal lattice in such a manner as to leave channels running along the c axis of a rectangular cross-section. It crystallizes with two molecules of acetone that are hydrogen bonded to the amino nitrogen atoms. Molecules of 1,3,5-Triazine,2,2′-[2-methyl-1,3-phenylene bis(oxy)]bis(4,6-dichloro) are packed in the crystal in such a manner as to leave channels of a trapezoid cross-section that are running along the a axis. Guest molecules such as metanol, ethanol, and ethyl acetate can be used to fill the channels. The crystal structures of two inclusion compounds are described. 相似文献
6.
Matthew L. Milling Jermaine Cooley Dmitriy V. Liskin Edward J. Valente 《Structural chemistry》2009,20(6):969-973
Abstract
Oxidation of 1,4-bis(4′-oxo-2′,2′-dimethylpent-2-yl)benzene with hypochlorite produces 1,4-bis(3′-carboxy-2′-methylbut-2-yl)benzene and 3-(4′-carboxyphenyl)-3,3-dimethylpropanoic acid. Cyclization of this mixture forms 3,3,7,7-tetramethyl-1,2,3,5,6,7-hexahydro-s-indacen-1,5-dione, 3,3,7,7-tetramethyl-1,2,3,5,6,7-hexahydro-as-indacen-1,5-dione (5) and 6-carboxy-3,3-dimethyl-1-indanone (6). Ketoacid (6) is converted to the arylpyran pseudoacid 7-carboxy-3-hydroxy-4,4-dimethylisobenzopyran-1-one (7). In the crystal structure of (7), carboxylic acid and the pseudoacid groups each form complementary dimer hydrogen bonds linking the molecules in chains. Contact O···O distances reflect their differing energetics, with pseudoacyl O···O at 2.78(1)Å and carboxylic O···O at 2.62(1)Å. 相似文献7.
V. A. Mamedov A. A. Kalinin A. T. Gubaidullin I. A. Litvinov 《Russian Chemical Bulletin》2007,56(12):2471-2478
Bis-3-(α-bromoethyl)quinoxalin-2-ones with 3-oxapentane or 3,6-dioxaoctane spacer binding two heterocyclic fragments react
with thiourea to give the corresponding bis-spirothiazoloquinoxalines, which upon treatment with acetic anhydride can be converted
to podands with terminal thiazoloannulated quinoxaline fragments. X-Ray data for 2′-amino-4-ethyl-5-methyl-1,2,3,4,4′,5′-hexahydrospiro[quinoxaline-2,4′-thiazol]-3-one
indicate for this compound a potentiality to form clathrate structures with various solvate molecules.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2386–2393, December, 2007. 相似文献
8.
Rong-Ho Lee Tun-Fang Cheng Jhih-Wei Chang Jhu-Heng Ho 《Colloid and polymer science》2011,289(7):817-829
In this study, a series of gel electrolytes prepared from blends of alternating conjugated polymer electrolytes (CPEs)/poly(ethylene
oxide) (PEO) were developed for use in quasi-solid-state dye-sensitized solar cells (DSSCs). The alternating CPEs poly[(N-(3′-((N,N-dimethyl)-N-ethylammonium)propyl)-3,6-carbazole)-alt-(9,9-dioctyl-2,7-fluorene)]diiodide, poly[(N-(3′-((N,N-dimethyl)-N-ethylammonium)propyl)-3,6-carbazole)-alt-(9,9-bis(2-(2-methoxyethoxy)ethyl)-2,7-fluorene)]diiodide (MPCFO-E), and poly[(N-(3′-((N,N-dimethyl)-N-ethylammonium)propyl)-3,6-carbazole)-alt-(siloxane substituted-2,7-fluorene)]diiodide (MPCFS-E) were synthesized through copolymerization of carbazole units (featuring
quaternized ammonium iodide groups) and fluorene units featuring flexible side chains (9,9-dioctylfluorene, ethylene oxide-substituted
fluorene, and siloxane-substituted fluorene, respectively). The MPCFO-E/PEO-based and MPCFS-E/PEO-based DSSCs exhibited lower
electrochemical resistances, superior photovoltaic (PV) properties, and improved PV stabilities relative to those of the corresponding
PEO-based DSSC. Among the studied systems, the DSSC based on the MPCFO-E (0.5 wt.%)/PEO blend electrolyte exhibited the best
PV performance, with a short current density of 4.97 mA cm−2 and a photoenergy conversion efficiency of 1.17%. 相似文献
9.
Cyclopentanone or cyclohexanone were condensed with aromatic aldehydes to give corresponding α,α′-bis(R-benzylidene)cyclopentanones or α,α′-bis(R-benzylidene)cyclohexanones. The reaction was catalyzed by potassium hydrogen sulfate with a yield of 84–95% under
solvent-free conditions. 相似文献
10.
M. Aksu S. Durmu M. Sari K. C. Emregül I. Svoboda H. Fuess O. Atakol 《Journal of Thermal Analysis and Calorimetry》2007,90(2):541-547
N,N′-bis(salicylidene)-1,3-propanediamine (LH2), N,N′-bis(salicylidene)-2,2′-dimethyl-1,3-propanediamine (LDMH2), N,N′-bis(salicylidene)-2-hydroxy-1,3-propanediamine (LOH3), N,N′-bis(2-hydroxyacetophenylidene)-1,3-propanediamine (LACH2) and N,N′-bis(2-hydroxyacetophenone)-2,2′-dimethyl-1,3-propanediamine (LACDMH2) were synthesized and reduced to their phenol-amine form in alcoholic media using NaBH4 (LHH2, LDMHH2, LOHHH2, LACHH2 and LACDMHH2). Heterodinuclear complexes were synthesized using Ni(II), Zn(II) and Cd(II) salts, according to the template method in DMF
media.
The complex structures were analyzed using elemental analysis, IR spectroscopy, and thermogravimetry. Suitable crystals of
only one complex were obtained and its structure determined using X-ray diffraction, NiLACH·CdBr2·DMF2, space group orthorhombic, Pbca, a=20.249, b=14.881, c=20.565 ? and Z=8. The heterodinuclear complexes were seen to be of [Ni·ligand·MX2·DMF2] structure (ligand=LH2−, LDMH2−, LOHH2−, LACH2−, LACDMH2−, M=ZnII, CdII, X=Br−, I−). Thermogravimetric analysis showed irreversible bond breakage of the coordinatively bonded DMF molecules followed by decomposition
at this temperature. 相似文献
11.
V. B. Vol’eva A. I. Prokof’ev I. S. Belostotskaya A. Yu. Karmilov N. L. Komissarova T. I. Prokof’eva V. V. Ershov 《Russian Journal of Electrochemistry》2000,36(6):847-850
Solid-phase oxidation of 2,4-di-tert-butylphenol to give 2,2′,4,4′-tert-butyl-6,6′-bisphenol and of 3,6-di-tert-butylpyrocatechol to afford 3,6-di-tert-butyl-l,2-benzoquinone was performed in the presence of alkali and alkaline earth metals halides under conditions of modified
extrusion. The formation of the corresponding metal 3,6-di-tert-butylsemiquinolates was registered by ESR method. The different behavior of chlorides, bromides, and iodides was observed
and rationalized basing on the dissimilar complexing ability of halogens. The mechanism of activated oxidation was assumed.
The study was carried out under financial support of the Russian Foundation for Basic Research (grant no. 96-03-33253a).
Deceased. 相似文献
12.
V. F. Mironov L. M. Burnaeva Yu. Yu. Borisova A. T. Gubaidullin I. A. Litvinov G. A. Ivkova I. V. Konovalova 《Russian Journal of Organic Chemistry》2011,47(10):1521-1526
Reactions of 2-phenyl-4,4-bis(trifluoromethyl)-4,5-dihydro-1,3,2-benzodioxaphosphepin-5-one with 9,10-phenanthrenequinone
and dibenzoyl gave hydrolytically unstable spirophosphoranes with five- and seven-membered rings, 2-phenyl-4,4-bis(trifluoromethyl)-4,5-dihydrospiro[[1,3,2]benzodioxaphosphepine-2,2′-phenanthro[9,10-d][1,3,2]dioxaphosphol]-5-one and 2,4′,5′-triphenyl-4,4-bis(trifluoromethyl)-4,5-dihydrospiro[[1,3,2]benzodioxaphosphepine-2,2′-[1,3,2]dioxaphosphol]-5-one.
The structure of the first of these was proved by X-ray analysis. 相似文献
13.
A series of hybrid mesoporous SBA-15 materials containing four iron(III) Schiff base complexes of the type [FeL
x
(NO3)] (x = 4–7, L = N,N′-bis(salicylidene)ethylenediamine, N,N′-bis(salicylidene)diethylenetriamine, N,N′-bis(salicylidene)o-phenylenediamine, N,N′-bis(3-nitro-salicylidene)ethylenediamine) was synthesized by a post-grafting route. The XRD, N2 adsorption/desorption and TEM measurements confirmed the structural integrity of the mesoporous hosts, and the spectroscopic
characterization techniques (FT-IR, UV–vis spectroscopy, 1H NMR) confirmed the ligands and the successful anchoring of iron(III) Schiff base complexes over the modified mesoporous
support. Quantification of the supported ligand and metal was carried out by TG/DSC and ICP-AES techniques. The catalyst FeL7-SBA resulting from N,N′-bis(3-nitro-salicylidene)ethylenediamine) ligand was considerably active for the aerobic epoxidation
of styrene, in which the highest conversion of styrene reached 83.6%, and the selectivity to styrene oxide was 83.0%. Moreover,
it was also found that the catalytic activity increases with the decrease in the electron-donating ability of the Schiff bases,
and the selectivity varies according to the types of substituents in the ligands. 相似文献
14.
Quantum chemical method PBE0/cc-pVTZ in conjunction with the polarizable continuum model (PCM) was applied to the calculation
of the equilibrium structural parameters of the benzene and naphthalene 1,2,3-oxadiazole derivatives, as well as relevant
diazocarbonyl compounds both in the free state and dissolved in dichloromethane. The calculated ionization potentials of benzo-1,2,3-oxadiazole
(9.49 eV), 6-diazocyclohexa-2,4-dien-1-one (8.16 eV) and (6-oxocyclohexa-2,4-dien-1-ylidene)carbonyl (8.34 eV) differ from
the experimental values no more than by 0.09 eV. The calculations indicate the possible existence of naphtho [2,3-d:6,7-d′]bis(1,2,3-oxadiazole) in the gas phase and in aprotic solvents. 相似文献
15.
The comparative reactivity of heterocyclic diazo compounds and the corresponding diazonium salts in C-azo coupling reactions was studied using imidazole, pyrazole, and triazole derivatives as examples.The reactivities of pyrazole- and imidazole-derived diazonium salts are much lower than those of thiadiazole- and 1,2,4-triazole-derived diazonium salts but higher than those of pyrrole and indole diazo compounds.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 348–358, February, 2005. 相似文献
16.
Eri Yoshida 《Colloid and polymer science》2010,288(8):901-905
The effects of the structure of initiators and photo-acid generators on the nitroxide-mediated photo-living radical polymerization
of methyl methacrylate were explored. The bulk polymerization was performed at room temperature using nine different initiators
in the presence of (4-tert-butylphenyl)diphenylsulfonium triflate as the photo-acid generator. 2,2′-Azobisisobutyronitrile, 2,2′-azobis(2,4-dimethylvaleronitrile),
dimethyl 2,2′-azobis(2-methylpropionate), and 2,2′-azobis(N-butyl-2-methylpropionamide) produced the polymers with a molecular weight distribution (MWD) around 1.6, while the racemic-
and meso-(2RS,2′RS)-azobis(4-methoxy-2,4-dimethylvaleronitrile) provided a 1.4 MWD. 2,2′-Azobis(2-methylbutyronitrile), 1,1′-azobis(cyclohexane-1-carbonitrile),
and 1-(cyano-1-methylethoxy)-4-methoxy-2,2,6,6-tetramethylpiperidine produced a broad MWD over 4.0. The structure of the photo-acid
generator also had an influence on the molecular weight control. The photo-acid generator of sulfonium salts supporting the
alkyl, methoxy, phenoxy, methylthio, and tert-butoxycarbonylmethoxy groups, coupled with halogens with the exception of the iodide had no effect on the MWD. On the other
hand, the salts containing the iodide, phenylthio, and naphthyl groups produced polymers with broad MWDs and with uncontrolled
high molecular weights. 相似文献
17.
V. E. Semenov O. A. Lodochnikova A. T. Gubaidullin O. N. Kataeva A. V. Chernova Y. Ya. Efremov S. V. Kharlamov Sh. K. Latypov V. S. Reznik 《Russian Chemical Bulletin》2008,57(1):124-136
Reaction of α,ω-bis(3,6-dimethyl-2,4-dioxo-1,2,3,4-tetrahydropyrimidin-1-yl)alkanes with paraformaldehyde leads to pyrimidinophanes,
which contain four 3,6-dimethyluracil fragments, connected to each other by the methylene chains. A comparative study of intra-
and intermolecular interactions of “open” and macrocyclic uracil derivatives in the crystal state and in solution was performed.
According to the NMR spectroscopy data, there is no self-association of “open” and macrocyclic compounds in chloroform solutions,
whereas the X-ray data revealed the intermolecular π-π contacts between the 3,6-dimethyluracil fragments in the crystals of
these compounds. Conclusions on the presence of intramolecular interactions in chloroform solutions of α,ω-bis(3,6-dimethyl-2,4-dioxo-1,2,3,4-tetrahydropyrimidin-1-yl)alkanes
and pyrimidinophanes were made based on the UV spectra, which were interpreted in terms of hypo- and hyperchromic effects
relatively to the model uracil derivative. These conclusions correlate with the X-ray data: there are no intramolecular π-π
contacts between the 3,6-dimethyluracil fragments both in the crystals and in solutions of “open” compounds, positions of
these fragments relatively to each other in the molecules of pyrimidinophanes are defined by the lengths of the polymethylene
bridges. The intramolecular stacking effect between the opposite uracil rings is observed for the macrocycles with trimethylene
and hexamethylene chains, whereas there is no such interactions in pyrimidinophanes with tetramethylene chains.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 119–131, January, 2008. 相似文献
18.
A. S. Gordetsov S. V. Zimina S. V. Saprykina L. B. Loginova A. V. Piskunov V. F. Ur’yash E. M. Moseeva 《Russian Journal of General Chemistry》2011,81(4):658-662
1,3,5-Tris[bis(η5-cyclopentadienyl)chlorovanadium]melamin is prepared in high yield by the reaction of N,N′-bis(trimethylsilyl)dicyandiamide with bis(η5-cyclopentadienylvanadium) dichloride in tetrahydrofuran. As side products, trimethylchlorosilane and cyclopentadiene formed.
Reaction of N,N′-bis(trimethylsilyl) dicyandiamide with benzoyl chloride results in the formation of tris(benzoyl)melamin. 相似文献
19.
Two-dimensional cyclic potential energy surface for internal rotation of vinyl and hydroxyl substituents in o-vinylphenol molecule was constructed by the B3LYP/6-311G(d) method. It was shown that o-vinylphenol molecule exists in the gas phase as a mixture of seven rotamers denoted as A (A′), B (B′), C (C′) and D. The B3LYP/cc-pVTZ calculated percentage of the rotamers A and A′ in which OH…π intramolecular interaction occurs, is at most 24%. The height of barriers t interconversions between o-vinylphenol rotamers varies from 0.1 to 5.2 kcal mol−1. According to B3LYP/cc-pVTZ calculations, the inclusion of solvent effect in the framework of the polarizable continuum model
for a solution of o-vinylphenol in CCl4 leads to a decrease in theoretical values of ν(OH) frequencies by about 4–9 cm−1 and to an increase in the percentage of the rotamers without intramolecular hydrogen bond by about 4.3% compared to the corresponding
gas-phase values. The simulated IR spectral contours of ν(OH) bands are in good agreement with experimental one
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 499–508, March, 2008. 相似文献
20.
A. F. Pozharskii N. G. Tregub N. V. Vistorobskii E. Yu. Romanova Z. A. Starikova A. I. Yanovsky 《Russian Chemical Bulletin》1999,48(7):1299-1309
The reaction of 1,8-bis(dimethylamino)naphthalene (“proton sponge”) with trifluoroacetic anhydride afforded new derivatives
of naphtho[1,8-c,d]pyran,viz., trans-) (4) andcis-1,3-dihydroxy-6,7-bis(dimethylamino)-1,3-bis(trifluoromethyl)-1H,3H-naphthol[1,8-c,d]pyran (5) and symmetrical 3,4,10,11-tetrakis(dimethylamino)-7,14-bis(trifluoromethyl)-7,14-epoxydinaphtho[1,8-a,b;1′, 8′-ef]cyclooctane (3), which belongs to a new type of double “proton sponges,” along with the expected 1,8-bis(dimethylamino)-4-trifluoroacetylnaphthalene.
The structures of compounds3 and4 were established by spectral studies and X-ray diffraction analysis. 相似文献