共查询到20条相似文献,搜索用时 15 毫秒
1.
T. I. Prokof’eva V. B. Vol’eva I. S. Belostotskaya N. L. Komissarova A. V. Malkova 《Russian Journal of Organic Chemistry》2011,47(7):1015-1017
Chlorination of 3,6-di-tert-butyl-1,2-benzoquinone in a two-phase catalytic system (CH2Cl2, HCl- H2O, H2O2, Bu4NCl) led to halogen addition at the C=C bond, and subsequent dehydrochlorination of the adduct gave 3,6-di-tert-butyl-4-chloro-1,2-benzoquinone. Chlorination of the latter afforded 3,6-di-tert-butyl-4,5-dichloro-1,2-benzoquinone. 相似文献
2.
M. P. Shurygina N. O. Druzhkov M. V. Arsen’ev M. P. Bubnov G. K. Fukin S. A. Chesnokov V. K. Cherkasov 《Russian Journal of Organic Chemistry》2011,47(4):486-495
Alkoxylation of 3,6-di-tert-butyl-1,2-benzoquinone with a number of diols, including propane-1,3-diol, butane-1,4-diol, di-, and triethylene glycols,
and cyclohexane-1,4-diyldimethanol, was studied. Nine new 4-alkoxy-3,6-di-tert-butyl-1,2-benzoquinones were synthesized, four of which were bis-1,2-benzoquinones with different tethers (6–13 atoms) between
the quinone fragments. Depending on the length of the chain between the hydroxy groups in glycols, bicyclic 4,5-disubstituted
3,6-di-tert-butyl-1,2-benzoquinones were formed or their stepwise alkoxylation occurred. The newly synthesized o-benzoquinone derivatives can be reduced with alkali metals to give radical anions and converted into semiquinone chelates
with manganese carbonyl. 相似文献
3.
Gabriele Kremser Oliver T. Hofmann Stefan Sax Stefan Kappaun Emil J. W. List Egbert Zojer Christian Slugovc 《Monatshefte für Chemie / Chemical Monthly》2008,139(3):223-231
Summary. 3,6-Diphenyl-9-hexyl-9H-carbazole derivatives bearing electron withdrawing groups, such as the formyl or the nitro-group in 4-positions of the phenyl
substituents, were prepared and characterized. Their photophysical properties were evaluated and compared with those of the
unsubstituted counterpart 3,6-diphenyl-9-hexyl-9H-carbazole. The electron withdrawing groups bearing compounds exhibited considerable red shifts of the absorption and the
emission maxima. While 3,6-di(4-nitrophenyl)-9-hexyl-9H-carbazole emitted in the orange region of the visible spectrum with its emission maximum peaking at 585 nm, 3,6-di(4-formylphenyl)-9-hexyl-9H-carbazole gave a pure blue emission with a luminescence quantum yield of 95% peaking at 450 nm. Observed features were explained
using quantum mechanical calculations and organic light emitting diodes using the formylphenyl substituted compound as emissive
layer were built demonstrating the practical applicability of this class of compounds. 相似文献
4.
G. K. Fukin A. V. Cherkasov M. P. Shurygina N. O. Druzhkov V. A. Kuropatov S. A. Chesnokov G. A. Abakumov 《Structural chemistry》2010,21(3):607-611
From the geometrical point of view, all observed conformations of the 3,6-di-tert-butyl-o-benzoquinone fragments are determined by the inequivalent positions of the Me groups of the tBu substitutes relative to the
carbonyl oxygen atoms. The geometrical inequivalence is believed to cause the energetic inequivalence of the Me groups. The
relevant quantum mechanical computations revealed intramolecular contacts of the C=O···H-(tBu)-type (2.37–3.83 kcal/mole)
that can be interpreted to be hydrogen bonding interactions. 相似文献
5.
A nucleophilic addition reaction of 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (OH-TEMPO) to 3,6-di-tert-butyl-o-benzoquinone was used to obtain a new sterically hindered o-benzoquinone (1) containing 2,2,6,6-tetramethylpiperidineoxyl functional group, which was characterized by IR spectroscopy, mass spectrometry, elemental analysis, and X-ray diffraction. A one-electron reduction of 1 with potassium and thallium is an efficient method for the generation of earlier unknown heterospin biradicals 5a and 5b, respectively, containing nitroxide and o-semiquinone radical centers. Analysis of the hyperfine structure of the ESR spectra of biradicals 5a and 5b in solution showed that they belong to the group of heterospin biradicals with strong (J >> a) and fast exchange interaction between the radical centers. 相似文献
6.
A. A. Volod’kin S. M. Lomakin G. E. Zaikov N. M. Evteeva 《Russian Chemical Bulletin》2009,58(5):920-925
Alkaline hydrolysis of diethyl N-acetylamino(3,5-di-tert-butyl-4-hydroxybenzyl)malonate is accompanied by decarboxylation. The efficiency of this process depends on the temperature
and ratio of the reactants. A possibility of tautomerism with migration of the proton of phenolic hydroxyl and the influence
of the structure on the antioxidation properties were considered on the basis of analysis of the IR spectral data and quantum
chemical (PM6) calculation of the structures. The energies of homolysis of the O-H bond of phenolic hydroxyl were calculated
for a series of the synthesized compounds. It is proposed to predict the antioxidation activity on the basis of these values. 相似文献
7.
V. B. Vol’eva I. S. Belostotskaya N. L. Komissarova L. N. Kurkovskaya A. P. Pleshakova T. I. Prokofeva 《Russian Journal of Organic Chemistry》2007,43(10):1488-1491
The stability of 3,5-di-tert-butylsalicylic aldehyde against oxidation is due to autoinhibiting of the chain process. However its oxidation into 3,5-di-tert-butylsalicylic acid was performed at the use of acetyl protection of the hydroxy group. In reaction of 6-bromo-2,4-di-tert-butylphenol with urotropin the formation was discovered of 3,5-di-tert-butylsalicylic acid, its nitrile and amide. 相似文献
8.
S. A. Nikolaevskii M. A. Kiskin A. A. Starikova N. N. Efimov A. A. Sidorov V. M. Novotortsev I. L. Eremenko 《Russian Chemical Bulletin》2016,65(12):2812-2819
Two novel binuclear nickel(II) complexes [Ni2(O2CR)4(2,3-lut)2] (O2CR is anion of 3,5-di(tert-butyl)benzoic acid (bzo, 1) and 4-hydroxy-3,5-di(tert-butyl)benzoic acid (hbzo, 2); 2,3-lut is 2,3-lutidine) with four carboxylate bridges were synthesized. The structure of complex 1 was determined by X-ray diffraction. Both dimers 1 and 2 were characterized by elemental analysis, IR spectroscopy, and magnetic measurements. The presence of the α-substituent in the apical lutidine ligand leads to a distortion of the geometry of the metal carboxylate core in complex 1 as a result of short steric contacts Me(Lut)…O(OOCR) (3.134(7) Å). This is apparently responsible for a considerable decrease in the exchange parameters of complexes 1 and 2 (J =–30.0 and–23.6 cm–1, respectively) as compared to known analogues. Density functional calculations of the structure and magnetic properties of 1 and 2 were carried out by the UB3LYP/6-31G(d,p) method. 相似文献
9.
V. F. Sedova V. P. Krivopalov O. P. Shkurko 《Russian Journal of Organic Chemistry》2009,45(10):1535-1540
Three-component acid-catalyzed cyclocondensation of 3,5-di-tret-butyl-4-hydroxybenzaldehyde with urea and ethyl acetoacetate or α-nitroacetophenone (Biginelli reaction) under homogeneous
conditions gave the corresponding 5-substituted 3,4-dihydropyrimidin-2(1H)-ones having in position 4 of the heteroring an aryl substituent with sterically shielded hydroxy group. The condensation catalyzed by inorganic salts
(Fe3+, Co2+, Zn2+, Li+) was successful only with ethyl acetoacetate as initial methylene-active component. Under analogous conditions, acetophenone
and 4-fluoroacetophenone gave rise to 4,6-diarylpyrimidin-2(1H)-ones which are capable of undergoing phenol-quinonemethide tautomerism. 相似文献
10.
Investigation of the catalyzed reaction of 2,6-di-tert-butylphenol with ethanol, ethylene glycol, oligomeric glycols, and paraldehyde in a strongly basic medium permitted to develop a technologically suitable procedure for manufacture of 2,6-di-tert-4-ethyl-butylphenol, used in the synthesis of Antioxidant-425. 相似文献
11.
L. P. Stepovik Yu. B. Malysheva G. K. Fukin 《Russian Journal of General Chemistry》2015,85(6):1401-1411
9-R-Anthracenes (R = Me, Ph) are effective acceptors of peroxyl and metalalkoxyl radicals in the systems tert-butylhydroperoxide-metal tert-butoxide (M = Al, V, Cr; C6H6, 20°C). Isolation of 9-R-9,10-dihydro-9,10-di-tert-butylperoxyanthracenes, 10-R-10-tert-butylperoxy-9-anthrones as major products reliably confirms the formation of tert-butylperoxy radicals and can be used for quantitative assessment of their content. 相似文献
12.
E. M. Kasymova A. R. Burilov N. A. Mukmeneva S. V. Bukharov G. N. Nugumanova M. A. Pudovik A. V. Chernova R. R. Shagidullin A. I. Konovalov 《Russian Journal of General Chemistry》2007,77(3):458-468
A method for the synthesis of new calix[4]resorcinols tetra-3,5-di-tert-butyl-4-hydroxybenzyl derivatives is developed. Their interaction with methyldichlorophosphonate, dimethyldichlorosilane in the presence of a base leads to formation of organophosphorus-organosilicon cavitands. Acetylation of hydroxybenzylated calix[4]resorcinols with acetic anhydride leads to products of either incomplete or full acetylation depending on experimental conditions. 相似文献
13.
L. Yu. Ukhin K. Yu. Suponitsky E. N. Shepelenko L. V. Belousova D. V. Alekseenko G. S. Borodkin L. N. Etmetchenko 《Russian Chemical Bulletin》2016,65(3):727-730
Heating of an equimolar mixture of 3,5-di-tert-butyl-1,2-benzoquinone with thiosalicylic acid led to 2-[(4,6-di-tert-butyl-2,3-dihydroxyphenyl)thio]benzoic acid. In the case of β-mercaptopropionic acid, 2-[(4,6-di-tert-butyl-2,3-dihydroxyphenyl)thio]propionic acid was formed, which upon reflux in Ac2O was converted to 6,8-di-tert-butyl-9-hydroxy-3,4-dihydro-2H-1,5benzoxathiepin-2-one. 相似文献
14.
R. G. Tagasheva D. R. Gataullina I. F. Zaripova S. V. Bukharov G. N. Nugumanova T. R. Deberdeev Yu. K. Voronina 《Russian Journal of General Chemistry》2017,87(1):22-28
The benzylation of benzothiazole(oxazole, imidazole)-2-thiones with 3,5-di-tert-butyl-4-hydroxybenzyl acetate involves either the sulfur or nitrogen atom depending on the reaction conditions. The S- and N-benzylation products of benzazole-2-thiones are kinetically and thermodynamically controlled products, respectively. The use of 3,5-di-tert-butyl-4-hydroxy-benzyl acetate allows sterically hindered hydroxybenzyl derivatives of benzаzole-2-thiones to be generally synthesized under milder conditions than in known methods of their synthesis. 相似文献
15.
A. P. Krysin T. B. Khlebnikova B. M. Khlebnikov L. M. Pokrovskii V. G. Vasil’ev 《Russian Journal of General Chemistry》2009,79(6):1156-1162
Vapor phase catalytic methylation with methanol of 2-tert-butylphenol at the temperature 280–300°C proceeds selectively with formation of 6-tert-butyl-2-methylphenol. Elevating reaction temperature above 300°C leads to formation of 2,6-dimethylphenol. Reaction of 2-tert-butylphenol with methanol in alkaline medium in the presence of zinc oxide is shown to lead initially to formation of a mixture of calixarenes and methylenebisphenols that at elevated temperature exert splitting leading in future to 6-tert-butyl-2,4-dimethylphenol. Obtaining it in this reaction from 2,2′-methylenebis-(6-tert-butyl-4-methylphenol) proceeds selectively. Pathways of the reductive methylation of methylenebisphenols with methanol in alkaline medium is considered. 相似文献
16.
E. V. Ilyakina O. G. Mishchenko A. V. Piskunov S. V. Maslennikov I. V. Spirina Yu. A. Kurskii A. V. Lado 《Russian Journal of General Chemistry》2009,79(4):724-727
The quantum yields of photolytic transformations of aluminum, gallium, and indium tris(3,6-di-tert-butyl-1,2-semiquinolates) in solutions of saturated hydrocarbons were determined. The final products of photodecomposition formed upon irradiation of the compounds with the light of wavelength 313 nm were identified. The kinetic scheme for decomposition of the metal o-semiquinone complexes upon irradiation is suggested. 相似文献
17.
The effect of a spatially-hindered phenol, namely sodium 1-N-acetylamino-1-carboxy-2-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, on the functionality of mitochondria of rat liver was studied. Stress impact caused a 3 to 4-fold increase in the fluorescence intensity of the products of lipid peroxidation (LPO) in the membranes of these organelles. The preparation reduced the intensity of LPO to the control level, which was conductive to maintaining high functional activity of the mitochondria. Prevention of mitochondrial dysfunction was probably associated with an increase in the resistance of animals to stress factors. 相似文献
18.
M. Vorona I. Potorochina G. Veinberg S. Belyakov I. Shestakova I. Kanepe E. Lukevics 《Chemistry of Heterocyclic Compounds》2009,45(12):1532-1538
The sulfoxide of 6Z-[2-(methoxyimino)propylidene]penicillanic acid tert-butyl ester and the sulfones of 6Z-[2-(hydroxyimino-, methoxyimino-, benzyloxyimino-, 2-bromo- and 4-bromobenzyloxyimino)-propylidene]penicillanic acid in the
syn and anti forms have been synthesized by the condensation of the sulfoxide and sulfone of 6Z-acetylmethylenepenicillanic acid tert-butyl ester with hydroxylamine, methoxyamine, benzyloxyamine, 2-bromo- and 4-bromobenzyloxyamines. The syn and anti isomers
of 3Z-(2-methoxyiminopropylidene)-4R-(benzothiazolyl-2-dithio)-2-oxoazetidinyl-1R-(2-propenyl)acetic acid tert-butyl ester were obtained by opening of the thiazolidine ring in 6Z-[2-(methoxy-imino)propylidene]-1-oxopenicillanic acid tert-butyl ester with 2-mercaptobenzothiazole. The 3Z-(2-methoxyiminopropylidene)-4R-(methylsulfonyl)-2-oxoazetidinyl-1-(2-propylidene)acetic acid tert-butyl ester was synthesized by the interaction of 1,8-diazobicyclo[5.4.0]undec-7-ene and methyl iodide with 6Z-[2-(methoxyimino)propylidene]-1,1-dioxopenicillanic acid tert-butyl ester. A dependence of the cytotoxic effect in relation to cancer and normal cells in vitro on the structure of the
substituent in position 6 and the syn and anti isomerism of the oxyimino group was established for the synthesized compounds. 相似文献
19.
E. R. Milaeva D. B. Shpakovsky I. A. Maklakova K. A. Rufanov M. E. Neganova E. F. Shevtsova A. V. Churakov V. A. Babkova D. A. Babkov V. A. Kosolapov A. A. Spasov 《Russian Chemical Bulletin》2018,67(11):2025-2034
New diphenylsulfimide derivatives containing substituents with the 2,6-di-tert-butylphenol moiety at the nitrogen atom were synthesized. Their molecular structures were established by X-ray diffraction. Antioxidant activity was experimentally evaluated by spectrophotometry based on hydrogen transfer to the stable radicals, namely, 2,2-diphenyl-1-picrylhydrazyl and the 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical cation (ABTS·+), and using in vitro lipid peroxidation in rat brain and liver homogenates. The presence of phenol and diphenylsulfimide moieties in one molecule leads to a significant enhancement of antioxidant activity. The new compounds exhibit moderate inhibitory activity against enzymes involved in carbohydrate and lipid metabolism. The evaluation of antiglycation activity showed that the new sulfimides taken at a concentration of 100 μmol L–1 have activity comparable with that of aminoguanidine. 相似文献
20.
Heterometallic complex [K3Y(Cat36)3(Dme)4] (I) or binuclear complex [Y2(Cat36)3(Dme)3] · Dme (II · Dme) is synthesized, depending on the reactant ratio, by the reaction of YCl3 with 3,6-bis(tertbutylcatecholate) potassium salt (K2Cat36) in 1,2-dimethoxyethane (Dme). Both complexes are characterized by single-crystal X-ray diffraction analysis (CIF files CCDC nos. 1527929 (I) and 1527930 (II)) and 1H and 13C NMR spectroscopy. 相似文献