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1.
The O?H bond dissociation energy (D O?H) has been determined for eight alkylseleno-substituted phenols, one alkyltelluro-substituted phenol, and one alkyltelluro-substituted pyridinol. D O?H has been estimated by the intersecting-parabolas method from kinetic data using five reference compounds: α-tocopherol (D O?H = 330.0 kJ/mol), 3,5-di-tert-butyl-4-methoxyphenol (D O?H = 347.6 kJ/mol), 4-methylphenol (D O?H = 361.6 kJ/mol), 2,6-di-tert-butyl-4-methylthiophenol (D O?H = 336.3 kJ/mol), and 2,6-di-ter-tbutyl-4-methylphenol (D O?H = 338.0 kJ/mol). The following D O?H values (kJ/mol) have been obtained: 335.9 for 2,5,7,8-tetramethyl-2-phytyl-6-hydroxy-3,4-dihydro-2H-1-benzoselenopyran, 342.6 for 2-methyl-5-hydroxy-2,3-dihydrobenzoselenophene, 333.5 for 2,4,6,7-tetramethyl-5-hydroxy-2,3-dihydrobenzoselenophene, 339.4 for 2-tert-butyl-4-methoxy-6-octylselenophenol, 357.9 for dodecyl 3-(4-hydroxyphenyl) propyl selenide, 348.5 for dodecyl 3-(3,5-dimethyl-4-hydroxyphenyl)propyl selenide, 350.9 for dodecyl 3-(3-tert-butyl-4-hydroxyphenyl)propyl selenide, 338.0 for dodecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propyl selenide, 343.0 for 2,6-di-tert-butyl-4-(tellurobutyl-4′-phenoxy)phenol, and 338.8 for 6-octyltelluro-3-pyridinol. The stabilization energies of phenoxyl radicals containing R substituents (X = O, S, Se, Te) have been compared. 相似文献
2.
Yu. N. Oludina S. V. Bukharov A. R. Burilov R. G. Tagasheva V. V. Syakaev R. Z. Musin E. F. Akhmetova G. N. Nugumanova 《Russian Chemical Bulletin》2014,63(1):115-117
Addition of isatin to the exocyclic double bond of dimethyl (3,5-di-tert-butyl-4-oxocyclohexa-2,5-dienylidene)methylphosphonate gave dimethyl (3,5-di-tert-butyl-4-hydroxyphenyl)(2,3-dioxo-2,3-dihydro-1H-indol-1-yl)methylphosphonate. Its subsequent functionalization in reactions with thiosemicarbazide and 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionohydrazide yielded isatin derivatives containing several pharmacophoric fragments. 相似文献
3.
A. P. Krysin A. M. Genaev L. M. Pokrovskii M. M. Shakirov 《Russian Journal of Organic Chemistry》2014,50(3):367-370
2,6-Di-tert-butyl-4-(2-hydroxyethyl)phenol undergoes oxidative self-coupling by the action of K3Fe(CN)6 in alkaline medium at room temperature to give 7,9-di-tert-butyl-4-(3,5-di-tert-butyl-4-hydroxyphenyl)-1-hydroxymethyl-2-oxaspiro[4.5]deca-6,9-dien-8-one. The composition of the reaction products has been determined, and the mechanism of their formation is discussed. 相似文献
4.
Joanna Kowal 《Polymer Degradation and Stability》1984,7(3):175-188
The photochemical reactions of pentaerythrityl tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] (Irganox 1010; IH) and dicumyl peroxide (DCP) initiated by long-wavelength radiation with λ>300 nm in hexane solutions and polystyrene films were studied. It was found that the rate of formation of acetophenone (APH) in the photolysis of DCP in hexane solution is lowered in the presence of IH and the rate constant for the reaction between alkoxyl radical RO? and IH is about 103 times greater than the sum of the rate constants for APH formation and hydrogen abstraction from solvent molecules by RO?.The consumption of IH was confirmed during the irradiation of PS films containing DCP and IH. The decrease in the rate of APH formation and the inhibiting effect on the photodegradation of the polymer were observed. 相似文献
5.
V. B. Vol’eva I. S. Belostotskaya N. L. Komissarova L. N. Kurkovskaya 《Russian Journal of Organic Chemistry》2008,44(6):803-806
Products of the reactions of 4- and 2-hydroxy-3,5-di-tert-butyl-benzaldehydes with malonic acid, diethyl malonate, and acetic anhydride in the presence of weak bases were isolated and identified. The reactions of 3,5-di-tert-butyl-4-hydroxybenzaldehyde with malonic acid and acetic anhydride in the presence of sodium acetate and piperidine gave 3,5-di-tert-butyl-4-hydroxycinnamic acid. The reaction of its 2-hydroxy isomer with acetic anhydride stopped at the stage of formation of the corresponding O-acetyl derivative, while in the reaction with malonic acid the corresponding substituted cinnamic acid and its lactone (coumarin derivative) were formed as intermediate products in a transformation sequence finally leading to 3-(3,5-di-tertbutyl-2-hydroxyphenyl)-3-piperidinopropionic acid and 6,8-di-tert-butyl-2-oxo-3,4-dihydro-2H-chromen-4-ylacetic acid. Analogous differences were typical of reactions of isomeric 4- and 2-hydroxy-3,5-di-tert-butylbenzaldehydes with diethyl malonate. The transformations of the 2-hydroxy isomer were accompanied by hydrolysis and formation of an adduct of intermediate coumarin derivative with diethyl malonate and piperidine. 相似文献
6.
E. M. Gibadullina T. R. Shaekhov V. V. Syakaev A. R. Burilov M. A. Pudovik 《Russian Chemical Bulletin》2012,61(7):1502-1504
A reaction of 1,3-dimethoxybenzene with dimethyl (3,5-di-tert-butyl-4-oxocyclohexa-2,5-dienylidenemethyl)phosphonate gave rise to 1,3-bis[(3,5-di-tert-butyl-4-hydroxyphenyl)-(dimethoxyphosphoryl)methyl]-4,6-dimethoxybenzene, which was oxidized to 1,3-bis[(3,5-di-tert-butyl-4-oxocyclohexa-2,5-dienylidene)(dimethoxyphosphoryl)methyl]-4,6-dimethoxy-benzene. 相似文献
7.
The rearrangement of 1-(3,5-di-tert-butyl-4-hydroxyphenyl)methyl pyridinium salts under basic conditions is described. A method for the synthesis of (3,5-di-tert-butyl-4-hydroxyphenyl)methyl-(3-pyridylalkyl)-ethers is elaborated. 相似文献
8.
Víctor M. Jiménez-Pérez Ángel Ramos-Organillo Adrián Peña-Hueso Angelina Flores-Parra 《Journal of organometallic chemistry》2007,692(25):5549-5554
The reactions of bis-(3,5-di-tert-butyl-2-phenol)oxamide (1) with Cl2SiR2 (Me or Ph) or Cl2GeR2 (Me, nBu or Ph) in THF provided binuclear pentacoordinated silicon and germanium compounds: bis-(3,5-di-tert-butyl-2-oxo-phenyl)-oxamido-bis-dimethylsilane (2), bis-(3,5-di-tert-butyl-2-oxo-phenyl)-oxamido-bis-diphenylsilane (3), bis-(3,5-di-tert-butyl-2-oxo-phenyl)-oxamido-bis-dimethylgermane (4), bis-(3,5-di-tert-butyl-2-oxo-phenyl)-oxamido-bis-di-n-butylgermane (5) and bis-(3,5-di-tert-butyl-2-oxo-phenyl)-oxamido-bis-diphenylgermane (6). The mono-nuclear tetracoordinated silicon compounds N-acetyl-bis-(3,5-di-tert-butyl-2-oxo-phenyl)-amide-bis-(dimethylsilane) (8) and N-acetyl-bis-(3,5-di-tert-butyl-2-oxo-phenyl)-amide-bis-(diphenylsilane) (9) were synthesized from N-(3,5-di-tert-butyl-2-phenol)acetamide (7) and Cl2SiR2 (R = Me and Ph). Comparison of the 29Si NMR chemical shifts of the penta- (2 and 3) and tetracoordinated (8 and 9) silicon compounds provided information about the intramolecular coordination of the carbonyl group to the silicon atom. Compounds 3 and 6 were characterized by single-crystal X-ray analyses. They have planar hexacyclic structures where the central atoms present distorted tbp geometries with one nitrogen and two carbon atoms in equatorial positions and two oxygen atoms in apical positions. 相似文献
9.
Dialkyl [(3,5-di-tert-butyl-4-oxocyclohexa-2,5-dien-1-ylidene)methyl]phosphonates reacted with phenol and benzenediols in the presence of trifluoromethanesulfonic acid to give products of electrophilic substitution in the benzene ring, the corresponding diarylmethylphosphonates or [phenylenebis(arylmethylene)]- diphosphonates. The reaction of diphenyl [(3,5-di-tert-butyl-4-oxocyclohexa-2,5-dien-1-ylidene)methyl]phosphonate with 2-methylbenzene-1,3-diol at a ratio of 1: 1 afforded 3-(3,5-di-tert-butyl-4-hydroxyphenyl)-6-hydroxy-7-methyl-2-phenoxy-2,3-dihydro-1,2λ5-benzoxaphosphol-6-one. 相似文献
10.
N. M. Storozhok N. P. Medyanik A. P. Krysin S. A. Krekov V. E. Borisenko 《Russian Journal of Organic Chemistry》2013,49(7):1031-1034
Sterically hindered phenols, 3-tert-butyl-N-(3,5-di-tert-butyl-4-hydroxyphenyl)-5-ethyl-2-hydroxybenzamide and N-[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propyl]-2-hydroxybenzamide, were synthesized as potential antioxidants, and the formation of hydrogen bonds by their molecules was shown by UV and IR spectroscopy. 相似文献
11.
The temperature dependences of the equilibrium constants of two chain reversible reactions in quinonediimine (quinonemonoimine)—2,5-dichlorohydroquinone
systems in chlorobenzene were studied. The enthalpy of equilibrium of the reversible reaction of quinonediimine with 4-hydroxydiphenylamine
was estimated from these data (ΔH = − 14.4±1.6 kJ mol−1) and a more accurate value of the N-H bond dissociation energy in the 4-anilinodiphenylaminyl radical was determined (D
NH = 278.6±3.0 kJ mol−1). A chain mechanism was proposed for the reaction between quinonediimine and 2,5-dichlorohydroquinone, and the chain length
was estimated (ν = 300 units) at room temperature. Processing of published data on the rate constant of the reaction of styrylperoxy
radicals with 2,5-dichlorohydroquinone in the framework of the intersecting parabolas method gave the O-H bond dissociation
energy in 2,5-dichlorohydroquinone: D
OH = 362.4±0.9 kJ mol−1. Taking into account these data, the O-H bond dissociation energy in the 2,5-dichlorosemiquinone radical was found: D
OH = 253.6±1.9 kJ mol−1.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1661–1666, October, 2006. 相似文献
12.
Carlos Camacho-Camacho Maria E. Castillo-Ramos Aurora Vásquez-Badillo Angelina Flores-Parra Rosalinda Contreras 《Journal of organometallic chemistry》2010,695(6):833-9863
The syntheses of [bis(3,5-di-tert-butyl-2-hydroxy-2-phenyl)amine]diphenyltin (1) and [bis(3,5-di-tert-butyl-2-hydroxy-2-phenyl)amine]dichloro-phenyl-stannate (2) by template reactions using 3,5-di-tert-butylcatechol, aqueous ammonia and SnPh2Cl2 are reported. We also report the syntheses of compounds 2, [bis(3,5-di-tert-butyl-2-hydroxy-2-phenyl)amine]trichloro-stannate (4), [bis(3,5-di-tert-butyl-2-hydroxy-2-phenyl)methylamine]chloro-methyltin (5), and [bis(3,5-di-tert-butyl-2-hydroxy-2-phenyl)-n-butylamine]n-butyl-chlorotin (6) and [bis(3,5-di-tert-butyl-2-hydroxy-2-phenyl)amine]n-butyl-dichloro-stannate (7), performed by transmetallation reactions of the octahedral zinc coordination compound Zn[3,5-di-tert-butyl-1,2-quinone-(3,5-di-tert-butyl-2-hydroxy-1-phenyl)imine]2 (3) with SnPhCl3 or SnPh2Cl2, SnCl4, SnMe2Cl2, Sn(nBu)2Cl2 and Sn(nBu)Cl3, respectively. The X-ray diffraction structures of compounds 1, 2, 4 and 6 are reported. The transmetallation reactions with Sn(alkyl)2Cl2 afforded pentacoordinated tin compounds, where an alkyl group migrated from tin to nitrogen, while similar reactions with Sn-Ph compounds did not present any phenyl group migration. 相似文献
13.
Woosik Hong Sojung Lee Haeri Lee Tae Hwan Noh Young-A Lee Ok-Sang Jung 《Transition Metal Chemistry》2012,37(6):563-567
Recrystallization of [Co(3,5-dbbq)2(L)2] (3,5-dbbq?=?3,5-di-tert-butyl-1,2-benzoquinone; L?=?bis(3-pyridyl)phenylvinylsilane) from diethyl ether at ?20?°C produces trans-[Co(3,5-dbbq)2(L)2] while the recrystallization from toluene at ?20?°C gives trans-[Co(3,5-dbbq)2(L)2]·2PhMe. The complex exists as trans-[CoIII(3,5-dbsq)(3,5-dbcat)(L)2] (3,5-dbsq?=?3,5-di-tert-butyl-1,2-semiquinonato; 3,5-dbcat?=?3,5-di-tert-butylcatecholato) in the solid state at 173?K. Differences in charge distribution between trans-[Co(3,5-dbbq)2(L)2] and trans-[Co(3,5-dbbq)2(L)2]·2PhMe have been observed based on the effective magnetic moments and IR spectra of the complexes along with their X-ray crystal structures. 相似文献
14.
Ismagilov R. K. Moskva V. V. Lebedev Yu. V. Mosunova L. Yu. 《Russian Journal of General Chemistry》2001,71(6):931-933
A method for synthesis of -(3,5-di-tert-butyl-4-hydroxyphenyl)propionic hydrazide. Certain chemical properties of the product were studied. It was found that -(3,5-di-tert-butyl-4-hydroxyphenyl) -(3,5-di-tert-butyl-4-hydroxyphenyl)hydrazide is highly susceptible to oxidation. 相似文献
15.
R. R. Starodubtseva E. M. Gibadullina N. B. Pazilova V. V. Syakaev M. A. Pudovik A. R. Burilov 《Russian Journal of General Chemistry》2017,87(9):1908-1912
Reactions of dialkyl [(3,5-di-tert-butyl-4-oxocyclohexa-2,5-dien-1-ylidene)methyl]phosphonates with butyl, benzyl and propargyl alcohols in the presence of catalytic amounts of trifluoromethanesulfonic acid resulted in the formation of nucleophilic 1,6-addition products. Azide-alkyne cycloaddition reaction of dimethyl (3,5-di-tert-butyl-4-hydroxyphenyl)(prop-2-ynyloxy)methylphosphonate with benzyl azide and 1,3-bis-(2-azidoethoxy)benzene in the presence of copper sulfate and sodium ascorbate afforded 1,2,3-triazoles with sterically hindered phenol fragments. 相似文献
16.
T. V. Bashkatova F. K. Miryasova E. N. Cherezova S. V. Bukharov 《Russian Journal of Applied Chemistry》2005,78(7):1110-1114
An efficient procedure was developed for preparing bis(3,5-di-tert-butyl-4-hydroxyphenyl) polysulfides in the presence of phenolic Mannich bases. The antioxidative activity of the resulting bis(polysulfides) in rubbers of various structures and in their vulcanizates was examined. 相似文献
17.
Chalcone, flavone, and arylideneflavanone derivatives bearing one or two 3,5-di-tert-butyl-4-hydroxyphenyl groups were synthesized from 2′,4′-dihydroxyacetophenone and 3,5-di-tert-butyl-4-hydroxybenzaldehyde. These flavonoids were converted into the corresponding malonates and then reacted with C60 to yield the title compounds. The O-H bond dissociation enthalpies (BDE) and the chain-breaking antioxidant activity of the flavonoid derivatives and the corresponding C60 conjugates were evaluated. These results are consistent with the phenolic moiety being the main responsible for the reaction with peroxyl radicals, while the C60 part of the molecule acts synergically by trapping alkyl radicals under reduced O2 partial pressure. These novel C60-flavonoid conjugates are therefore promising leads for broad-spectrum radical scavengers. 相似文献
18.
S. V. Maslennikov I. A. Aivaz'yan I. V. Spirina V. K. Cherkasov V. P. Maslennikov 《Russian Journal of General Chemistry》2005,75(10):1576-1578
The final products of oxidation of iron and nickel with 3,5-di-tert-butyl-1,2-benzoquinone in DMSO were identified, and the formal-kinetics relationships of the process were elucidated. The apparent equilibrium constants, enthalpies, and entropies of adsorption of the reactants on the metal surfaces and the rate constants and activation energies of the reactions were determined. 相似文献
19.
L. Yu. Ukhin K. Yu. Suponitskii L. V. Belousova T. N. Gribanova 《Russian Chemical Bulletin》2009,58(5):940-943
5-(3,5-Di-tert-butyl-4-hydroxyphenyl)-1,2,3,5-tetrahydrophenazine was synthesized by the reaction of 2,6-di-tert-butyl-1,4-benzoquinone-4-(o-aminophenyl)imine with cyclohexanone. The structure of the reaction product was established by X-ray diffraction. 相似文献
20.
V. P. Osipova N. A. Antonova N. T. Berberova A. I. Poddel’skii K. V. Kudryavtsev 《Russian Journal of Electrochemistry》2011,47(10):1119-1124
The method of cyclic voltammetry on a platinum electrode in acetonitrile is used to study the redox properties of a number
of novel pyrrolidine derivatives containing a sterically hindered phenol fragment. It is found that the obtained derivatives
of (3,5-di-tert-butyl-4-hydroxyphenyl)pyrrolidine-2-carboxylic acid are irreversibly oxidized in two stages with formation of a phenoxy radical.
The structural analogue containing no phenyl fragment is irreversibly oxidized under similar conditions in a single stage.
Formation of a stable phenoxy radical from synthesized (3,5-di-tert-butyl-4-hydroxyphenyl)pyrrolidines under PbO2 oxidation is confirmed by ESR spectroscopy. Application of the synthesized compounds as antioxidant agents has been suggested. 相似文献