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111.
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Nataliya Yu. Strutynska Vyacheslav N. Baumer Igor V. Zatovsky Artem A. Babaryk Nikolay S. Slobodyanik 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(4):i39-i41
The complex phosphate tricaesium calcium iron bis(diphosphate), Cs3CaFe(P2O7)2, has been prepared by the flux method. Isolated [FeO5] and [CaO6] polyhedra are linked by two types of P2O7 groups into a three‐dimensional framework. The latter is penetrated by hexagonal channels along the a axis where three Cs atoms are located. Calculations of caesium Voronoi–Dirichlet polyhedra give coordination schemes for the three Cs atoms as [8 + 3], [9 + 1] and [9 + 4]. The structure includes features of both two‐ and three‐dimensional frameworks of caesium double pyrophosphates. 相似文献
114.
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
115.
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
116.
117.
Artem A. Zemtsov Marina I. Struchkova Vladimir A. Tartakovsky 《Journal of fluorine chemistry》2011,132(6):378-381
The interaction of 2-nitrocinnamates with silicon reagents Me3SiRf (Rf = CF3, C2F5, and C6F5) promoted either by sodium acetate in DMF or by tetrabutylammonium acetate in dichloromethane has been described. The reactions proceed as conjugate addition of fluorinated carbanion at the CC bond and afford 3-aryl-2-nitrobutanoates bearing a fluorinated substituent in good yields as diastereomeric mixtures in ratio from 1:1 to 1.6:1. 相似文献
118.
Acylation through Ketene Intermediates 总被引:1,自引:0,他引:1
Carboxylic acids possessing a strong electron-withdrawing group in the alpha-position undergo facile dehydration upon reaction with carbodiimides to form the corresponding substituted ketenes that can react in situ with alcohols providing esters in a high yield. The ketene formed by the treatment of ethyl 2-methylmalonate with DCC was trapped in situ by a [4+2] cycloaddition with a second DCC molecule. The chemoselectivity of the acylation through the ketene intermediates was found to be substantially different from that of conventional acylation reagents showing a very low sensitivity toward the steric bulk of alcohols. A comparison of the sensitivity of the acylation to the steric bulk of alcohols supports the presence of a pseudopericyclic pathway for the nucleophilic addition of alcohols to ketenes derived from ethyl malonic and diethylphosphonoacetic acid. 相似文献
119.
Kissel’ A. A. Lyubov D. M. Cherkasov A. V. Trifonov A. A. 《Russian Journal of Coordination Chemistry》2019,45(4):266-272
Russian Journal of Coordination Chemistry - On treatment of the yttrium bis(alkyl) complex [ArNC(=CH2)C(Me)=NAr]Y(CH2SiMe3)2(THF) (I, Ar = C6H3-iso-Pr2-2.6) containing an amide-imine ligand, with... 相似文献
120.
Tolpygin A. O. Cherkasov A. V. Fukin G. K. Trifonov A. A. 《Russian Journal of Coordination Chemistry》2019,45(4):288-294
Russian Journal of Coordination Chemistry - The reaction of 2,6-diisopropylaniline with m-phenylenedibenzimidoyl chloride 1,3-C6H4{N=C(Ph)Cl}2 in the presence of triethylamine in a toluene solution... 相似文献