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31.
Nadezhda Rangelova Lachezar Radev Sanchi Nenkova Isabel M. Miranda Salvado Maria H. Vas Fernandes Michael Herzog 《Central European Journal of Chemistry》2011,9(1):112-118
Methylcellulose (MC) / SiO2 organic / inorganic hybrid materials have been prepared from MC and methyltriethoxysilane or ethyltrimethoxysilane, and characterized
by XRD, FTIR and AFM. XRD showed peak shifts. FTIR shows intermolecular hydrogen bonding between MC and SiO2. AFM depicts surface roughness which depends on the silica precursor and MC content.
相似文献
32.
T. Iossifova B. Mikhova I. Kostova 《Monatshefte für Chemie / Chemical Monthly》1995,126(11):1257-1264
Summary The isolation and structure elucidation of the secoiridoid hydroxyornoside is described. The behaviour of secoiridoid dilactones on acid methanolysis is discussed.
Ein Secoiridoiddilacton aus der Rinde vonFraxinus ornus
Zusammenfassung Die Isolierung und Strukturaufklärung des Secoiridoids Hydroxyornosid wird beschrieben. Das Verhalten von Secoiridoiddilactonen bezüglich saurer Methanolyse wird diskutiert.相似文献
33.
Kalina Kostova Annalaura Lorenzi-Riatsch Yoshihiko Nakashita Manfred Hesse 《Helvetica chimica acta》1982,65(1):249-251
Synthesis of Macrocyclic Lactones by Ring Enlargement Reaction Treatment of 3-(1-nitro-2-oxocyclohexyl)propanal ( 1 ) prepared by Michael addition of 2-nitrocyclohexanon and acrylaldehyde with methyltri (2-propoxy)tita-nium yielded a mixture of 2 and 3 which was converted into 6-nitro-9-decanolide ( 4 ). 相似文献
34.
35.
Bokach NA Kukushkin VY Kelly PF Haukka M Pombeiro AJ 《Dalton transactions (Cambridge, England : 2003)》2005,(8):1354-1356
Imino(triphenyl)phosphorane, Ph3P=NH (1), reacts with nitrile complexes of Pt(IV) to generate hydrolytically sensitive [PtCl4{NH=C(R)N=PPh3}2](R=Me 2a, Et 2b, Ph 2c), and with the Pt(II) complex [PtCl2(EtCN)2] to give [PtCl2(EtCN){NH=C(Et)N=PPh3}](3) and [PtCl2{NH=C(Et)N=PPh3}2](4); X-ray crystallography performed upon (2b) and (3) confirms the presence of an imine/nitrile addition ligand bound by the terminal nitrogen. 相似文献
36.
Nikita A. Kazin Nadezhda S. Demina Roman A. Irgashev Ekaterina F. Zhilina Gennady L. Rusinov 《Tetrahedron》2019,75(33):4686-4696
The effective approaches for regioselective double formylation and acetylation of 5,12-dialkyl-6,7-diaryl-substituted 5,12-dihydroindolo[3,2-a]carbazoles by their treatment with dichloromethyl methyl ether in the presence of SnCl4 or with acetyl chloride in the presence of AlCl3 to afford the 2,9-diformyl or 2,9-diacetyl derivatives, respectively, were developed. Furthermore, new 2,9-bis(2,2-dicyanovinyl) derivatives were synthesized by the Knoevenagel condensation of diformyl-containing substrates with malononitrile, when new 2,9-bis(quinoxaline-2-yl)- and 2,9-bis(benzo[g]quinoxaline-2-yl) derivatives were formed via microwave-promoted oxidation of diacetyl-containing substrates with SeO2 to the corresponding diglyoxals, followed by the reaction of these intermediates with o-phenylendiamine or 2,3-diaminonaphthalene, respectively. The basic optical and electrochemical properties of some 5,12-dihydroindolo[3,2-a]carbazoles were investigated. 相似文献
37.
Makarycheva-Mikhailova AV Bokach NA Kukushkin VY Kelly PF Gilby LM Kuznetsov ML Holmes KE Haukka M Parr J Stonehouse JM Elsegood MR Pombeiro AJ 《Inorganic chemistry》2003,42(2):301-311
Pt(IV)-mediated addition of the sulfimide Ph2S = NH and the mixed sulfide/sulfimides o- and p-[PhS(=NH)](PhS)-C6H4 by the S=NH group to the metal-bound nitriles in the platinum(IV) complexes [PtCl4(RCN)2] proceeds smoothly at room temperature in CH2Cl2 and results in the formation of the heterodiazadiene compounds [PtCl4[NH=C(R)N=SR'Ph]2] (R' = Ph, R = Me, Et, CH2Ph, Ph; R' = o- and p-(PhS)C6H4; R = Et). While trans-[PtCl4(RCN)2] (R = Et, CH2Ph, Ph) reacting with Ph2S=NH leads exclusively to trans-[PtCl4[NH=C(R)N=SPh2]2], cis/trans-[PtCl4(MeCN)2] leads to cis/trans mixtures of [PtCl4[NH=C(Me)N=SPh2]2] and the latter have been separated by column chromatography. Theoretical calculations at both HF/HF and MP2//HF levels for the cis and trans isomers of [PtCl4[NH=C(Me)N=SMe2]2] indicate a higher stability for the latter. Compounds trans-[PtCl4[E-NH=C(R)N=SPh2]2] (R = Me, Et) and cis-[PtCl4[E-NH=C(Me)N=SPh2][Z-NH=C(Me)N=SPh2]] have been characterized by X-ray crystallography. The complexes [PtCl4[NH=C(R)N=SPh2]2] undergo hydrolysis when treated with HCl in nondried CH2Cl2 to achieve the amidines [PtCl4[NH=C(NH2)R]2] the compound with R = Et has been structurally characterized) and Ph2SO. The heterodiazadiene ligands, formed upon Pt(IV)-mediated RCN/sulfimide coupling, can be liberated from their platinum(IV) complexes [PtCl4[NH=C(R)N=SR'Ph]2] by reaction with Ph2PCH2CH2PPh2 (dppe) giving free NH=C(R)=SR'Ph and the dppe oxides, which constitutes a novel route for such rare types of heterodiazadienes whose number has also been extended. The hybrid sulfide/sulfimide species o- and p-[PhS(=NH)](PhS)C6H4 also react with the Pt(II) nitrile complex [PtCl2(MeCN)2] but the coupling--in contrast to the Pt(IV) species--gives the chelates [PtCl2[M-I=C(Me)N=S(Ph)C6H4SPh]]. The X-ray crystal structure of [PtCl2[M-I=C(Me)N=S(Ph)C6H4SPh-o]] reveals the bond parameters within the metallacycle and shows an unusual close interaction of the sulfide sulfur atom with the platinum. 相似文献
38.
L. K. Kostov W. Andrejtscheff L. G. Kostova A. Dewald G. Böhm K. O. Zell P. von Brentano H. Prade J. Döring R. Schwengner 《Zeitschrift für Physik A Hadrons and Nuclei》1990,337(4):407-412
By means of the generalized centroid-shift method, the following half-lives were determined:T 1/2(3045 keV)=3.7±0.3 ns in113Sb using the reaction104Pd(12C,p2n) as well asT 1/2 (1322.8 keV)=3.5±0.3 ns,T 1/2(2779.8 keV) =0.50±0.15ns,T 1/2(2874.9 keV)<0.2 ns andT 1/2(3072.9 keV)<0.1 ns in117Sb using the116In(α, 2n) reaction. Three-quasiparticle configurations of the type πd 5/2ν(h11/2 d 3/2) in113,117Sb are found to dominate in the wave functions of the 19/2? states at 3045 and 2780 keV in113Sb and117Sb, respectively. TheB(E2, 19/2? → 15/2?) values in113–119Sb are discussed. 相似文献
39.
Polina Angelova Kalina Kostova Karsten Hinrichs Dimiter Tsankov 《Central European Journal of Chemistry》2005,3(4):658-667
New 4-substituted benzyl esters of 16-mercaptohexadecanoic acid were prepared by developing a practicable synthetic procedure
and using readily available staring materials. The compounds synthesized have been characterized by NMR, MS, IR spectra and
elemental analysis. The mercapto derivatives are precursors for the formation of self-assembled monolayers on metal substrates.
Dedicated to Professor Dr. Manfred Hesse on the occasion of his 70
th
birthday 相似文献
40.
Alexander N. Titov Ingrid Bryntse Svetlana G. Titova Nadezhda V. Toporova 《Solid State Ionics》2001,140(3-4):293-300
The reaction between metallic Ag and PbS1.18(TiS2)n, n=1, 2, misfit layer compounds has been investigated by electrochemical technique, X-ray powder analysis and transmission electron microscopy. It was found that silver intercalation is possible only in the compound with n=2. The thermodynamic behavior and location of phase boundaries were studied in the temperature range 400–650 K. DC-conductivity and magnetic-susceptibility measurements were performed, and the data can be interpreted as an appearance of small polarons during silver insertion. 相似文献