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101.
102.
Andre Maisonnat Philippe Kalck Rene Poilblanc 《Journal of organometallic chemistry》1974,73(2):C36-C38
In the course of the study of the reactivity of the dinuclear complexes [RhCl(CO)(C2H2)]2 and [RhSR(CO)2]2 towards nucleophiles, two series of dinuclear pentacoordinated rhodium(I) complexes, [RhCl(CO)(C2H4)(amine)]2 and [RhSR(CO)2PR3]2, have been isolated. 相似文献
103.
Michele Daney Brigitte Labrande Rene Lapouyade Henri Bouas-Laurent 《Journal of organometallic chemistry》1978,159(4):385-399
The structure of 9-trimethylsilyl-9,10-dihydroanthracene (Me3SiDHA) has been studied by NMR; the coupling constants of the three 9,10 protons do not change at between 25 and 90°C (ABM spectrum; JAB }- 18.2; JAM ? 1.2; JBM ? 0.3 Hz in toluene-d8), indicating that the Me3Si group prefers the quasi axial position. In the presence of BuLi in THF, Me3SiDHA reacts with Me3SiCl to yield three new products: 9,9-bis(trimethylsilyl)-9,10-dihydroanthracene (IId) (major), (9,10-dihydroanthracen-9-yl)dimethylsilyl(trimethylsilyl)methane (V) and (9-trimethylsilyl-9,10-dihydroanthracen-9-yl)dimethylsilyl(trimethylsilyl)-methane (VI) together with the known 9,10-bis(trimethylsilyl)-9,10-dihydroanthracene (cis and trans). The carbanion of Me3SiDHA can also be alkylated (alkyl Me, Et, i-Pr) to the new 9,9-disubstituted derivatives: 9-Me3Si-9-alkyl-DHA.The formation of the carbanion of Me3SiDHA has been investigated and reveals a competition in the abstraction by the base of H9 and H10; the latter is less crowded but the 9-carbanion is stabilized by the vicinity of the silicon atom. The carbanion obtained from Me3SiDHA reacts exclusively at C(9) with D2O. A study of the alkylation of 9-trimethylsilyl-9-deuterio-9,10-dihydroanthracene shows that the generation of the 10-carbanion is followed by a 1,4 hydrogen rearrangement which yields the 9-carbanion. The mechanism is discussed and the roles of Me3Si and t-Bu are compared in the DHA series. 相似文献
104.
Nicole Brasseur Rene Ouellet Karina Lewis William R. Potter Johan E. van Lier 《Photochemistry and photobiology》1995,62(6):1058-1065
The photodynamic therapy (PDT) activity of the bis(dimethylthexylsiloxy)silicon 2,3-na-phthalocyanine (SiNc 8 ) was evaluated against the EMT-6 tumor implanted intradermally in BALB/c mice. The SiNc 8 was formulated in aqueous emulsions based on Cremophor EL or Solutol HS 15. The formulation was shown to affect plasma clearance and overall pharmacokinetics. Compared to Cremophor, Solutol promoted rapid plasma clearance and high liver retention of the dye, combined with a slight increase of dye tumor concentrations. The PDT action spectrum for tumor response of SiNc 8 in Cremophor (190 mW cm2, 200 J cm2, 24 h postinjection [p.i.] of 1 (jimol kg1) showed a maximum at 780 nm, which corresponds to the absorption maximum of the monomelic dye as well as the in vivo maximum change in the “diffuse optical density” produced by the dye. The extent of tumor necrosis increased with augmented dye and light doses. Regardless of the formulation, at 1 h p.i. of 0.1 μmol kg?! SiNc 8 , PDT efficiency (190 mW cm'2, 400 J cm2) was high but accompanied by severe damage to normal tissues, at 24 h PDT resulted in complete tumor regression in 80% of the animals without adverse effects to adjacent tissues, while at 72 h p.i. PDT induced no tumor response with Cremophor and only a partial response with Solutol. At the latter time point, plasma dye clearance was nearly complete while tumor tissue levels remained high, suggesting that tumor response correlates with plasma rather than tumor dye levels. Skin sensitivity of SKhl mice to solar-simulated radiation was lower with SiNc 8 as compared to Photofrin®. Our data suggest the potential of SiNc 8 as a far-red absorbing photosensitizer in clinical PDT. 相似文献
105.
[reaction: see text]. A simple and mild TEMPO-CuCl catalyzed aerobic oxidation of primary and secondary alcohols to the corresponding aldehydes and ketones in ionic liquid [bmim][PF6] with no trace of overoxidation to carboxylic acids has been developed. The product can be isolated by a simple extraction with organic solvent, and the ionic liquid can be recycled or reused. 相似文献
106.
Herein, we report on our studies on the reaction of organoselenium compounds with triazoles under thermal conditions using simple Rh(ii) catalysts. These reactions do not provide the product of classic rearrangement reactions. Instead two different cascade reactions were uncovered. While allyl selenides react in a cascade of sigmatropic rearrangement and selenium-mediated radical cyclization reaction to give dihydropyrroles, cinnamyl selenides undergo a double rearrangement reaction cascade involving a final aza-Cope reaction to give the product of 1,3-difunctionalization. Theoretical and experimental studies were conducted to provide an understanding of the reaction mechanism of these cascade reactions. The former provide an important insight into fundamental question on the nature of the ylide intermediate in rearrangement reactions and reveal that organoselenium compounds take up multiple roles in rearrangement reactions and mediate a free ylide reaction mechanism.Herein, we report on our studies on the reaction of organoselenium compounds with triazoles under thermal conditions using simple Rh(ii) catalysts. 相似文献
107.
Vojtech Adam Pavel Hanustiak Sona Krizkova Miroslava Beklova Josef Zehnalek Libuse Trnkova Ales Horna Bernd Sures Rene Kizek 《Electroanalysis》2007,19(18):1909-1914
In this paper we proposed a palladium(II) biosensor. The biosensor is based on determining of interactions between palladium(II) and metallothionein modified hanging mercury drop electrode by means of differential pulse voltammetry. We studied influence of two supporting electrolytes (potassium or sodium chloride) on the signals of the biosensor. Based on the results obtained we found potassium chloride (0.05 M) as the most suitable supporting electrolyte to determine palladium(II). The detection limit of the biosensor for palladium ions was evaluated as 100 nM with RSD about 10%. Moreover, we utilized the biosensor for measurement of the target molecule in the presence of human blood serum and human urine. 相似文献
108.
109.
Carlos L. P. Carone Rubens Bisatto Griselda B. Galland Rene Rojas Guillermo Bazan 《Journal of polymer science. Part A, Polymer chemistry》2008,46(1):54-59
An α‐iminocarboxamide nickel complex was activated by trimethylaluminum (TMA) and used in the polymerization of ethylene and its copolymerization with 10‐undecen‐1‐ol. The best activity was observed upon activation with 9 equiv of TMA at a temperature of 26 °C. NMR spectroscopic studies did not show 10‐undecen‐1‐ol incorporation. However, FTIR analyses suggest the incorporation of a very small amount of comonomer, which affects the glass transition temperature, the degree of branching, and the mechanical properties of the materials. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 54–59, 2008 相似文献
110.
Smith JM Lachicotte RJ Holland PL 《Journal of the American Chemical Society》2003,125(51):15752-15753
Reaction of the three-coordinate complex LFeCl (L = bulky beta-diketiminate) with KBEt3H gives a dark red iron(II) hydride complex. The complex is a dimer in the solid state, but spectroscopy and kinetics suggest that an orange three-coordinate monomer is in equilibrium with the dimer in solution. The double bond of azobenzene is completely cleaved by heating with the hydride complex, and a hydrazido intermediate can be isolated. 相似文献