共查询到20条相似文献,搜索用时 9 毫秒
1.
Russian Chemical Bulletin - 相似文献
2.
G. A. Kovtun D. L. Lysenko A. S. Berenblyum I. I. Moiseev 《Russian Chemical Bulletin》1980,29(4):540-543
Conclusions An investigation of the kinetics of the initiated oxidation of p-xylene in the presence of N-phenylanthranilic acid, methyl N-phenylanthranilate, and nickel bis (N-phenylanthranilate) has shown that coordination with Ni(II) leads to a substantial enhancement of the antioxidant properties of the N-phenylanthranilate anion.For communication 2 see [1].Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 786–790, April, 1980. 相似文献
3.
4.
5.
6.
7.
8.
9.
Summary A rapid method is described for the analysis of metal thiourea complexes of Zn, Cd, Hg and Cu by adding excess of chloramine-T and determining the excess iodometrically. Colloidal suspensions of metal sulphides (Cu, Hg, Zn, Cd) have been found to undergo rapid oxidation to sulphate quantitatively in acid medium by chloramine-T.
Zusammenfassung Thioharnstoffkomplexe von Zn, Cd, Hg und Cu lassen sich durch Zugabe von überschüssigem Chloramin-T und jodometrischer Titration des Überschusses analysieren. Kolloidale Suspensionen der entsprechenden Metallsulfide werden mit Chloramin-T in saurem Medium rasch und vollständig zu Sulfat oxydiert.相似文献
10.
The reactions of N-hydroxybenzenesulfonamide (Piloty's acid, PA) with a variety of metal oxidants are reported. Either nitric oxide or nitrite is the final reaction product, along with benzenesulfinate and the reduced metal compound. The nitrogen product depends on the oxidation potential of the metal oxidant and its ability to further oxidize NO to nitrite. The observation and preliminary interpretation of unusual kinetic behavior of Piloty's acid as a reductant is also described. Analogues of PA were also prepared and found to show similar reactivity. 相似文献
11.
Dinuclear copper(II) complexes (Cu2 LnCl3), nickel(II) complexes (Ni2 LnCl3) and cobalt(II) complexes (Co2L
2
n
Cl2) from Schiff base ligands are synthesised, characterised and used as catalysts for oxidation of 3,5-DTBC to 3,5-DTBQ. (Cu2LnCl3) are found to be more efficient than the other complexes. Dinuclear iron(III) complexes of composition (Fe2L2Cl2) and ruthenium (III) complexes of composition Ru2L
2
n
Cl6(PPh3)2 and Ru2L
2
n
Cl2(PPh3)2 catalyse epoxidation of styrene and cyclohexene. Catalytic activities of ruthenium(III) complexes are much greater than those
of analogous iron(III) complexes. 相似文献
12.
13.
14.
Recently discovered catalytic reactions with ruthenium and lanthanide metal complexes have extended the scope of 1-alkynes as useful reagents. The specific formation of aryl-substituted (Z)-1,3-enzymes via the dimerization of HC(triple bond) CR(1) (R(1) = aryl) has been attained using dimeric lanthanide complexes, the catalytic activity of which appears to be unaffected by time. The dimerization of HC(triple bond) CR(2) (R(2) = t-Bu, SiMe(3)) catalyzed by Ru(cod)(cot)/PR(3) or RuH(2)(PPh(3))(3) produces a good yield of butatrienes (Z)R(2)CH=C=C=CHR(2) with a high degree of selectivity. Under certain conditions, HC(triple bond) C=SiMe(3) dimerizes to yield exclusively (Z)-M(3)Si-C(triple bond) C-CH=CH-SiMe(3). The hydration of HC(triple bond)CR(3) (R(3) = alkyl, aryl) catalyzed by RuCl(2)/PR'(3) or CpRuCl(PR"(3))(2) has realized the first example of anti-Markovnikov regioselectivity in an addition reaction of water that produces aldehydes R(3)CH(2)bond;CHO. The application of this reaction to propargylic alcohols has lead to their formal isomerization to alpha,beta-unsaturated aldehydes. In contrast, the addition of amines R(4)bond;NH(2) (R(4) = aryl) to HCtbond;CR(5) (R(5) = alkyl, aryl) conforms to Markovnikov's rule to produce ketimines R(5)bond;(C=NR(4))bond;CH(3) when catalyzed by a Ru(3)(CO)(12)/additive. Since the reaction can be performed in air without the need for any solvents, it enables the practical synthesis of aromatic ketimines, which are difficult to prepare by conventional methods. The synthesis of indoles using deactivated anilines is one practical application of this reaction. The mechanisms of some of these reactions have been analyzed in detail with the aid of theoretical calculations. 相似文献
15.
S. M. Islam Paramita Mondal Kazi Tuhina Anupam Singha Roy Dilder Hossain Sanchita Mondal 《Transition Metal Chemistry》2010,35(7):891-901
The polymer-anchored Schiff base complexes of Cu(II), Co(II), Ni(II), Mn(II) and Fe(III) were prepared by reacting polystyrene
amine with 2-pyridinecarbaldehyde followed by loading of metal atom in methanol. These complexes were characterized by using
different physico-chemical and spectroscopic methods. The catalytic activity of these polymer-supported metal catalysts was
tested for the oxidation of various olefins and alcohols. Influence of various reaction parameters, such as reaction temperature,
reaction time, oxidant, substrate-to-oxidant mole ratio and nature of solvent, was studied for the oxidation of cyclohexene
with these catalysts. Among the catalysts studied, Cu-Cat showed higher catalytic activity toward oxidation reactions than
the other catalysts. Moreover, hot filtration experiments proved that these catalysts are truly heterogeneous and can be reused
a number of times without significant loss of activity. 相似文献
16.
A. Gaudemer K. Nguyen-van-duong N. Shahkarami S.S. Achi M. Frostin-rio D. Pujol 《Tetrahedron》1985,41(19):4095-4106
Two examples of radical reactions involving cobalt complexes are described. The first one concerns the reactions of allylcobaloximes with 2-bromo 2-phenylacetonitriles leading to the corresponding monoallyl derivatives. It is shown that both the rate and regioselectivity of the reactions are affected by the nature of the substituents on the phenyl group: electron-withdrawing groups give higher rates and highly regiospecific reactions. The second type of radical reaction which finds useful synthetic applications is the oxidation of phenols by 02 catalyzed by Schiff base cobalt complexes. By choosing carefully the catalyst and the solvent, these oxidations can be highly selective, quinones being the major oxidation products in most cases. 相似文献
17.
18.
19.
Alcohol oxidation reactions catalyzed by ruthenium–carbonyl complexes of thioarylazoimidazoles
下载免费PDF全文
![点击此处可从《应用有机金属化学》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Shyamal Kumar Sarkar Mahendra Sekhar Jana Tapan Kumar Mondal Chittaranjan Sinha 《应用有机金属化学》2014,28(8):641-651
Alcohols are oxidized by N‐methylmorpholine‐N‐oxide (NMO), ButOOH and H2O2 to the corresponding aldehydes or ketones in the presence of catalyst, [RuH(CO)(PPh3)2(SRaaiNR′)]PF6 ( 2 ) and [RuCl(CO)(PPh3)(SκRaaiNR′)]PF6 ( 3 ) (SRaaiNR′ ( 1 ) = 1‐alkyl‐2‐{(o‐thioalkyl)phenylazo}imidazole, a bidentate N(imidazolyl) (N), N(azo) (N′) chelator and SκRaaiNR′ is a tridentate N(imidazolyl) (N), N(azo) (N′), Sκ‐R is tridentate chelator; R and R′ are Me and Et). The single‐crystal X‐ray structures of [RuH(CO)(PPh3)2(SMeaaiNMe)]PF6 ( 2a ) (SMeaaiNMe = 1‐methyl‐2‐{(o‐thioethyl)phenylazo}imidazole) and [RuH(CO)(PPh3)2(SEtaaiNEt)]PF6 ( 2b ) (SEtaaiNEt = 1‐ethyl‐2‐{(o‐thioethyl)phenylazo}imidazole) show bidentate N,N′ chelation, while in [RuCl(CO)(PPh3)(SκEtaaiNEt)]PF6 ( 3b ) the ligand SκEtaaiNEt serves as tridentate N,N′,S chelator. The cyclic voltammogram shows RuIII/RuII (~1.1 V) and RuIV/RuIII (~1.7 V) couples of the complexes 2 while RuIII/RuII (1.26 V) couple is observed only in 3 along with azo reductions in the potential window +2.0 to ?2.0 V. DFT computation has been used to explain the spectra and redox properties of the complexes. In the oxidation reaction NMO acts as best oxidant and [RuCl(CO)(PPh3)(SκRaaiNR′)](PF6) ( 3 ) is the best catalyst. The formation of high‐valent RuIV=O species as a catalytic intermediate is proposed for the oxidation process. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
20.
[reaction: see text]. Chiral 1,5-diaza-cis-decalins have been examined as ligands in the enantioselective oxidative biaryl coupling of substituted 2-naphthol derivatives. Under the optimal conditions employing a 1,5-diaza-cis-decalin copper(I) iodide complex with oxygen as the oxidant, rapid and highly selective couplings could be achieved (90-93% ee, 85% yield). 相似文献