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Aryl(chloromethyl)thallium chlorides, Ar(ClCH2)TlCl (Ar=C6H5, p-CH3C6H4) have been prepared by treatment of arylthallium dichlorides with diazomethane. The derived carboxylates, Ar(ClCH2)TlX, react with HgX2 to give the dicarboxylates, (ClCH2)TlX2 (X = OCOCH3, OCOC3H7-i) and with tetramethyltin to give CH3(ClCH2)TlX compounds. R(ClCH2)TIX compounds (R = CH3, C6H5, p-CH3C6H4) undergo disproportionation in methanol to R2TlX and (ClCH2)2TlX compounds.  相似文献   

3.
Dindi SN  Sarma NV 《Talanta》1985,32(12):1161-1162
A convenient method has been developed for the determination of thallium(III) by using a mercury reductor. Thallium(III) is reduced to thallium(I) in 0.5–4N hydrochloric or sulphuric acid medium and the determination is completed by oxidative titration with potassium bromate. The method is extended to analysis of thallium(III)-thallium(I) and thallium(III)-iron(III) mixtures.  相似文献   

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The reaction of TlCl3 with RLi leads to complexes of the general formula TlR2Cl (R = C6F5, p-C6F4H, m-C6F4H, 2,4,6-C6F3H2, p-C6FH4 or m-CF3C6H4). Some of these undergo oxidative addition reactions with gold(I) complexes to give polyfluorophenyl derivatives of the types AuR2ClL and Au(C6F5)R2(tht) (tht = tetrahydrothiophen), and with SnCl2 to give oily materials from which stable solids of the general formula Q[SnR2Cl3] can be isolated by addition of QCl (Q = Et4N or Ph3BzP).  相似文献   

6.
Thallium triacetate in acetic acid gave clean regeneration of both aldehydes and ketones from their toluene-p-sulphonylhydrazones. The reagent gave N-aroyl-N′-acetyl-N′-phenylhydrazines from aromatic aldehyde phenylhydrazones without prior dehydrogenation to nitrilimine intermediates.  相似文献   

7.
The preparations, stabilities and structures of the complexes R2TlX and R2 LTlX (R = C6F5, p-HC6F4, or o-HC6F4; X = Br or Cl; L = Ph3PO, 2,2′-bipyridyl (bpy) or Ph3P) have been examined or (R = C6 F5) reinvestigated. The derivatives R2TlX are monomeric in acetone, from which the complex (p-HC6F4)2 Me2COTIBr has been isolated. In this solvent, the complexes R2LTlX (L = Ph3PO, bpy, or Ph3P) undergo partial dissociation by loss of L. When L = bpy, there is also slight ionization into R2LTl+ and R2TlX?2. The acceptor properties of R2TlX compounds towards uncharged ligands decrease R = C6F5 ? p-HC6F4 > o-HC6F4 > Ph. Dimeric behaviour is observed for R2TIX compounds in benzene, whilst R2LTlX (L = Ph3PO or bpy) derivatives show slight but significant association. In the solid state, R2TlX compounds are considered to be polymeric with five coordinate thallium, and R2LTlX derivatives to be dimeric with five (L = Ph3PO) or six (L = bpy) coordinate thallium by contrast with four coordinate dimeric and four or five coordinate monomeric structures previously proposed for the respective pentafluorophenyl derivatives. Halogen bridging is unsymmetrical for R = C6F5 or p-HC6F4, but may be more symmetrical for R = o-HC6F4 when L = Ph3PO or bpy. Reported structural data for the complexes (C6F5)LTlX (L = Ph3AsO, Ph3P, Ph3As, or 1,10-phenanthroline; X = Br or Cl) and (C6F5)2TlCl?2 are reinterpreted and the proposed structures revised.  相似文献   

8.
Sharma PD  Gupta YK 《Talanta》1973,20(9):903-905
A method for estimating hydrogen peroxide by oxidation with excess of thallium(III) in the presence of iron(II) and iodometric determination of excess of thallium(III) is described. Nitrate, sulphate, manganese(II) and copper(II) have no effect. Chloride interferes.  相似文献   

9.
The second-order rate constants for mercury(II) and thallium(III)-induced aquations of trans-[Co(DH)2(R-py)Cl] (DH = dimethylglyoximate ion, R-py = pyridine, 3-picoline and 3,5-lutidine) have been measured in 40% v/v ethanol solution over a range of temperatures. The inducing effects of Hg2+ and Tl3+ are found to be quite similar and the kinetic results are discussed in terms of the formation of an activated complex CoClM (M Hg2+ or Tl3+), followed by a simple rate determining aquation in which MCl acts as the leaving group.  相似文献   

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The review is devoted to alkylation (arylation) as a widely employed derivatization procedure for the protection of OH (carboxylic acids, phosphoric acids, sulfonic acids, alcohols, polyols, phenols, enols), SH (thiols) and NH (amines, amides) groups in order to increase volatility, to improve the chromatographic properties and, if possible, mass spectral properties of derivatives. Chemical aspects of derivatization and various alkylation (arylation) reagents and reaction procedures are described. Specific mass spectral (electron ionization, chemical ionization) features of derivatives helpful in identification, structure elucidation, profiling and quantitative determination of the above-mentioned polar compounds by coupled gas chromatography or high-performance liquid chromatography are discussed. Some common analytical applications of the procedures in organic chemistry, clinical chemistry, environmental chemistry etc. are briefly summarized.  相似文献   

12.
Conclusions From the results of our calculations, we can conclude that the replacement of copper by Ni(II) atoms in Bi2Sr2CuO6 or Tl2Ba2CuO6 produces a substantial change in the character of the filled and vacant states close to EF and hence in the conduction characteristics of the original systems. On the other hand, the interaction of Ni–O and Bi(Tl)–O layers is not strong enough to produce any substantial change of charge distribution in these layers when Cu is replaced by Ni.Institute of Solid-State Chemistry, Urals Branch, Russian Academy of Sciences. Translated from Zhurnal Strukturnoi Khimii, Vol. 33., No. 4, pp. 23–27, July–August, 1992.  相似文献   

13.
We have obtained 2,7-dimethoxy-2,7-dimethyl-3,5-octadiene by the action of thallium(III) nitrate on trans-allo-ocimene.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1087–1089, May, 1990.  相似文献   

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Complexes between crown ethers having ring sizes of 15–24 atoms and 5 to 8 oxygens with HgX2 species (X = Cl, I, CN, SCN) have been prepared and studied. Interactions of the substituents X bound to mercury with groups or fragments in the crown compound are essential in determining the characteristics and stability of the complexes formed. Complexes with crowns of 18C6 ring sizes are the most favourable except for HgX2 compounds for which the size of X is larger than the macrocycle ring, as is the case for X = CF3.  相似文献   

16.
Five new compounds of ciprofloxacin (CfH = C17H18FN3O3) with cadmium(II) and mercury(II) chlorides were synthesized. The compounds were characterized by chemical analysis, powder X-ray diffraction, pH-metric titration, UV spectroscopy, and thermal analysis.  相似文献   

17.
The method of oxidation of substituted benzenes to 4,4′-biaryls by Tl(III) trifluoroacetate catalyzed by Pd(II) acetate is presented. The reactions proceed in the completely homogeneous solution of arene.  相似文献   

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A novel method is developed for the extraction separation of thallium(III) from salicylate medium with n-octylaniline dissolved in toluene as an extractant. The optimum conditions have been determined by making a critical study of weak acid concentration, extractant concentration, period of equilibration and effect of solvent on the equilibria. The thallium (III) from the pregnant organic phase is stripped with acetate buffer solution (pH 4.7) and determined complexometrically with EDTA. The method affords the sequential separation of thallium(III) from thallium(I) and also commonly associated metal ions such as Al(III), Ga(III), In(III), Fe(III), Bi(III), Sb(III) and Pb(II). It is used for analysis of synthetic mixtures of associated metal ions and alloys. The method is highly selective, simple and reproducible. The reaction takes place at room temperature and requires 15-20 min for extraction and determination of thallium(III).  相似文献   

20.
Summary Methods are described for the preparation of 1-phenylvinyl compounds of mercury and thallium from the salts of these metals and 1-phenylvinyllithium. Some chemical properties of these compounds were investigated.  相似文献   

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