Thallium-molybdenum compounds

The (IsQ-coordinated species [Mo(CO)3(py)3] prepared from [Mo(CO)6] and pyridine is useful for the synthesis of various jr-allyl molybdenum compounds (68JOM(13)Pl, 970M5365). The 3-allyl complexes [( 3-allyl)Mo(CO)2Br(py)2] form [( 3-allyl)Mo(CO)2(S,S)(py)] with the anionic S,S-donors, dithiocarbamates and xanthates of sodium and potassium, M (S,S) (81JOM(218)185). [( 3-C3H5)Mo(CO)2(py)2Br] (68JO M(14)375) with thallium hexafluorophosphate in acetonitrile gives... 

The chief use of antimony and its chlorides is for accelerating the chlorination of organic compounds. Chlorination is also accelerated by the chlorides of iron, aluminium, molybdenum or thallium, and the metals themselves may be used. 

The purple molybdenum bronzes have the general formula AMoeOn, where A = Li, Na, K or Tl. The potassium and thallium members have trigonal structures while the Li and Na compounds show different types of distortions, which result in monoclinic symmetry. The ideal value of A in this structure should be 1.0 however, it seems to be closer to 0.9 for all members except Tl. Only for the Na compound has a slight stoichiometry range (0.84 < x < 0.96) been observed. The origin of this behavior is not clear although it may be electronic in nature. 

Cr(II) may be used to carry out all the reactions of Ti(III), but usually under milder conditions. Applications of Cr(II) as a reductant have been reviewed. The applications include Sn(IV) chloride in the presence of catalysts such as Sb(V) or Bi(III), Sb(V) in 20% HCl at elevated temperatures, Cu(II), silver, gold, mercury, bismuth, iron, cobalt, molybdenum, tungsten, uranium, dichromate, vanadate, titanium, thallium, hydrogen peroxide, oxygen in water and gases, as well as organic compounds such as azo, nitro, and nitroso compounds and quinones. Excess Cr(II) in sulfuric acid solution reduces nitrate to ammonium ion. The reduction is catalyzed by Ti(IV), which is rapidly reduced to Ti(III). 

See also Aluminum Antimony Arsenic Barium Beryllium Bismuth Boron Cadmium Cesium Chromium Cobalt Copper Gallium Iron Lead Lithium Manganese Mercury Metallothionein Molybdenum Nickel and Nickel Compounds Platinum Potassium Selenium Silver Sodium Tellurium Thallium Tin Titanium Tungsten Uranium Vanadium Zinc. 

Considering the denticity of ligand products typically assembled, the most often encountered are tetradentate macrocycles, followed by hexadentate species. Potentially tridentate macrocyclic products are described for nickel(II), copper(II), bor-on(III) and molybdenum(O) silver(I) and mercury(II) promote assembling penta-dentate and hexadentate macrocycles thallium(I), strontium(II), lanthanum(III) and the lanthanides(IIl) from Ce to Gd (Pm was not studied bccau.sc of its radioactivity) hexadentate products and the metal ions from Tb to Lu promote the formation of tetra- and hexa-dentate macrocyclic ligand products. Variable denticity of synthesised systems is conunon to most first-row transition elements as well as to alkaline metal ions which serve mainly to form crown ethers and related compounds. 

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