Molybdenum trihalides

Molybdenum hexafluoride. 3,1412 Molybdenum-iron-sulfur complexes, 4,241 Molybdenum oxide amino acid formation prebiotic systems, 6, 872 Molybdenum storage protein microorganisms, 6, 681 Molybdenum telluride, 3, 1431 Molybdenum tetraalkoxides physical properties, 2, 347 Molybdenum tribromide, 3,1330 Molybdenum trichloride, 3,1330 Molybdenum trifluoride, 3, 1330 Molybdenum trihalides, 3, 1330 bond lengths, 3, 1330 magnetic moments, 3,1330 preparation, 3,1330 properties, 3, 1330 structure, 3,1330 Molybdenum triiodide, 3,1330 Molybdenum trioxide complexes, 3, 1379 Molybdenum triselenide, 3, 143)... 

Molybdenum supplements, 17 40 Molybdenum trihalides, 17 26 Molybdenum trioxide, 17 9, 20 Molybdenum wire, manufacture of, 17 9 Molybdic oxide, 17 9... 

Undoubtedly, the best method for the production of pure anhydrous lanthanide trihalides involves direct reaction of the elements. However, suitable reaction vessels, of molybdenum, tungsten, or tantalum, have to be employed silica containers result in oxohalides (27). Trichlorides have been produced by reacting metal with chlorine (28), methyl chloride (28), or hydrogen chloride (28-31). Of the tribromides, only that of scandium has been prepared by direct reaction with bromine (32). The triiodides have been prepared by reacting the metal with iodine (27, 29, 31, 33-41) or with ammonium iodide (42). 

The substitution reactions on action of phosphorus trihalids or acylhalids on molybdenum (II) alkoxides have also been investigated in detail ... 

Ziegler-Natta Catalysts (Heterogeneous). These systems consist of a combination of a transition metal compound from groups IV to VIII and an organometallic compound of a group I—III metal.23 The transition metal compound is called the catalyst and the organometallic compound the cocatalyst. Typically the catalyst is a halide or oxyhalide of titanium, chromium, vanadium, zirconium, or molybdenum. The cocatalyst is often an alkyl, aryl, or halide of aluminum, lithium, zinc, tin, cadmium, magnesium, or beryllium.24 One of the most important catalyst systems is the titanium trihalides or tetra-halides combined with a trialkylaluminum compound. 

In the fused state, the straightforward method is to allow either the lanthanide metal or the alkaline earth metal to react with a melt of the alkaline earth halide and the lanthanide trihalide. This approach yields the desired divalent ions if inert containers are used. Satisfactory reduction has been obtained in molybdenum, tungsten, and tantalum. The... 

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