Niobium IV chloride

Niobium(IV) chloride, NbCl4(THF)2. This reagent (1) can be obtained1 by reduction of NbCl5 with aluminum powder in CH,CN followed by solvation with THF m.p. 110° dec., yield 50%. 

Die Reaktion von Nitrilen verschiedenen Typus mit Tributylstannan in Thiolan in Ge-genwart eines Niobium(IV)-chlorid-Tetrahydrofuran-Komplexes fiihrt zu reduktiver C —C-Verkniipfung unter Bildung von vicinalen Diaminen, z.B.2 ... 

Niobium(IV)-chlorid-Tetrahydrofuran-Komplex um und erhalt nach Hydrolyse der inter-mediaren N-Niobium-Derivate die gewiinschten Diamine1. 

Nitrile lassen sich mittels Niobium(IV)-chlorid-Bis-tetrahydrofuran/Tributylstannan in Thiolan reduktiv zu vicinalen Diaminen kuppeln1. Die Ausbeuten sind dabei im allge-meinen etwas geringer als bei der vorgenannten, von N-Silyl-iminen ausgehenden Me-thode. 

Extension of Method—TungstenfJV) Chloride and Niobium(IV) Chloride... 

The method has also been examined for the production of other nonvolatile compounds. In these cases, the purification process involves subliming excess starting materials away from the product. For example, greater than 95 % yields of tungsten(IV) chloride from tungsten(VI) chloride and 85% yields of niobium-(IV) chloride from niobium(V) chloride can be obtained by using a 500-watt light bulb at 150°C. and a reaction period of 3 days. 

In an inert-atmosphere dry-box, 2.36 g (0.01 mole) of niobium tetrachloride is suspended in 25 ml of acetonitrile in a 100-ml round-bottomed flask equipped with a magnetic stirring bar. Niobium(IV) chloride is conveniently prepared by reduction of niobium(V) chloride with aluminum metal. " This mixture is stirred for ca. 1 hr and then 5.84 g (0.06 mole) of potassium thiocyanate dissolved in 25 ml of acetonitrile is added. Stirring is continued for 4 hr to allow for complete reaction. The red solution is filtered through a medium-porosity sintered-glass frit, separating the insoluble potassium chloride from the soluble K2[Nb(NCS)e]. The KCl precipitate is washed with three 5-ml portions pf... 

Niobium(iv) chloride reacts with a variety of / -keto-enol molecules to give 8-coordinate, tetrakischelate molecules 17 these have one unpaired electron and are not isostructural with analogous Zr and Hf compounds. Tantalum(iv) chloride reacts by abstracting oxygen, and analogous complexes are not obtained. 

Niobium(IV) chloride NbCI, 13669-70-6 234.718 viol-bik monoci cry dec 800 276 subi 3.2 reac H O... 

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