Titanium III Compounds

Preparation of Titanium(IIl) Sulphate Solution- Pour 7-10 ml of an acidihed titanyl sulphate solution into a test tube, add 3-5 ml of a 10% sulphuric acid solution, and put in two or three small pieces of zinc. How does the colour of the solution change Write the equation of the reaction. 

Studying the Properties of Titanium(in) Compounds. Pour 2 ml of the titanium(III) sulphate solution prepared in the preceding experiment into each of two test tubes. Let one tube stand in the air. What is observed Add several drops of a potassium permanganate solution to the other tube. What happens Write the equations of the reactions. 

Pour the remaining titanium(III) sulphate solution off the zinc into a third test tube and rapidly add to it a 10% sodium hydroxide solution. See how titanium(III) hydroxide reacts with the oxygen of the air, and also with 10% acid and alkali solutions. Write the equations of the reactions. What properties do titanium(III) compounds exhibit  

Why do titanium(III) salts hydrolyze to a smaller extent than titanium(IV) salts Using the crystal field theory, explain why titanium(III) compounds are coloured, while titanium(IV) ones are oolourless. 

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The discussion above might have pertained for example, to the energies and electronic spectra of titanium(iii) compounds. The same ideas can be applied with just one modification to the i/-electron properties of copper(ii) complexes and other... 

Breslow and Newburg (57) pointed out that polymerization takes place mainly when the titanocene exists as titanium(IV). According to Henrici-Olive and Olive (58), the rate of polymerization decreases with increasing intensity of the electron spin resonance signals of the developing titanium(III) compound. 

Titanium(III) compounds can be produced by reduction of compounds containing titanium in the +4 state. In aqueous solution Ti3+ exists as the purple Ti(H20)63+ ion, which is slowly oxidized to titanium(IV) by air. Titanium ) is not stable in aqueous solution but does exist in the solid state in compounds such as TiO and dihalides of the type TiX2. 

The majority of titanium (III) compounds are rather easily oxidized and must be handled in an inert atmosphere. However, the titanium(III) urea derivative is relatively stable and can be kept in dry air for several weeks without suffering any apparent oxidation. In moist air or aqueous solution oxidation is much more rapid. Hexaureatita-nium(III) perchlorate has been prepared by the reduction of titanium (IV) compounds and subsequent reaction of the titanium (III) ion with urea in the presence of sodium perchlorate. The following procedure is a modification of this method. 

It can be mentioned that a titanium(III) compound was recently found [21] to be an efficient electron donor for the Fe4S4 cluster in Fe protein of nitrogenase and can therefore be used in N2 enzymatic reduction. 

This is a striking improvement over other fluorinating reagents. In addition, this elegant method of fluorination can be applied to complexes exhibiting an 0X0 or imido function and to titanium(III) compounds. 

As depicted in Scheme 6.10 the titanium(III) compound VIII was prepared in situ and half an equivalent di-tm-butylperoxide was added. Heating the reaction mixture up fast until reflux affords a deep red suspension, which was taken to dryness. The residue was extracted with dichloromethane and was filtered. Layering the solution with n-hexane afforded deep red crystals of... 

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