Titanium II chloride

Titanium forms dihalides TiXj, for example titanium(II) chloride, formed by heating titanium metal and the tetrachloride to about 1200 K. TiCl2 is a black solid, which disproportionates on standing to TiCl4 + Ti. Since it reduces water to hydrogen, there is no aqueous chemistry for titanium(II). A solid oxide TiO is known. 

The Stock Oxidation-Number System. Stock sought to correct many nomenclature difficulties by introducing Roman numerals in parentheses to indicate the state(s) of oxidation, eg, titanium(II) chloride for TiCl2, iron(II) oxide for FeO, titanium(III) chloride for TiCl, iron(III) oxide for Fe203, titanium(IV) chloride for TiCl, and iron(II,III) oxide for Fe O. In this system, only the termination -ate is used for anions, followed by Roman numerals in parentheses. Examples are potassium manganate(IV) for K2Mn02, potassium tetrachloroplatinate(II) for K PtCl, and sodium hexacyanoferrate(III) for Na3Fe(CN)3. Thus a set of prefixes and terminations becomes uimecessary. 

Silver difluoride, 0014 Silver fluoride, 0013 Sodium chloride, 4036 Sodium iodide, 4623 Tantalum pentachloride, 4185 Tellurium tetrabromide, 0296 Thallium, 4922 Tin(II) chloride, 4116 Tin(IV) chloride, 4174 Tin(II) fluoride, 4331 Titanium(II) chloride, 4117 Titanium dibromide, 0284 Titanium diiodide, 4630 Titanium tetrachloride, 4176 Titanium tetraiodide, 4638 Titanium trichloride, 4158... 

The reduction of TiCl4 with hexamethyldisilane does not afford titanium(II) chloride as reported by Narula and Sharma.1 Instead, the method affords an active form of titanium(III) chloride that is useful for the preparation of other titanium(III) species. 

Potassium phosphinate, 4453 Sodium disulfite, 4802 Sodium dithionite, 4801 Sodium hydride, 4438 Sodium hypoborate, 0164 Sodium phosphinate, 4467 Sodium thiosulfate, 4798 Sulfur dioxide, 4831 Tetraphosphorus hexaoxide, 4861 Tin(II) chloride, 4064 Tin(II) fluoride, 4325 Titanium trichloride, 4152 Titanium(II) chloride, 4111 Tungsten dichloride, 4113 Vanadium dichloride, 4112 Vanadium trichloride, 4153 Zinc, 4921... 

Titanium cesium alum, 6 50 Titanium (II) chloride from disproportionation of titanium (III) chloride, 6 56, 61 Titanium(III) chloride, 6 52, 57 Titanium (IV) chloride, reduction of, with hydrogen, 6 52, 57 Titanium complex compounds, cations, with acetylacetone, [Ti-(C.H. hTiCl, and [Ti(C6H7-0,),]FeCl , 2 119, 120 Titanium(IV) oxide, extraction of, from ilmenite, 5 79, 81 to titanium powder with calcium, 6 47... 

Owing to their particular interest two individual reactions will now be discussed separately. The reaction of methoxycarbonylhydrazine and 3-bromo-2,4-pentanedione affords, in addition to the expected pyrazole (608), a pyrazolium salt (609), the structure of which was established by X-ray crystallography (74TL1987). Aryldiazonium salts have been used instead of arylhydrazines in the synthesis of pyrazolines (610) and pyrazoles (611) (82JOC81). These compounds are formed by free radical decomposition of diazonium salts by titanium(ii) chloride in the presence of a,/3-ethylenic ketones. 

Trifluoroacetaldehyde (fluoral) undergoes facile highly stereoselective condensation with silyl enol ethers under titanium(II) chloride binaphthol catalysis to give 2.2... 

Titanium(II) chloride, bromide and iodide can be prepared by thermal disproportionation of TiX3 (equation 21.9) or by reaction 21.11. They are red or black solids which adopt the Cdl2 lattice (Figure 5.22). 

The synthesis described in Inorg. Synth., 1986,24,181, entitled Titanium(II) Chloride , does not produce the title compound. 

Titanium(II) chloride has been prepared by the thermal decomposition of tita-nium(III) chloride and also by the reduction of titanium(IV) chloride with metals. This compound can be obtained in relatively high purity by the direct reaction of titanium(IV) chloride and hexamethyldisilane. The procedure described below is superior to the previously reported methods because simpler equipment is used and large quantities can be processed with a resultant saving in time. 

Titanium(II) chloride is a daik reddish-brown solid. It is a strong reducing agent, and it deliquesces in air. It is sensitive to oxygen, and it is decomposed by water. Titanium(II) chloride is insoluble in diethyl ether, chloroform, carbon tetrachloride, dichloromethane, benzene, and hexane and soluble in absolute ethanol. 

Titanium (II) Chloride, Bromide and Iodide TiClg, TiBrs,... 

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