Titanium chloride-Hydrogen peroxide

Methylenetriphenylphosphorane, 254 Titanium(IV) chloride-Lithium aluminum hydride, 310 (Z)-Alkenes By elimination reactions Dichlorobis(cyclopentadienyl)-titanium, 102 Hydrogen peroxide, 145 By hydrogenation of carbon-carbon triple bonds... 

Penuela, G.A. and D. Barcelo (2000). Comparative photodegradation study of atrazine and desethylatrazine in water samples containing titanium dioxide/hydrogen peroxide and ferric chloride/hydrogen peroxide. J.A.O.A.C. Int., 83 53-60. 

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). 

Anilines are converted into nitrosoarenes ArNO by the action of hydrogen peroxide in the presence of [Mo(0)(02)2(H20) (HMPA)]224, whereas catalysis of the reaction by titanium silicate and zeolites results in the formation of azoxybenzenes ArN (0)=NAr225. Azo compounds ArN=NAr are formed in 42-99% yields by the phase-transfer assisted potassium permanganate oxidation of primary aromatic amines in aqueous benzene containing a little tetrabutylammonium bromide226. The reaction of arylamines with chromyl chloride gives solid adducts which, on hydrolysis, yield mixtures of azo compounds, p-benzoquinone and p-benzoquinone anils 234227. 

Various substituted benzimidazoles have been synthesized in very good yields in solvent-free conditions from 1,2-diaminobenzene and aldehydes in the presence of titanium(IV) chloride as a catalyst. The method is applicable to most aromatic, unsaturated and aliphatic aldehydes and to substituted 1,2-diaminobenzenes without significant differences [14]. Several other catalysts, namely iodine [15], hydrogen peroxide [16], zirconyl(IV) chloride [17], boron trifluoride diethyl etherate [18], ytterbium perfluorooctane sulfonates [19,20], zeolite [11,21], and L-proline [22], have been effectively used for the synthesis of benzimidazole derivatives. 

Numerous other large-volume compounds can be made from ethylene and propylene by standard petrochemical methods. Ethylene can be oxidized to ethylene oxide using oxygen with a silver catalyst (12.4). Propylene can be oxidized to propylene oxide with hydrogen peroxide and titanium silicalite (see Chap. 4). Vinyl chloride (a carcinogen) is produced by adding chlorine to ethylene, followed by... 

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