Titanium tetrafluoride

Tin reacts completely with fluorine above 190°C to form tin tetrafluoride [7783-62-2] SnF. Titanium reacts appreciably above 150°C at a rate dependent on the size of the particles the conversion to titanium tetrafluoride [7783-63-3] TiF, is complete above 200°C. Fluorine reacts with zirconium metal above 190°C. However, the formation of a coating of zirconium tetrafluoride [7783-64 ] ZrF, prevents complete conversion, the reaction reaching... 

Titanium tetrafluoride [7783-63-3] TiF, has potential for use in dental hygiene products. It is used in infrared transmitting haflde glass. 

Titanium tetrafluoride may be prepared by the action of elemental fluorine on titanium metal at 250°C (5) or on Ti02 at 350°C. The most economical and convenient method is the action of Hquid anhydrous HF on commercially available titanium tetrachloride in Teflon or Kynar containers. Polyethylene reacts with TiCl and turns dark upon prolonged exposure. The excess of HF used is boiled off to remove residual chloride present in the intermediates. 

The most promising appHcation of titanium tetrafluoride is for use in topical appHcations for prevention of dental caries (7—13). It is being evaluated and compared to NaF, MFP, and SnF2 used in these appHcations. The other use is in mixed optical haHde glass (14—16), and in the preparation of fluorotitanates (17—19). 

Titanium Trifluoride. The trifluoride (121) is a blue crystalline soHd, density 2980 kg/m, ia which the titanium atoms are six-coordinate at the center of a slightly distorted octahedron, where the mean Ti—F distance is 197 pm. Titanium trifluoride [13470-08-1] is stable ia air at room temperature but decomposes to titanium dioxide when heated to 100°C. It is insoluble ia water, dilute acid, and alkaUes but decomposes ia hot concentrated acids. The compound sublimes under vacuum at ca 900°C but disproportionates to titanium and titanium tetrafluoride [7783-63-3] at higher temperatures. 

Titanium Tetrafluoride. Titanium tetrafluoride [7783-63-3] is a white hygroscopic soHd, density 2798 kg/m, that sublimes at 284°C. The properties suggest that it is a fluorine-bridged polymer in which the titanium is six-coordinate. The preferred method of preparation is by direct fluorination of titanium sponge at 200°C in a flow system. At this temperature, the product is sufficiently volatile that it does not protect the unreacted sponge and the reaction proceeds to completion. The reaction of titanium tetrachloride with cooled, anhydrous, Hquid hydrogen fluoride may be used if pure hydrogen fluoride is available. 

A patent (122) for the production of pigment-grade titanium dioxide describes preparation of titanium tetrafluoride by the reaction of SiF and ilmenite. 

Titanium tetrafluoride reacts with Ti(OR)4 in a manner similar to TiCl especially if pyridine is present. 

Titanium reacts with all halogens at high temperatures. It reacts with fluorine at 150°C forming titanium tetrafluoride, TiF4. Reaction with chlorine occurs at 300°C giving tetrachloride TiCR. Bromine and iodine combine with the metal at 360°C forming their tetrahahdes. 

Pentacoordinate chiral hydrosilanes were generated in situ from triethoxysilane and a C2-symmetric ligand derived from bisproline (22). In the presence of a catalytic amount of the ligand, prochiral ketones were reduced in moderate yield with moderate enantioselectivity (up to 64% ee). Use of titanium tetrafluoride, a Lewis acid, along with complexes of (22) led to higher enantioselectivity and improved yields.364... 

There is a lack of structural information for the remaining tetrafluorides. In the first transition series titanium tetrafluoride is very... 

The polyformals which were obtained in this manner from the alicyclic diols were highly colored, and their inherent viscosities were below 0.4 (determined using 60/40 phenol-tetrachloroethane mixture as solvent). Catalysts which were used were ferric chloride, methanedisulfonic acid, camphorsulfonic acid, antimony trifluoride, and titanium tetrafluoride. Polymers were not obtained with the latter two. 

Shrestha BM, Mundorff SA and Bibby BG (1972) Enamd dissolution I. Effects of various agents and titanium tetrafluoride. J Dent Res 51 1561-1566. 

Wei Shy, Soboroff DM and Wefel JS (1976) Effects of titanium tetrafluoride on human enamel. J Dent Res 55 426 -431. 

TIF4[g] TITANIUM TETRAFLUORIDE (GAS) 1683 UB12 URANIUM DODECABORIDE 1729... 

A safer alternative to toxic stannane derivatives is the use of nontoxic and inexpensive allyltrimethylsilane. The problem of the weaker nucleophilicity of this reagent was solved by an efficient in situ activation of the carbonyl mediated by the inexpensive titanium tetrafluoride as Lewis acid (Scheme 7.34). ° Good results in terms of yield and enantioselectivity were described using 10% of the complex preformed from titanium tetrafluoride... 

Brownstein, S. 1980. Complex fluoroanions in solution. Complexes of silicon, germanium and titanium tetrafluorides with simple anions. Canadian J. Chemistry 5% . 1407-11. 

Many of the promoters used are either toxic or expensive, or both. Catalytic activation possesses a distinct advantage then, in that only a relatively small amount of the promoter is required. Various catalytic promoters have been reported. These include boron trifluoride etherate [30], titanium tetrafluoride [31] and even various Brpnsted acids [21]. 

A well-formulated product will ensure a level of fluoride in the saliva above 0.02 ppm for several hours [18]. Fluoride ions are present in toothpaste formulations largely in the form of stannous fluoride (Snp2), sodium monofluorophosphate (NajPOsF), and sodium fluoride (NaF). But we can also find in the literature potassium fluoride, lithium fluoride, aluminum fluoride, zinc fluoride, acidic phosphate fluoride, ammonium fluoride, titanium tetrafluoride, and amine fluoride. 

Silicon tetrafluoride s. under AlClg Titanium tetrafluoride s. under SF SiF, TiF ... 

Sulfur tetrafliioride/titanium tetrafluoride 1,1,1-Trifluorides from carboxylic acids s. 16, 606 SFJTiF COOH CFg... 

A mixture of B-trichloro-N-tri-n-propylborazine and titanium tetrafluoride heated cautiously to start the reaction which is then controlled by cooling or maintained by gentle warming until the entire mixture has a moist appearance B-trifluoro-N-tri-ii-propylborazine. Y 95%. F. e. s. K. Niedenzu, H. Beyer, and H. Jenne, B. 96, 2649 (1963). 

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