Triphenylchloromethane triphenylmethyl

The Triphenylmethyl Ion.—A solution of triphenylchloromethane in a dissociating solvent conducts the electric current (Walden). Since, on electrolysis, triphenylmethyl is liberated at the cathode, it follows... 

The triphenylmethyl ion is also, very probably, present in the orange-yellow products of the salt and complex salt type which are produced from triphenylcarbinol with concentrated sulphuric acid and from triphenylchloromethane with metallic chlorides (ZnCl2, A1C13, SnCl4, SbCl6). 

In the same way the above-mentioned complex salts of triphenylchloromethane are readily decomposed by water. In both cases a hydrolysis occurs which causes the triphenylmethyl ion to lose its charge, and the carbinol to be re-formed. 

Dirarylmethyl and triarylmethyl ions (trityl ions) are even more stable than the /er/-butyl ion which is impressively demonstrated by the commercial availability of solid [Ph3C] [BF4] and similar salts. Triphenylchloromethane dissociates in polar, inert solvents such as SO2, and therefore, it is not surprising that El spectra of triphenylmethyl compounds almost exclusively exhibit this ion together with some of its fragments, whereas the molecular ion peak is usually absent. Field desorption allows to circumvent this problem (Chap. 8.5). 

However, when m-DNB was added to a solution of triphenylchloromethane and potassium tcrt-butylate in 2,2-dimethoxypropane, the yield of the substitution product and dimer of the triphenylmethyl radical markedly increased and decreased, respectively (Simig and Lempert 1979). Therefore, the main pathway of the reaction does not involve the ion-radical step. These authors suggested an alternative pathway, which is conformed by a thorough structural analysis of the secondary products formed along with tert-butyl ester of triphenylcarbinole (Huszthy et al. 1982a, 1982b) (Scheme 4.21). 

A seemingly minor technical problem, the ability of triphenylmethyl to pick up virtually any solvent as solvent of crystallization, occupied Gomberg for some time and led him into consideration of then fashionable structures involving tetravalent oxygen, which were later abandoned. Another sidetrack, more serious in view of the absence of a useful theory, was caused by experiments based on the known fact that triphenylchloromethane showed salt-like conductivity in solution in liquid SO2 It was thus definitively established that there are carbonium salts in the true sense of the definition applied to salts. When triphenylmethyl was dissolved in liquid SO2, it was found that it too conducted the electric current quite well. " How should one explain this strange phenomenon, a hydrocarbon behaving like an electrolyte ... 

Triphenylcarbinol, 811, 813, 814, 816 Triphenylchloromethane, 811, 815, 952 Triphenylguanidine, 643 Triphenylmethane, 509, 515 Triphenylmethyl sodium, 477,479 Triple point, 37, 38 Tri-n-propyl carbinol. 259 Trityl chloride, 815... 

If pure triphenylchloromethane and freshly prepared sodium amalgam are used, the yield of triphenylmethyl sodium should be almost quantitative and the concentration is usually 0.15 mol per litre (1). The reagent should be used as soon as possible after its preparation. 

It was nearly ten years before Gomberg s proposal was generally accepted. It now seems clear that what happens is the following the metal abstracts a chlorine atom from triphenylchloromethane to form the free radical triphenyl-methyl two of these radicals then combine to form a dimeric hydrocarbon. But the carbon-carbon bond in the dimer is a very weak one, and even at room temperature can break to regenerate the radicals. Thus an equilibrium exists between the free radicals and the hydrocarbon. Although this equilibrium tends to favor the hydrocarbon, any solution of the dimer contains an appreciable concentration of free triphenylmethyl radicals. The fraction of material existing as free radicals is about 2% in a 1 A/ solution, 10% in a 0.01 M solution, and nearly 100 in very dilute solutions. We could quite correctly label a bottle containing a dilute solution of this substance as triphenylmethyl radicals. ... 

A specific reagent for the primary hydroxyl group determination is triphenylchloromethane [22], which has a very reactive chlorine atom and a bulky substituent (triphenylmethyl). Due to the high steric hindrance of triphenylchloromethane, a selective reaction with primary hydroxyl groups takes place. Unfortunately, the precision is not very high because the secondary hydroxyl groups react only to a very small extent (8-10%). In order to make it a more precise method, it is necessary that before the determination, a calibration curve should be done and the real primary hydroxyl content is corrected by the decrease in the quantity of secondary hydroxyl reacted. 

Triphenylchloromethane, (CeH5)3001, which is also called triphenylmethyl chloride, is a compound of importance on account of the fact that it yields a remarkable hydrocarbon, triphenylmethyl (439), when treated with zinc. The substance itself possesses unusual properties. It is best prepared by treating benzene with carbon tetrachloride in the presence of aluminium chloride. The halogen atom in triphenylchloromethane is very reactive. It is replaced by hydroxyl when the latter is allowed to stand with water at room-temperature —... 

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