Tropylium perchlorate

Performic acid Silver perchlorate Tropylium perchlorate... 

The reaction of 2,4,6-trihalophenols with tropylium perchlorates in the presence of triethylamine gives phenolate dye (Scheme 10) followed by acetylation to give dye 76 from which the leuco compounds 77 can be prepared103 by catalytic reduction using Pd-C/H2. 

The structure of tropyl azide, which is synthesized by the action of azide ion on tropylium perchlorate , may be represented as the covalent azidocycloheptatriene (161), the non-benzenoid aromatic tropylium salt with azide as the counter-ion (162), or an equilibrium mixture of the two. Spectroscopic studies by Wulfman and colleagues indicate that in non-polar solvents such as carbon... 

In an improved process for the synthesis of tropilidene (5) by E. Muller, a solution of diazomethane in benzene is added gradually to refluxing benzene containing cuprous bromide as catalyst. Benzene is used in large excess, and the product is isolated most easily by filtering the solution from the catalyst and adding it to a solution of phosphorus pentachloride in carbon tetrachloride. The tropylium chloride which separates is dissolved in water and treated with perchloric acid to afford tropylium perchlorate in 85% yield. The success of the method is attributed to formation of the intermediate (3), a deactivated electrophilic carbon metal complex. Tropilidene... 

Cyclopropene underwent cycloaddition to tropylium perchlorate in aqueous dioxane at 20 °C to give an oily alcohol oxidation with chromic acid gave predominantly the ketone 4 derived from endo addition. ... 

Tri(4-tolyl)ammonium perchlorate, 3824 Triuranium octaoxide, 4871 Trivinylantimony, 2405 TrivinyIbismuth, 2391 Tropylium perchlorate, 2742 Tungsten, 4925... 

Carbonium ions are Lewis acids, but most are too reactive to permit study of their effectiveness as catalysts for olefin isomerizations. An exception is tro pylium ion. The kinetics of tropylium perchlorate-catalyzed isomerization of 7-methyl-l,3,5-cycloheptatriene to a mixture of 1-, 2-, and 3-methyl-1,3,5-cycloheptatrienes in acetonitrile solutions at 25°C were studied. Isomerization rate was proportional to 7-methyltropylidene concentration and tropylium-ion concentration. The reaction probably involves reversible hydride transfer tropylium ion and the methyltropylidenes. 

Tropone allowed to react with phosgene or oxalyl chloride, the resulting chloro-tropylium chloride dissolved in acetic anhydride, ice-cooled, and treated dropwise with the equimolar amount of 70%-HC104 dilorotropylium perchlorate (Y 80-90%) stirred 2 hrs. at room temp, with excess dry isopropanol -> isopropoxy-tropylium perchlorate (Y 81%). F. e., also substitution with mercaptans and amines, s. E. Haug and B. Fohlisch, Z. Naturf. 24b, 1353 (1969). 

An index for predicting the reaction course of intramolecular photochemical cyclization of cycloheptatrienes and tropones, based upon the LCAO coefficients at the reaction sites of the HOMO S and LUMO s of the excited states, has been developed. The n.m.r. spectrum of the 8,9-benzobicyclo[5,2,0]nonatetraenyl anion (118) shows the presence of bond fixation and a preference for the dimethyl-enecyclobutene form. ° The rates of one-electron reduction of cyclopropyl-substituted tropylium perchlorates by chromous ion are consistent with the cyclopropyl group preferring a bisected conformation. ... 

Diacetylmethyl-tropylium salts (10) have been made and studied, treatment with triethylamine causing cyclization [to (11)] reminiscent of the behaviour of phenolic tropylium salts. Acetonyl-tropylium perchlorate has been depro-tonated to a substance (12), which underwent cycloaddition with acetylenic esters... 

Fig. 8. Height of adsorption prewave on polarogram of tropylium perchlorate (supporting electrolyte 0.1 N chloric acid) (1) and solubility of di-tropyl in aqueous ethanol (2) at 20 C [44].

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