Benzenetellurinyl trifluoroacetate

The reaction of allyltrimethylsilane with benzenetellurinyl trifluoroacetate, followed by a primary or secondary amine (octylamine, aniline, piperidine, etc.) and boron trifluoride... 

Mixed anhydrides such as benzenetellurinyl acetate (PhTe(O)OAc), benzenetellurinyl trifluoroacetate (PhTe(0)OCOCF3) and benzenetellurinyl trifluoromethanesulphonate (PhTe(0)0S02CF3), prepared by reacting benzenetellurinic anhydride with acetic anhydride, trifluoroacetic anhydride and trifluoromethane-sulphonic anhydride, respectively, have been recognized as valuable oxidizing reagents, in some cases superior to the parent benzenetellurinic anhydrides. ... 

Water tor hydrolysis is furnished by the reaction forming benzenetellurinyl trifluoroacetate formation (see above). 

Benzenetellurinyl trifluoroacetate, QFFTeOCOCF, (1), is prepared by reaction of benzenetellurinic anhydride with trifluoroacetic anhydride.1... 

Benzenetellurinyl trifluoroacetate and allyltrimethylsilanes reacted in 1,2-dichloroethane at 20° in the presence of boron trifluoride diethyl etherate to produce allyl phenyl telluroxides. The unstable telluroxides were not isolated but detected in solution by NMR spectroscopy. They were reduced to allyl phenyl tellurium derivatives with hydrazine hydrate. 

When the O-ethylcarbamido group is present in an olefin at a position suitable for ring closure, the reaction with benzenetellurinyl trifluoroacetate produces a benzenetellurinyl-substituted, nitrogen-containing heterocyclic compound1. 

Better yields were obtained when benzenetellurinyl trifluoroacetate was used in place of the acetate1. 

Reactions between benzenetellurinyl trifluoroacetate and cycloalkenes, terminal olefins, or internal olefins in acetonitrile with boron trifluoride-etherate as catalyst produced fi-acetamidoalkyl or -cycloalkyl phenyl tellurium oxides. These oxides were reduced with hydrazine hydrate in ethanol2. 

Benzenetellurinyl trifluoroacetate converts olefins in the presence of acetonitrile, propionit-rile, or benzonitrile, in a reaction catalyzed by boron trifluoride-diethyl etherate to 2-acylamino-1-ethyl phenyl tellurium oxides. The mixture was then heated at 75° for 3 h to effect elimination of the phenyltelluro group and cyclization to the dihydrooxazole5. 

Benzenetellurinyl trifluoroacetate and 1-trimethylsily 1-2-propenes reacted at 20° in 1,2-dichloroethane in the presence of boron trifluoride etherate to give allyl phenyl tellurium oxides in almost quantiative yields. These compounds were not isolated but reduced to allyl phenyl telluriums with hydrazine hydrate or converted to allylamines2. 

Olefins react with benzenetellurinyl trifluoroacetate in acetonitrile in the presense of boron trifluoride etherate to give 2-acetaminoalkyl phenyl tellurium oxides that are converted, upon treatment with triethylamine in tetrahydrofuran at 30° for 4 h, to 4,5-dihydro-l,3-oxazoles4. These highly regio- and stereoselective reactions allow the one-pot, high-yield conversion of olefins to 1,3-oxazoles. Ethyl cyanide and phenyl cyanide can be used instead of acetonitrile. 

When the addition of benzenetellurinyl trifluoroacetate to an olefin is carried out in 1,2-dichloroethane in the presence of ethoxycarbonylcyanamide and the resultant addition product heated at 75° for 3 h, ethoxycarbonylamino-substituted 4,5-dihydro-l,3-oxazolcs were obtained1. 

Allylsilanes react with benzenetellurinyl trifluoroacetate in 1,2-dichloroethane to give allyl phenyl tellurium oxides. Addition of amines to the reaction mixtures results in the formation of allylamines1. 

Only a few examples of arenetellurinyl carboxylates, the mixed anhydrides of tellurinic acids and carboxylic acids, are known. These eompounds were prepared by refluxing mixtures of arenetellurinic acid anhydrides with acetic or trifluoroacetic acid or their anhydrides in chloroform . Acetonitrile and 1,2-dichloroethane were also used as solvents. Benzenetellurinyl trifluoroacetate is described as a very hygroscopic, intractable oil. The arenetellurinyl acetates are solids with melting points of approximately 150°. 

When the reactions between benzenetellurinyl trifluoroacetate and the olefins were carried out with acetonitrile as the solvent in the presence of some trifluoroacetic acid, 2-acetylaminoalkyl phenyl tellurium oxides were formed. ... 

Allylamines are obtained by sequential treatment of allylsilanes with benzenetellurinyl trifluoroacetate in the presence of BFj EtjO and then with an alkylamine. ... 

BF3-etherate followed by allyltrimethylsilane in 1,2-dichloroethane added to a soln. of benzenetellurinyl trifluoroacetate (generated from benzenetellurinic anhydride and trifluoroacetic anhydride) in the same solvent, the mixture stirred at room temp, for 1 h, treated with p-chloroaniline, then stirring continued at 65° for 6 h N-allyl-p-... 

Benzenetellurinyl trifluoroacetate s. under BF Lithium perchlorate s. under Me SiN Tetra-n-butylammonium bromide s. under NaH... 

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