Boron tellurium oxides

When the reaction was carried out in chloroform in the presence of ethyl carbamate with boron trifluoride-etherate as catalyst, /J-ethoxycarbonylaminoalkyl phenyl tellurium oxides were formed. These tellurium oxides were not purified but reduced with hydrazine to the corresponding tellurium compounds. ... 

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. 

The pure compound crjrstallises in needles, M.pt. 288 C., which are soluble in benzene, xylene, or chloroform, less soluble in alcohol, and insoluble in water. Mercury di-p-tolyl gives the same type of products as mercury diphenyl (see table, p. 74) when it reacts with halogens, halogen acids, mercuric chloride, boron or arsenic trichlorides, phosphorus trichloride, silicon tetrachloride, nitrogen tri- and tetr-oxides, sulphur, selenium, and tellurium. ... 

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