Tellurium Dioximates

Diaryl Tellurium Dioximates Diorgano Tellurium Dicyanates... 

Diaryl tellurium dichlorides and the sodium salts of ketoximes reacted in benzene at 20° to give diaryl tellurium dioximates. These oximates are white, crystalline solids. 

Diaza-l,6-dioxa-6fl-tellurapentalenes 97 were obtained in 4—60% yields by oxidation of 1,3-diketone dioximes with tellurium dioxide (79BSF199). 

On treatment with concentrated hydrochloric acid and aluminum amalgam, l-telluracyclohexane-3,5-diones decompose with elimination of tellurium. Their chemical behavior is determined by the presence of the dicoordinate tellurium center and two carbonyl groups in their molecules. As cyclic diketones, compounds 12 readily form oximes and dioximes under treatment with hydroxylamine. The former reaction is preferably carried out in dilute acetic acid solution, whereas the latter is carried out in basic... 

Selenium dioxide and tellurium dioxide react with 1,3-diketone dioximes unsubstituted at position 2, to give compounds (198) and (199), respectively. Selenium monochloride and tellurium tetrachloride give identical results (Scheme 88) (49JCS274, 79BSF(2)199). 

Dioximes or bis(arylhydrazones) of /3-diketones, react with chlorides or oxides of sulfur, selenium or tellurium, to produce various polyheterapentalenes, as indicated in Scheme 5. 

Phenyl tellurium trichloride and triarylarsane dioximates reacted with replacement of one chloride for a dioximate group1. 

Phenyl tellurium trichloride (2 mol) and triarylarsane dioximates reacted in refluxing benzene to produce phenyl tellurium dichloride oximates5. 

Bis[benzoylmethyl] tellurium diiodide in absolute ethanol was mixed with hydroxylamine hydrochloride. A solution of sodium acetate in ethanol was dropped to the mixture. Heating this mixture for 10 hours produced the dioxime of bis[benzoylmethyl tellurium diiodide3. 

Dimethyl-7>IV-[1,2,5]oxatellurazoIo[2,3-6][l,2,5]oxatellurazole 6.5 g (50 mmol) of 2,4-pentanedione dioxime and 8.8 g (55 mmol) of tellurium dioxide are added to a mixture of 180 ml of xylene and 20 ml of pcntanol and the resultant mixture is heated under reflux for 24 h. The solvents are then evaporated under vacuum, the residue is dissolved in the minimum amount of benzene, and this solution is chromatographed on a column of silica gel with benzene as the mobile phase. The orange colored band is collected, the solvent is evaporated, and the residue is recrystallized from cyclohexane yield 2.5 g (20%) m.p. 145°. 

The dioxime of 5,5-dimethyl-l,3-cyclohexanedione and tellurium tetrachloride reacted in chloroform to produce 6,7- (2,2-dime ihylpropano )-Telw-[l, 2,5 oxatellurazolo[2,3-b ... 

Oxidizing agents indude lead dioxide, manganese dioxide, tellurium dioxide, zinc peroxide, caldum peroxide, zinc chromate, alkali chromates, cumene hydroperoxide and organic tin compounds [18,31], Activators like NH3, diphenylguanidine, quinone dioxime, DMF, water and 2,4,6-trisdimethy-laminomethylphenol are also sometimes used [31],... 

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