From Organo Tellurium Halides or Dithiocarbamates

Alkyl tellurium halides, RTeX, in general, have no importance as starting materials for the preparation of alkyl tellurium trihalides. The alkyl tellurium halides are synthesized from dialkyl ditellurium compounds and elemental halogens. When alkyl tellurium trihalides are the desired products, there is no reason to prepare the monohalides first. However, when the tellurium monohalide is formed during the introduction of tellurium into an organic molecule, the reaction of this primary product with halogens is the method of choice for the preparation of the tellurium trihalides. This situation is realized for 3-oxo-l-propen-1-yl tellurium halides  

3- Diphenyl-3-oxo-l-propen-l-yl Tellurium Trichloride A solution of 1.00 g (2.7 mmol) 1,3-diphenyl-3-oxo-l-propcn-l-yl tellurium chloride in 10 m/dichloromethane is chilled to 0°. Chlorine is bubbled through the solution until the initial gold color of the solution fades to pale yellow. The mixture is eoncentrated and the residue recrystallized from acetonitrile yield 66% m.p. 166-168 (bright yellow needles). 

Similarly prepared were the following 3-oxo-I-propen-l-yl-tellurium trichlorides  

3- Diphenyl-3-oxo-l-propen-l-yl Tellurium Tribromide A solution of 0.42 g (2,4 mmol) of 1,3-diphenyl-3-oxo-1-propen-l-yl tellurium bromide in 10 w/ dichloromethane is chilled to 0°. A solution of 0.19 g (1.2 mmol) of bromine in 2.5 ml dichloromethane is added. The pale-yellow solution is concentrated and the residue recrystallized from acetonitrile yield 89% m.p. 162° (orange crystals). 

Irgolic Organic Tellurium Compounds with one Te,C Bond 

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