J Diaryl Tellurium Amide Halides

Diaryl tellurium amide bromides were obtained in 80 to 100% yields when diaryl telluriums and A -bromosuccinimide or A -bromobenzamide were stirred in benzene.  

4-Dimethylaminophenyl 4-Methoxyphenyl Tellurium Bromide Succinimide 1.42 g (4 mmol) of 4-dimethyl-aminophenyl 4-methoxyphenyl tellurium are dissolved in 50 m/ of benzene and 0.72 g (4 mmol) of A-bromosuccinimide dissolved in 10 ml of benzene are added. The mixture is stirred for 3 h, the yellow crystalline precipitate is filtered off, washed with benzene, and dried under reduced pressure yield 2.1 g (100%) m.p. 160° 

Diaryl tellurium dichlorides and an excess of piperidine condensed in hot benzene to give diaryl tellurium chloride piperidides.  

As the bonding arrangement of cyanate and isocyanate groups to tellurium is not known (see p. 617), diorgano tellurium halide cyanates, isocyanates, thiocyanates, and isothiocyanates are treated together on the basis of formal tellurium-nitrogen bonding. 

Diaryl tellurium iodide cyanates and thiocyanates have been prepared. They are colored, crystalline solids with sharp melting points, soluble in organic solvents and stable at 20.  

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