Diorganyltellurium dichlorides

Sections 3.1-3.3 outline the principal preparative methods of diorganyl tellurides and ditellurides, organyltellurium trichlorides and diorganyltellurium dichlorides, which were the first classes of compounds investigated at the beginning of tellurium organic chemistry. 

Organyltellurium trichlorides and diorganyltellurium dichlorides are prepared starting from the electrophilic tellurium tetrachloride (or arylteUurium trichlorides) by ... 

It should also be noted that the chlorine atoms in diorganyltellurium dichlorides can be exchanged by other halogens or anionic groups. 

Employing appropriate ratios of reagents and experimental conditions, some of the reactions that convert tellurium tetrachloride into organyltellurium trichlorides (see Section 3.5.1) can be applied to the synthesis of diorganyltellurium dichlorides. 

It must be pointed out that the reaction of tellurium tetrachloride with aryl Grignard or lithium reagents is inappropriate for the preparation of diorganyltellurium dichlorides owing to the difficulty of stopping the reaction at the 1 2 stage. 

Most diorganyltellurium dihalides are stable in air. This facilitates a convenient method to purify diorganyl tellurides that are liquid at room temperature. The raw product is converted to a dichloride or dibromide by direct chlorination or bromination, and the pure dihalides are easily be reduced back to the original telluride." ... 

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