Cleavage of Tellurium-Carbon Bonds of Hexavalent Organotellurium Compounds by Potassium Graphite

The potassium ion intercalated in graphite results in unique reactivity of Ar5Te−K+C8 (1), formed by cleavage of one of the Te−C(Ar) bonds of Ar6Te (see scheme) by KC8. Thus, 1 reacted quantitatively with CH3I to give Ar5TeCH3, which was not obtainable from Ar5Te−Li+. The Te−CH3 bond of Ar5TeCH3 is cleaved in preference to the Te−C(Ar) bonds, and formation of Ar4Te(CD3)2 suggests the intermediacy of the hypervalent dianion Ar4Te2−.