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A variety of hexaorganotellurium compounds, Ar6−n(CH3)nTe [Ar=4-CF3C6H4, n=0 (1 a), n=1 (3 a), n=2 (trans-4 a and cis-4 a), n=3 (mer-5 a), n=4 (trans-6 a); Ph, n=0 (1 b), n=1 (3 b), n=2 (trans-4 b); 4-CH3C6H4, n=0 (1 c), n=1 (3 c), n=2 (trans-4 c), n=4 (trans-6 c); 4-BrC6H4, n=0 (1 d)] and Ar5(R)Te [Ar=4-CF3C6H4, R=4-CH3OC6H4 (8); Ar=4-CF3C6H4, R=vinyl (9), Ar=Ph, R=vinyl (10), Ar=4-CF3C6H4, R=PhSCH2 (11), Ar=Ph, R=PhSCH2 (12), Ar=4-CF3C6H4, R=nBu (13)] and pentaorganotellurium halides, Ar5TeX [Ar=4-CF3C6H4, X=Cl (2 a-Cl), X=Br (2 a-Br); Ar=Ph, X=Cl (2 b-Cl), X=Br (2 b-Br); Ar=4-CH3C6H4, X=Cl (2 c-Cl), X=Br (2 c-Br); Ar=4-BrC6H4, X=Br (2 d-Br)] and (4-CF3C6H4)4(CH3)TeX [X=Cl (trans-7 a-Cl) and X=Br (trans-7 a-Br)] were synthesized by the following methods: 1) one-pot synthesis of 1 a, 2) the reaction of SO2Cl2 or Br2 with Ar5Te−Li+ generated from TeCl4 or TeBr4 with five equivalents of ArLi, 3) reductive cleavage of Ar6−m(CH3)mTe (m=0 or 2) with KC8 followed by treatment with CH3I, 4) valence expansion reaction from low-valent tellurium compounds by treatment with KC8 followed by reaction with CH3I, 5) nucleophilic substitution of Ar6−y−z(CH3)zTeXy−z (X=Cl, Br, OTf; z=0, 1; y=1, 2) with organolithium reagents. The scope and limitations and some details for each method are discussed and electrophilic halogenation of the hexaorganotellurium compounds is also described.

The reaction of pentaphenyltellurium chloride 2 with silver perchlorate afforded the pentaphenyltelluronium salt, Ph5Te+ClO, (1b), and treatment of 2 with silver triflate and sodium tetrakis{3,5-bis(trifluoromethyl)phenyl}borate provided Ph5Te+[3,5-(CF3)2C6H3]4B− (1c), which were isolated as stable yellow solids. X-ray crystallographic analyses of the hypervalent telluronium salts revealed square-pyramidal geometry around the tellurium, which are rare examples for penta-substituted main group element compounds. © 2001 John Wiley & Sons, Inc. Heteroatom Chem 12:380–384, 2001

Te(C6H4-4-CF3)61a was obtained by the unique one-pot reaction of LiC6H4-4-CF3 with TeCl4. The Te atom resides in the highest oxidation state (TeVI) having six C Te bonds in 1a. Compound 1a is extremely thermally stable and not light sensitive unlike tetraorganotellurium compounds. The X-ray crystallographic analysis of 1a revealed a rare example of approximately Th molecular symmetry.

A novel family of organochalcogens, Ph5TeX (X = Cl, Br), was readily obtained by the halogenation of Ph5TeLi, which was prepared by reaction of 5 equiv of PhLi with 1 equiv of TeCl4 or TeBr4; Ph5Te...

Te(C6H4-4-CF3)61a was obtained by the unique one-pot reaction of LiC6H4-4-CF3 with TeCl4. The Te atom resides in the highest oxidation state (TeVI) having six C Te bonds in 1a. Compound 1a is extremely thermally stable and not light sensitive unlike tetraorganotellurium compounds. The X-ray crystallographic analysis of 1a revealed a rare example of approximately Th molecular symmetry.