SYNTHESIS AND CRYSTAL STRUCTURE OF TRIPHENYLTELLURIUM(IV)ETHYLXANTHATE: AN EXAMPLE OF ENHANCEMENT OF THE COORDINATION NUMBER OF TELLURIUM THROUGH LONG Te‐S BONDS

Abstract

Triphenyltellurium(IV)ethybtanthate, [Ph₃Te(S₂COEt)], has been synthesized and its single crystal structure has been determined by X-ray diffraction. It has a dimeric structure in which each xanthate ligand forms an asymmetric chelate ring where one sulfur atom is involved in bridging the two tellurium atoms. The coordination environment around each tellurium atom is a very distorted octahedron constituted by two facial sets, one of three carbon atoms and the other of three sulfur atoms. The enhancement of coordination number of each tellurium from a value of five to six occurs through the formation of a long bridging Te‐S bond (3.284(3), 3.703(3) Å). The four v(Te‐S) bands in the IR spectra of [Ph₃Te(S₂COEt)] occurring at 287, 280, 198 and 190 cm⁻¹ are probably due to these tellurium-sulfur interactions.

Key Words:

• Triphenyltellurium(IV)ethylxanthate
• crystal structure
• xanthate
• tellurium.