Sterically Crowded Terphenylselenium Compounds^†

Extremely bulky terphenyltriselanes RSeSeSeR with R = 2,6-(2,4,6-Me₃C₆H₂)₂C₆H₃ and 2,6-(2,4,6-iPr₃C₆H₂)₂C₆H₃ were prepared. The chlorination with sulfuryl chloride resulted in the formation of the corresponding selenenyl chlorides RSeCl. In the case of the methyl substituted derivative, also a chlorination of the mesityl groups was observed and the derivative could be isolated. The molecular structure of the isopropyl substituted triselane [2,6-(2,4,6-iPr₃C₆H₂)₂C₆H₃Se]₂Se and that of 2,6-(2,4,6-Me₃C₆Cl₂)₂C₆H₃SeCl, have been determined by X-Ray diffraction.