FORMATION OF ARYNEZIRCONOCENES FROM SUBSTITUTED DIARYL BIS(TERT-BUTYLCYCLOPENTADIENYL)ZIRCONIUM - APPLICATION TO THE SYNTHESIS OF NEW FUNCTIONALIZED ORTHO-DICHALCOGENOBENZENE COMPOUNDS

The para-substituted diphenylzirconocenes [(t-BuCp)2Zr(p-C6H4R)2; R = Br, NMe2] (A) were easily obtained from the reaction of the appropriate organolithium reagent with bis(t-butylcyclopentadienyl)zirconium dichloride. Elimination of bromobenzene or N,N-dimethylaminobenzene from A by slight heating led to arynezirconocenes into which were inserted two equivalents of elementary chalcogens. As a result dichalcogenated zirconacycles [(t-BuCp)2ZrY2C6H3R; Y = S, Se] (B) were obtained. Complexes B constitute useful potential synthons in organic synthesis and a large family of new functionalized dichalcogenated benzenic compounds was prepared by reacting electrophiles. The structure of complexes B as well as related benzenic derivatives has been confirmed by micro-analysis, H-1 NMR and mass spectrometry.