NOVEL HETEROTRINUCLEAR, PTAG2, AND HEXANUCLEAR, PT2AG4, COMPOUNDS CONTAINING BRIDGING ALKYNYL GROUPS. CRYSTAL-STRUCTURE OF [PT2AG4(C6F5)(4)(MU(3)-ETA(2)-C-CPH)(4)(PPH(3))(2)]CENTER-DOT-0.5CH(2)CL(2)

Treatment of the polymeric derivatives [{PtAg2(C6F5)(2)(C=C R)(2)}n] (R = Ph or Bu(t)) with 2 molar equivalents of neutral ligands L (Ag:L. 1:1) afforded the new more soluble trinuclear mixed-ligand complexes [PtAg2(C6F5)(2)(C=CR)(2)L(2)] 1-8 (L = PPh(3), PEt(3), CNBu(t) or C5H5N). Analogous reactions with 1 molar equivalent of L (Ag:L 2:1) produced, however, only a partial depolymerization of [{PtAg2(C6F5)(2)(C=R)(2)}(n)] to give the hexanuclear complexes [Pt2Ag4(C6F5)(4)(C=CR)(4)L(?)2,] 9-16. Compounds 9-12 have also been obtained by treatment of the binuclear derivatives [NBu(4)][Pt(C6F5)(2)(mu-C=CR)(2)AgL] with AgClO4 (1:1 molar ratio) in acetone. Similar reactions of [(PtAg2(C6F5)(2)(C=R)(2))(n)] with 1 or 0.5 equivalent of 1,2- bis(diphenylphosphino)ethane (dope) yielded insoluble complexes of composition [{PtAg2(C6F5)(2)(C=CR)(2)(dppe)}(2)] 17, 18 or [{Pt2Ag4(C6F5)(4)(C=CR)(4)(dppe)}(n)] 19, 20 which are thought to be polymeric. The crystal structure of [Pt2Ag4(C6F5)(4)(mu(3)-eta(2)-C=CPh)4(PPh3)2]. 0.5CH(2)Cl(2) 9 . 0.5CH(2)Cl(2) has been determined by X-ray diffraction methods.