Metal-promoted alkyne trimerisation leading to novel metallacycles. The molecular structures of [Mo{η3-C(CF3)C(CF3)C(Me)C(Ph)SPri}(CF3CCCF3)(η5-C5H5)], [WSPri{η5-C(CF3)C(CF3)C(CF3)C(CF3)C(Me)C(Ph)}(η5-C5H5)], and [W(SC6H4Me-4){η4-C(CF3)C(CF3)C(CO2Me)C(CO2Me)C(CF3)C(CF3)}(η5-C5H5)]

Abstract

Addition of alkynes to isomeric η²-C,C-vinyl [M{η³-C(CF₃)C(CF₃)SR′}(CF₃CCCF₃)(η⁵-C₅H₅)](M = Mo, W; R′= Prⁱ) and bis-alkyne complexes [MSR′(CF₃CCCF₃)₂(η⁵- C₅H₅)](M = W, R′= 4-MeC₆H₄) gives new metallacycles formed by linking of two or three alkynes; X-ray analyses reveal two modes of bonding for the tris alkyne (CR)₆ ligands.