The Complex Coordination Landscape of a Digold(I) U-Shaped Metalloligand

A U-shaped di-gold metallotweezer with two pyrene-imidazolylidene edges and a xanthenyl-bis-alkynyl connector was prepared. This metallotweezer acts as metalloligand in the presence of Cu+, Tl+, or Ag+, showing three clearly distinct coordination patterns depending on the cation used. The coordination to Cu+ leads to a complex in which the metalloligand is coordinated in a pincer form. The reaction with Tl+ affords a complex in which the ligand is acting as a kappa(2)-(trans)-chelate ligand. The reaction with Ag+ leads to a self-assembled structure, with two silver cations encased inside the cavity of a duplex structure formed by two self-assembled metallotweezers.