Formation of Planar Chiral Platinum Triangles via Pillar[5]arene for Circularly Polarized Luminescence

Chiral metal–organic complexes hold great promise as new functional materials that exhibit unique stereochemical and optical properties. Here, we report the formation of optically pure pillar[5]­arene-based platinum chiral metallacycles. By coordination with 60° and 90° Pt­(II) acceptors, planar chiral platinum triangles were self-assembled efficiently and characterized by multiple spectroscopic techniques. Optical studies indicated that these metallacycles had chiral properties: pS enantiomers showed a negative Cotton effect, and pR enantiomers exhibited a positive Cotton effect. In addition, these metallacycles also exhibited circularly polarized luminescence.