Pyridine-terminated molecular rods and either (i) the cis-(dppp)(I)Pt(C÷C-triptycene-C÷C)Pt(I)(dppp) rod or (ii) the trans-(PEt3)2(I)Pt(C÷C-biphenyl-C÷C)Pt(I)(PEt3)2 rod assemble into macrocycles, characterized by NMR, ESI-IMS, and in two cases also single-crystal X-ray diffraction. The former form rectangles with bidentate phosphine-containing cis-coordinated Pt(II)-alkyne corners.
In the latter, the preference of the Pt centers for a trans configuration overrules the preference of the triple bonds for linearity and NMR shows that they have oval structures with alternating bent rod and bent trans (C÷C)Pt(PEt3)2(C÷C) components, in agreement with density functional theory calculations. Note: Sign "÷" means tripple bond.