Shape-Persistent 2D Oligomers

Significance

The authors report the first example of a shape-persistent 2D oligomer that is well ­defined and characterizable. Their unique synthetic strategy allows introduction of functionality at the rim as well as above and below the molecular plane and can be obtained in different sizes. Although some defined rigid 2D structures have already been known, an approach towards objects in a size range of the inorganic counterparts can be rarely found. The key step in the macrocycle formation was performed by an intramolecular dimerization of acetylene units under pseudo-high-dilution conditions by addition of a dilute solution of 1 in pyridine over four days in the presence of CuCl/CuCl₂.