Carbon networks based on dehydrobenzoannulenes. 5. Extension of two-dimensional conjugation in graphdiyne nanoarchitectures

The synthesis and optical properties of a series of multinanometer-sized substructures of the phenyl-diacetylene carbon allotrope, graphdiyne, are described. These molecules are among the largest and most complex annulenic systems yet prepared, with extension of linear conjugation in two-dimensions to over twice that of any previously reported planar macrocycle. The graphdiyne substructures are constructed through convergent syntheses, taking advantage of three key intermediates and silane-protected phenylacetylenes. Intramolecular macrocyclization of alpha,omega-polyyne precursors via Cu-niediated or Pd-catalyzed oxidative homocoupling affords five new graphdiyne oligomers possessing two to flour fused 1.8-membered rings. The attempted synthesis of a six-ring analogue is also reported.