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Updated: Aug 14, 2026

Microscopic Visualization of Porous Nanographenes Synthesized through a Combination of Solution and On-Surface Chemistry
Published on: March 4, 2021
Carbon networks based on dehydrobenzoannulenes. 5. Extension of two-dimensional conjugation in graphdiyne
Jeremiah A Marsden1, Michael M Haley
1Department of Chemistry, Materials Science Institute, University of Oregon, Eugene, Oregon 97403-1253, USA.
Abstract:
[structures: see text] 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-mediated or Pd-catalyzed oxidative homocoupling affords five new graphdiyne "oligomers" possessing two to four fused 18-membered rings. The attempted synthesis of a six-ring analogue is also reported.
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