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Synthesis and assembly of extended quintulene.

ABSTRACT: Quintulene, a non-graphitic cycloarene with fivefold symmetry, has remained synthetically elusive due to its high molecular strain originating from its curved structure. Here we report the construction of extended quintulene, which was unambiguously characterized by mass and NMR spectroscopy. The extended quintulene represents a naturally curved nanocarbon based on its conical molecular geometry. It undergoes dimerization in solution via ?-? stacking to form a metastable, but isolable bilayer complex. Thermodynamic and kinetic characterization reveals the dimerization process as entropy-driven and following second-order kinetics with a high activation energy. These findings provide a deeper understanding of the assembly of conical nanocarbons. Comparison of optical properties of monomer and dimer points toward a H-type interlayer coupling in the dimer.

SUBMITTER: Hou H

PROVIDER: S-EPMC7414228 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature

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Synthesis and assembly of extended quintulene.

Hou Hao H Zhao Xin-Jing XJ Tang Chun C Ju Yang-Yang YY Deng Ze-Ying ZY Wang Xin-Rong XR Feng Liu-Bin LB Lin Dong-Hai DH Hou Xu X Narita Akimitsu A Müllen Klaus K Tan Yuan-Zhi YZ

Nature communications 20200807 1

Quintulene, a non-graphitic cycloarene with fivefold symmetry, has remained synthetically elusive due to its high molecular strain originating from its curved structure. Here we report the construction of extended quintulene, which was unambiguously characterized by mass and NMR spectroscopy. The extended quintulene represents a naturally curved nanocarbon based on its conical molecular geometry. It undergoes dimerization in solution via π-π stacking to form a metastable, but isolable bilayer co ...[more]

PMID: 32769970

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