TY  - JOUR
A1  - Schnitzlein, Matthias
A1  - Mützel, Carina
A1  - Shoyama, Kazutaka
A1  - Farrell, Jeffrey M.
A1  - Würthner, Frank
T1  - PAHs Containing both Heptagon and Pentagon: Corannulene Extension by [5+2] Annulation
T2  - European Journal of Organic Chemistry
N2  - Utilizing Pd‐catalyzed [5+2] annulation a series of heptagon‐extended corannulenes could be synthesized from a borinic acid precursor furnished by C−H borylation strategy. Single‐crystal X‐ray analysis revealed the presence of two conformational enantiomers crystallizing in a racemic mixture. Through their embedded five‐ and seven‐membered rings these polycyclic aromatic hydrocarbons (PAHs) exhibit both negative and positive curvature and UV/Vis/NIR absorption spectroscopy as well as cyclic voltammetry experiments provided insights into the influence of larger flanking aromatic systems and electron‐donating substituents encompassing the heptagonal ring. Through [5+2] annulation of acenaphthylene an azulene‐containing PAH with intriguing optoelectronical properties including a very small bandgap and absorption over the whole visible spectrum could be obtained. Theoretical calculations were employed to elucidate the long‐wavelength absorption and aromaticity.
KW  - annulation
KW  - aromaticity
KW  - azulene
KW  - Corannulene
KW  - polycyclic aromatic hydrocarbons
Y1  - 2022
UR  - https://opus.bibliothek.uni-wuerzburg.de/frontdoor/index/index/docId/26262
UR  - https://nbn-resolving.org/urn:nbn:de:bvb:20-opus-262627
VL  - 2022
IS  - 5
ER  -