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Three wrongs make a right: a computational investigation of [4n]-[4n]-[4n] fused π-systems
Muhammad Usama Gul Khan1, Katarzyna Młodzikowska-Pieńko2, Renana Gershoni-Poranne2
1Department of Chemistry, University of Houston Houston Texas 77204-5003 USA.
Abstract:
Fusing antiaromatic units to other antiaromatic units could afford delocalized [4n]-[4n]-[4n] π-systems with reduced paratropicity (or even weak diatropicity), while retaining narrow HOMO-LUMO gaps. Through a computational investigation of bis-annelated borole-fused cyclobutadiene, pentalene, s-indacene, and cyclooctatetraene isomers, we find that these effects are topology-dependent. Comparisons to analogous [4n + 2]-[4n]-[4n + 2] systems show that [4n]-[4n]-[4n] fusion represents a counterintuitive design strategy to access functional antiaromatic π-systems.
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