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Published on: June 10, 2021
Aromatization of Benzannulated Perylene-3,9-diones: Unexpected Photophysical Properties and Reactivity
M Rajeswara Rao1, Shea Johnson1, Dmitrii F Perepichka1
1Department of Chemistry, McGill University , 801 Sherbrooke Street West, Montreal, Quebec, Canada H3A 0B8.
Abstract:
Highly unusual properties of acene-based quinones 1A and 1T are reported. They undergo an unexpected combination of Michael and carbonyl additions of aryllithium leading to new triarylated benzoperylenes 3A and 3T. Uncharacteristically for quinones, 1A and 1T display vibronically split absorption bands and small Stokes shifts. The absorption/emission spectra of the highly emissive 1A are almost indistinguishable from those of the aromatized 3A. Additional benzene rings cause a counterintuitive blue shift of the aromatic derivatives (2T/3T), but an expected red shift was observed for the quinone (1T). This behavior is fully supported by DFT calculations and rationalized by considering the longest conjugation path.
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