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Kinetically Blocked Stable 5,6:12,13-Dibenzozethrene: A Laterally π-Extended Zethrene with Enhanced Diradical
Priya Yadav1, Soumyajit Das1, Hoa Phan1
1Department of Chemistry, National University of Singapore , 3 Science Drive 3, Singapore 117543.
Abstract:
Although the ground-state and physical properties of zethrene and recently invented 1,2:8,9-dibenzozethrene have been well studied, the other dibenzozethrene isomer, i.e., 5,6:12,13-dibenzozethrene, remained unexplored. A short synthetic route to a kinetically blocked stable 5,6:12,13-dibenzozethrene derivative 5 is presented. The ground state is found to be open-shell singlet experimentally, and the theoretical y0 was enhanced to 0.414, which corroborates nicely with the experimental and theoretical singlet-triplet energy gap.
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