Wydział Chemii

Piotr Banachowicz

Mainak Das

Krzysztof Kruczała

Miłosz Siczek

Zbigniew Sojka

Monika Kijewska

Miłosz Pawlicki

2024

Angewandte Chemie - International Edition

63

e202400780/1-e202400780/9

10.1002/anie.202400780

Naukowa

Angielski

Artykuł

A diradical/biradical character of organic derivatives is one of the key aspects of contemporary research focusing on the fundamental studies followed by potential applicability relying on the unique optical, electronic, or magnetic properties assigned to unpaired electrons. A precise involvement of two p-phenylenes into a cyclophane-like conjugated, diatropic system creates a flexible molecule with the two different characters of both subunits (benzene and quinone) imprinting into the structure a Kekulé delocalized system. A dynamic of both carbocyclic subunits, and their mutual interaction generates a singlet open-shell state (J=−1.25 kcal/mol) as documented spectroscopically (NMR and EPR). The extended theoretical analysis has proved a correlation between dihedral angle and the diradicaloid character that shifts from a closed-shell singlet to an open-shell state, eventually showing the y₀=0.86 for 78 degrees and ΔE_ST=−0.34 kcal/mol.

macrocycle, Thiele's hydrocarbon, diradicaloid, pi-conjugation, phenylenes

CC-BY

http://dx.doi.org/10.1002/anie.202400780

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