Synthesis and Isolation of a Kekulé Hydrocarbon with a Triplet Ground State

Angew Chem Int Ed Engl. 2022 Jul 18;61(29):e202205729. doi: 10.1002/anie.202205729. Epub 2022 May 31.

Abstract

Design, synthesis, and isolation of a Kekulé hydrocarbon with a triplet ground state is described. Its triplet ground state was unambiguously confirmed by ESR experiments, and the structure and fundamental physical properties were also revealed. The key feature of the molecular design is the decrease in the bonding interaction in the singlet state by aromatic stabilization of benzene rings and the increase of the exchange interaction of unpaired electrons which are favorable for the triplet state. These results contribute to the development of hydrocarbon-based organic magnetic materials.

Keywords: Diradicals; Hydrocarbons; Polycycles; Quinodimethanes; Triplet Ground State.