SYNTHESIS OF A STABLE BIRADICAL¹

A Stable Trimethylenemethane Triplet Diradical Based on a Trimeric Porphyrin Fused π‐System

“…Along this line, several TMM‐based stable high‐spin molecules have been developed to date . As a successful example, the Yang diradical 2 – showed both strong ferromagnetic coupling and stability similar to other typical phenoxy radicals. However, its methylene ends of TMM were located as parts of aromatic rings, hence significantly contributing to improvement of the chemical stability.…”

The Ground Spin States of Tris[p-(N-oxyl-N-tert-butylamino)phenyl] amine, -Methyl, and -Borane. Prospects of Further Studies

“…A contribution of the quinonoidal resonance forms seems to be important in strengthening the magnitude of the exchange coupling in C and 4. C may also be regarded as the aminoxyl counterpart of Yang's diradical in which the molecule has approximate D symmetry with propeller blades of quinonoidally distorted six-membered rings in the same direction (15).…”

A Triphenylamine with Two Phenoxy Radicals Having Unusual Bonding Patterns and a Closed‐Shell Electronic State

“…[1] This molecule possesses two 2,6-di-tert-butylphenoxy radical moieties directly connected to acentral methine carbon atom. [3] In this case,one of the radical spins of the three phenoxy radicals is consumed to make ac ovalent bond with the unpaired p electron of the methine carbon atom, and therefore this molecule becomes ab iradical. Thea nalogue of the galvinoxyl radical wherein the methine carbon atom is replaced by an imine nitrogen atom has been also reported to be am onoradical because of its isoelectronic structure to that of galvinoxyl (Scheme 1a).…”