A Luminescent Stable Triarylmethyl Diradical with an Axially Chiral Spacer.

Two units of a highly stable luminescent triarylmethyl radical (PyBTM) were bridged using a chiral octahydrobinaphthyl moiety, resulting in a diradical with sufficient stability to enable the measurement of its chiroptical properties. To synthesize this diradical, a novel boronic ester radical precursor, αH-PyBTM-B(Epin), was designed. The use of this precursor significantly improved the yield and streamlined the preparation of stable luminescent radical-substituted molecules.