Kinetic Stabilization of Blue‐Emissive Anthracenes: Phenylene Bridging Works Best

In attempts at kinetically stabilizing blue‐emissive anthracenes, a series of 9,10‐diaryl substituted derivatives were tested for their photochemical and photooxidative persistence. A major breakthrough in light fastness comes from a new bis‐meta‐terphenylyl substituted anthracene which is much superior to industrially relevant 9,10‐biarylated anthracenes. The key issue is the steric shielding of the anthracene core. Further, intramolecular ring closure via Yamamoto coupling furnished a doubly bridged anthracene as a “self‐encapsulated” sky‐blue emitter which is most resistant to photodegradation. The improved stabilization was corroborated by time‐resolved irradiation experiments and rationalized by X‐ray crystallography.