Chrysene‐Based Blue Emitters

Abstract

Chrysenea nd its bisbenzannulated homologue, naphtho[2,3-c]tetraphene,w ere synthesized through a PtCl 2-catalyzed cyclization of alkynes, which also furnished corresponding biaryls subsequentt oaGlaser couplingr eaction of the startinga lkynes.T he optoelectronic properties of 5,5'-bichrysenyl and 6,6'-binaphtho[2,3-c]tetraphene were compared to their chrysene-based "monomers". Oxidative cyclodehydrogenations of bichrysenyl andi ts higher homologue towardsl arge nanographenes were also investigated.

Tethering Three Radical Cascades for Controlled Termination of Radical Alkyne peri-Annulations: Making Phenalenyl Ketones without Oxidants

“…Presumably the increased rigidity of the π-extended phenalenones derivatives decreases the nonradiative decay rates and increases the emission quantum yield. The lower emission quantum yield of 4c , relative to 4a and 4b , is consistent with the assigned fluorophoric core in Figure c where chrysene emitters are typically less efficient than their benz­[ a ]-anthracene counterparts …”

“…The lower emission quantum yield of 4c, relative to 4a and 4b, is consistent with the assigned fluorophoric core in Figure 6c where chrysene emitters are typically less efficient than their benz[a]-anthracene counterparts. 168 ■ CONCLUSIONS One does not need an oxidant to direct alkyne radical annulation cascades to the formation of formally oxidized products (e.g., phenalenyl ketones). The oxidized partially aromatized products can be selectively obtained without the addition of an oxidant via a controlled termination strategy.…”

Synthesis and Absorption Properties of Long Acenoacenes

“…To the best of our knowledge, there are only few scattered examples of class AA-I described in the literature. [15][16][17][18] Very recently, Bunz et al have prepared series of azanalogues of bisanthracene, bistetracene and bispentacene. [19] The synthesis of larger homologues becomes very challenging due to the increasing reactivity with increasing length which is amplified by low solubility in the case of unsubstituted compounds due to strong intermolecular π-π stacking.…”