Polycyclic motif engineering in cyanostilbene-based donors towards highly efficient modulable emission properties in two-component systems

Cynostilbene based two-component materials are fabricated which exhibit tunable structures and excellent photophysical properties depending on the IP of the polycyclic moiety and organization of the donor-acceptor in the condensed phase.

Synthesis of (E,E)-Dienones and (E,E)-Dienals via Palladium-Catalyzed γ,δ-Dehydrogenation of Enones and Enals

A new strategy for the synthesis of conjugated (E,E)-dienones and (E,E)-dienals via a palladium-catalyzed aerobic γ,δ-dehydrogenation of enones and enals has been developed. The method can be employed in the direct and efficient synthesis of various (E,E)-dienones and (E,E)-dienals, including non-substituted α-, β-, and γ- and/or δ-substituted (E,E)-dienones and (E,E)-dienals. The protocol is featured by the ready accessibility and elaboration of the starting materials, good functional group compatibility, and mild reaction conditions. Furthermore, the reaction is of complete E,E-stereoselectivity and uses molecular oxygen as the sole clean oxidant.

Palladium-catalysed atom-economical synthesis of conjugated dienals from terminal acetylenes and acrolein

Conjugated (E,E)-dienals are versatile synthetic intermediates owing to their trifunctional, electrophilic nature and the prevalence of the (E,E)-diene in a wide range of functional molecules. It is shown herein that (E,E)-dienals can be readily prepared in two palladium-catalysed steps from simple, unactivated starting materials; terminal acetylenes and acrolein can be coupled via conjugate addition, followed by alkyne isomerisation. This procedure provides a highly atom-economical, redox-neutral and practical method to prepare a range of conjugated (E,E)-dienals in good yields and diastereoselectivities.