Rhodium-catalyzed C–H activation of hydrazines leads to isoquinolones with tunable aggregation-induced emission properties

Abstract

Using an internally oxidizing directing group (DG) strategy, we report a Rh(III)-catalyzed synthesis of isoquinolones via C-H activation/annulation of benzoylhydrazines and alkynes. Tunable double cascade cyclization of benzoylhydrazines with two equivalents of alkynes led to tetracyclic amides. These N-heterocycles demonstrated adjustable AIE properties.

A comprehensive overview of directing groups applied in metal-catalysed C–H functionalisation chemistry

“…The resulting products have large conjugated π-systems and the authors also investigated their photophysical properties. 338 …”

Transition Metal‐Catalyzed Intermolecular Cascade C−H Activation/Annulation Processes for the Synthesis of Polycycles

“…Control experiments indicated that this transformation is a stepwise process and that isoquinolone is the key intermediate. Inspired by their works, Zhao, [23] Shi [24] and Dong [25] independently investigated Rh III ‐catalyzed cascade double C−H activation/annulation for the synthesis of the same type of tetracyclic products using different directing groups (Scheme 4).…”

Comprehensive Strategies for the Synthesis of Isoquinolines: Progress Since 2008

“…Both symmetrical and unsymmetrical alkynes were well tolerated under the optimized reaction conditions by giving corresponding products with high regioselectivity (Scheme 195). [201] In addition, authors have also demonstrated the one pot double cascade reaction to give structurally more complex polycyclic heterocycles. The scope of the reaction is diversified to have wide range of substituents on isoquinolone ring (Scheme 196).…”

“…Both symmetrical and unsymmetrical alkynes were well tolerated under the optimized reaction conditions by giving corresponding products with high regioselectivity (Scheme 195). [201] …”