1450754-01-4Relevant articles and documents
Mechanism-Driven Approach To Develop a Mild and Versatile C?H Amidation through IrIII Catalysis
Hwang, Yeongyu,Park, Yoonsu,Chang, Sukbok
supporting information, p. 11147 - 11152 (2017/08/22)
Described herein is a mechanism-based approach to develop a versatile C?H amidation protocol under IrIII catalysis. Reaction kinetics of a key C?N coupling step with acyl azide and 1,4,2-dioxazol-5-one led us to conclude that dioxazolones are much more efficient in mediating the formation of a carbon?nitrogen bond from an iridacyclic intermediate. Computational analysis revealed that the origin of higher reactivity is asynchronous decarboxylation motion, which may facilitate the formation of Ir-imido species. Importantly, stoichiometric reactivity was successfully translated into catalytic activity with a broad range of substrates (18 different types), many of which are regarded as challenging to functionalize. Application of the new method enables late-stage functionalization of drug molecules.
Ir(III)-catalyzed mild C-H amidation of arenes and alkenes: An efficient usage of acyl azides as the nitrogen source
Ryu, Jaeyune,Kwak, Jaesung,Shin, Kwangmin,Lee, Donggun,Chang, Sukbok
, p. 12861 - 12868 (2013/09/23)
Reported herein is the development of the Ir(III)-catalyzed direct C-H amidation of arenes and alkenes using acyl azides as the nitrogen source. This procedure utilizes an in situ generated cationic half-sandwich iridium complex as a catalyst. The reaction takes place under very mild conditions, and a broad range of sp2 C-H bonds of chelate group-containing arenes and olefins are smoothly amidated with acyl azides without the intervention of the Curtius rearrangement. Significantly, a wide range of reactants of aryl-, aliphatic-, and olefinic acyl azides were all efficiently amidated with high functional group tolerance. Using the developed approach, Z-enamides were readily accessed with a complete control of regio- and stereoselectivity. The developed direct amidation proceeds in the absence of external oxidants and releases molecular nitrogen as a single byproduct, thus offering an environmentally benign process with wide potential applications in organic synthesis and medicinal chemistry.
