Cobalt-Catalyzed Oxidase C−H/N−H Alkyne Annulation: Mechanistic Insights and Access to Anticancer Agents
作者:Ruhuai Mei、Hui Wang、Svenja Warratz、Stuart A. Macgregor、Lutz Ackermann
DOI:10.1002/chem.201601101
日期:2016.5.10
Cp*‐free cobalt‐catalyzed alkyne annulations by C−H/N−H functionalizations were accomplished with molecular O2 as the sole oxidant. The user‐friendly oxidase strategy proved viable with various internal and terminal alkynes through kinetically relevant C−H cobaltation, providing among others step‐economical access to the anticancer topoisomerase‐I inhibitor 21,22‐dimethoxyrosettacin. DFT calculations
An intermolecular nickel-catalyzedaddition reaction has been developed where N-arylphthalimides react with alkynes to afford substituted isoquinolones. A mechanistic rationale is proposed, implying nucleophilic attack of Ni(0) to an amide as the primary step of the catalytic cycle.