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 suggest that electronic effects control the regioselectivity of the alkyne insertion step.
|Number of pages||5|
|Journal||Chemistry - A European Journal|
|Early online date||8 Apr 2016|
|Publication status||Published - 10 May 2016|
- C-H activation
- Density functional calculations
ASJC Scopus subject areas