Cobalt-catalyzed addition of azoles to alkynes.
A ternary catalytic system consisting of a cobalt salt, a diphosphine ligand, and a Grignard reagent promotes syn-addition of an azole C(2)-H bond across an unactivated internal alkyne with high chemo-, regio-, and stereoselectivities under mild conditions. Mechanistic experiments suggest that the reaction involves oxidative addition of the oxazolyl C-H bond to the cobalt center, alkyne insertion into the Co-H bond, and reductive elimination of the resulting diorganocobalt species.
Ding
Zhenhua
Z
Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore 637371.
Yoshikai
Naohiko
N
D000480:Alkynes / Q000737:chemistry*; D001393:Azoles / Q000737:chemistry*; D002384:Catalysis; D003035:Cobalt / Q000737:chemistry*; D015394:Molecular Structure
D000480:Alkynes; D001393:Azoles; D003035:Cobalt