title: Annulation of α,β-unsaturated imines and alkynes via cobalt-catalyzed olefinic C-H activation.
abstract: A cobalt-triarylphosphine catalyst promotes an annulation reaction of an α,β-unsaturated imine and an internal alkyne to afford a polysubstituted dihydropyridine derivative in good yield under mild conditions. The reaction likely involves alkenylation of the olefinic C-H bond via cobalt-mediated nitrogen-assisted C-H activation followed by facile 6π electrocyclization of the resulting azatriene intermediate.
authors.affiliation: Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Yamakawa
authors.forename: Naohiko
authors.initials: N
authors.lastname: Yoshikai