Cobalt Catalyzed, Regioselective C(sp2)-H Activation of Amides with 1,3-Diynes.

The development of a first row transition metal (cobalt)-based catalyst for the as yet unexplored C-H activation-driven reaction of 1,3-diynes, themselves a functional class of interest in a range of application areas, to form isoquinolinones-an important structural motif in a number of biologically active substances-is presented. This versatile and inexpensive catalyst employs a covalently attached bidendate-directing group, 8-aminoquinoline. The template directs the C-H activation and facilitates the synthesis of a wide range of alkynylated heterocycles under mild conditions and with excellent regioselectivity. This strategy provides a novel and efficient route to diverse heterocyclic frameworks as demonstrated by its late stage application in bisheterocycle syntheses.