Ru-Catalyzed One-Pot Diannulation of Heteroaryls: Direct Access to π‑Conjugated Polycyclic Amides

A novel Ru-catalyzed
oxidative double annulation of heteroarenes
with symmetrical and unsymmetrical alkynes is reported. A general
method for the unsymmetrical annulation of heteroarenes with two distinct
alkynes is showcased for the first time. Methylphenyl sulfoximine
(MPS) plays an important role in the annulations of heteroarenes and
allows the construction of structurally complex π-conjugated
heteroarene-fused polycyclic amide skeletons via the formation of
multiple C–C and C–N bonds in a single operation. The
reaction exhibits excellent substrate scope and tolerates a wide range
of functional groups.