Palladium-Catalyzed Intermolecular Carbene Insertion Prior to Intramolecular Heck Cyclization: Synthesis of 2‑Arylidene-3-aryl-1-indanones

A domino process
that converges the migratory insertion of carbene
with a Heck reaction has been established as a versatile tool for
the synthesis of 2-arylidene-3-aryl-1-indanones from very stable and
easily accessible N-tosylhydrazones and 2′-iodochalcones.
The reaction selectively proceeds through 5-exo-trig cyclization and delivers the products selectively with
the E configuration of the double bond in excellent
yields. The one-pot synthesis of 2-arylidene-3-aryl-1-indanones involving
in situ synthesis of both 2′-iodochalcones and N-tosylhydrazones has also been demonstrated.