Metal-Free Synthesis of 2‑Oxindoles via PhI(OAc)2‑Mediated Oxidative C–C Bond Formation

The series of 3-monofunctionalized 2-oxindoles 2 were conveniently synthesized from reactions between anilide 1 and phenyliodine­(III) diacetate (PIDA) through hypervalent iodine mediated C­(sp2)–C­(sp2) bond formation followed by a subsequent deacylation reaction. This metal-free method, shown to provide direct access to an important oxindole intermediate, could be applied to the total synthesis of naturally occurring horsfiline.