Palladium‐Catalyzed Oxidative Cyclization of Enynes with Hydrogen Peroxide as the Oxidant

Gently does it: The Pd-catalyzed oxidative cyclization of enynes with hydrogen peroxide, a simple, inexpensive, and environmental benign oxidant, is proposed to proceed through a catalytic PdII/PdIV cycle in which the key CCl bond-forming step is the formation of a PdIV intermediate (see scheme). This is followed by a direct reductive elimination to generate CCl bonds with retention of the configuration of the C(sp3) center.