A Highly Efficient Palladacycle Catalyst for Hydrophenylation of C-, N-, and O-Substituted Bicyclic Alkenes under Aerobic Condition

A new phosphine-free palladacycle catalyst 4 was prepared from benzyl oxazoline in high yield and fully characterized. With it as catalyst, hydrophenylation reactions of a wide range of bicyclic alkenes, not only norbornene and norbornadiene but also oxa- and aza-bicyclic alkenes, with iodobenzene proceeded smoothly under aerobic condition without exclusion of water. Up to 1.7 x 10(6) TON as well as 1.2 x 10(5) TOF were achieved.