Pd(II)/^<i>t</i>Bu-quinolineoxazoline: An Air-Stable and Modular Chiral Catalyst System for Enantioselective Oxidative Cascade Cyclization

An air-stable and structurally tunable chiral tBu-quinolineoxazoline/Pd(II) catalyst system has been developed for the enantioselective oxidative cascade cyclization of a variety of disubstituted olefinic substrates, with the apparent advantages of good yields and excellent enantioselectivities (up to 98% ee) and diastereoselectivities (dr >24:1). A transition-state model has also been proposed to account for the excellent stereocontrol.