Cyclocarbopalladation of Alkynes:  A Stereoselective Method for Preparing Dibenzoxapine Containing Tetrasubstituted Exocyclic Alkenes

A palladium-catalyzed cascade carbometalation-cross coupling of alkyne route was developed for the preparation of tetrasubstituted exocyclic alkenes with high stereo- and regiocontrol. The effectiveness of this novel methodology was demonstrated by the synthesis of a number of dibenzoxapines in sufficient quantities to support their further development.