PtCl2-catalyzed rapid access to tetracyclic 2,3-indoline-fused cyclopentenes:: Reactivity divergent from cationic Au(I) catalysis and synthetic potential

A PtCl2-catalyzed 3,3-rearrangement/[3+2]-cycloaddition of propargylic 3-indoleacetates is developed. Besides the efficient formation of highly functionalized tetracyclic cyclopentenes, the reaction is dramatically divergent from that catalyzed by cationic Au-I. Moreover, the synthetic potential of this method is demonstrated by a succinct synthesis of the tetracyclic core of vindolinine.