Cascade dearomative [4 + 2] cycloaddition of indoles with in situ generated ortho-quinone methides: practical access to divergent indoline-fused polycycles

A rationally designed cascade dearomative [4 + 2] cycloaddition of indoles with in situ generated o -QM has been developed to assemble indoline-fused polycycles divergently with high yields and excellent diastereoselectivity in one step.