A Versatile, Traceless C–H Activation-Based Approach for the Synthesis of Heterocycles

A versatile, traceless C–H activation-based approach for the synthesis of diversified heterocycles is reported. Rh­(III)-catalyzed, N-amino-directed C–H alkenylation generates either olefination products or indoles (in situ annulation) in an atom- and step-economic manner at room temperature. The remarkable reactivity endowed by this directing group enables scale-up of the reaction to a 10 g scale at a very low catalyst loading (0.01 mol %/0.1 mol %). Ex situ annulation of olefination product provides entry into an array of heterocycles.