An expedient, catalytic method for the synthesis of diverse azaindoles and indoles, starting from readily available and inexpensive starting materials, is described. Conditions were developed for effective reductive alkylation of electron-deficient o-chloroarylamines, substrates previously viewed as poor partners in this reaction. The derived N-substituted o-chloroarylamines were elaborated to azaindoles and indoles via a novel one-pot process comprised of copper-free Sonogashira alkynylation and a base-mediated indolization reaction.

An efficient regioselective method for the preparation of structurally diverse imidazopyridinones and benzoimidazolones starting from readily available and economical starting materials is described. High yielding reductive alkylation of electron-deficient o-haloarylamines followed by treatment with inexpensive N-chlorosulfonyl isocyanate afforded primary ureas in good overall yields. A Pd-catalyzed urea cyclization reaction furnished imidazopyrimidones and benzoimidazolones in excellent yields.  Overall, the developed chemistry provides rapid access to pharmaceutically important heterocycles with high efficiency.