Samarium Diiodide Induced Cyclizations of γ-, δ- and ε-Indolyl Ketones: Reductive Coupling, Intermolecular Trapping, and Subsequent Transformations of Indolines
prepared by simple N‐alkylation or N‐acylation of indolederivatives with the corresponding iodo alkanones, acid chlorides, or lactones. After treatment of indolyl ketones with two equivalents of SmI2, the generated stabilized carbanionic intermediates were trapped with different electrophiles leading to a variety of highly substituted indolinederivatives in good to very good yields. In general, the cyclization
Here we summarise our results for SmI2-induced 5-exo-trig to 8-exo-trig reductive cyclisations of suitably substituted indole and pyrrole derivatives. All precursors were easily prepared by simple N-alkylation or N-acylation of indole and pyrrole derivatives with the corresponding iodo alkanones, acid chlorides or lactones. The SmI2-induced cyclisations in most cases provided tri- and tetracyclic derivatives