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Updated: Jul 6, 2025

Synthesis of Hypervalent Iodonium Alkynyl Triflates for the Application of Generating Cyanocarbenes
Published on: September 8, 2013
Controllable Synthesis of N-Heterocycles via Hydride Transfer Strategy-Enabled Formal [5 + 1] and [5 + 2]
Ying Dong1, Fangzhi Hu1, Huixin Wu1
1College of Chemistry and Pharmaceutical Sciences, Qingdao Agricultural University, Changcheng Rd. #700, Qingdao 266109, P. R. China.
Abstract:
The Brønsted acid-controlled switchable synthesis of indoline-fused tetrahydroquinolines and indole-fused benzazepines was developed through hydride transfer-enabled formal [5 + 1] and [5 + 2] cyclization reactions from indoles and N-alkyl o-aminobenzoketones. Indoline, furanone, and tetrahydroquinoline hybridized pentacyclic products were unprecedentedly accessed via a cascade condensation/hydride transfer/dearomatization-cyclization/deethylation/nucleophilic addition process. In addition, the undeveloped hydride transfer-involved [5 + 2] cyclizations were also realized for direct construction of indole-fused benzazepines.
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