TMSCl–NaI-mediated reaction of aryl azides with cyclic enol ethers: An efficient one-pot synthesis of 1,2,3,4-tetrahydroquinolines

The tetrahydroquinoline moiety is an important structural component of a number of natural products. The reaction of aryl azides with 2,3-dihydro-2H-furan and 3,4-dihydro-2H-pyran in the presence of chlorotrimethylsilane-sodium iodide (TMSCl–NaI) affords the corresponding 1,2,3,4-tetrahydroquinoline derivatives in an efficient manner and most of these compounds exhibited cis selectivity. The aza-Diels–Alder reaction may proceed through in situ generation of aryl amines followed by the reaction between 2-azadiene and another equivalent of cyclic enol resulting in the formation of 1,2,3,4-tetrahydroquinolines.

Graphical abstractThe tetrahydroquinoline moiety is an important structural component of a number of natural products. The reaction of aryl azides with 2,3-dihydro-2H-furan and 3,4-dihydro-2H-pyran in presence of TMSCl–NaI affords the corresponding 1,2,3,4-tetrahydroquinoline derivatives in an efficient manner and most of these compounds exhibited cis selectivity.Figure optionsDownload full-size imageDownload as PowerPoint slide