Novel Use of Selectfluor™ for the Synthesis of cis-Fused Pyrano- and Furanotetrahydroquinolines

Abstract

Aryl imines formed in situ from aryl aldehydes and aromatic amines undergo smooth [4 + 2] cycloaddition reactions with cyclic enol ethers such as 3,4-dihydro-2H-pyran and 2,3-dihydrofuran in the presence of 10 mol % Selectfluor™ in acetonitrile at room temperature to afford pyrano- and furanotetrahydroquinoline derivatives in excellent yields with high endo-selectivity.