A Facile and Promising Synthetic Strategy toward Functionalized 2H-Chromenes from Aryl Propargyl Ethers. A Review

Synthesis of Chalcogenylchromenes through Cyclization of Propargylic Aryl Ethers

We describe here for the first time the synthesis of 2-(chalcogenyl)-3H-benzo[f]chromenes and the new 3-(phenylselanyl)-2H-chromenes by the radical or electrophilic cyclization of propargylic aryl ethers in the presence of diorganyl diselenides or ditellurides using Oxone as a green oxidant and acetonitrile as solvent in a sealed tube at 100 °C. In this study, thirty-one chalcogenylchromenes with a broad substrate scope were prepared in moderate to excellent yields (50-98%), including compounds derived from natural products.