Thioarylative Radical Cyclization of Yne-Dienone

J Org Chem. 2019 Aug 16;84(16):10509-10517. doi: 10.1021/acs.joc.9b01445. Epub 2019 Aug 1.

Abstract

We herein demonstrated a N-hydroxyphthalimide (NHPI)-mediated chemo- and regioselective radical cyclization of yne-dienone with thiols to construct 3-thioaryl bearing [6,6]-fused dihydrochromenone derivatives. This transformation tolerates common functional groups and has broad scope. The reaction proceeds via the attack of a thioaryl radical to alkyne over the activated Michael acceptor. The TEMPO quenching experiment suggests the involvement of a radical intermediate. Synthetic versatility of 3-thioaryldihydrochromenones is also showcased.