Fe-Catalyzed Hydrocyclization of Inactivated Alkenes to Synthesize Ring-Fused 2,3-Dihydroquinazolinone

A Fe-catalyzed hydrocyclization reaction of unactivated alkenes was developed, utilizing PhSiH3 as the hydrogen source, yielding 2,3-dihydroquinazolinone (DHQZ) derivatives in moderate to good yields. Notably, when the substrate was switched to N-cyano-N-(2-(prop-1-en-2-yl)phenyl)benzamides, the reaction yielded only the unreduced products. Mechanistic studies revealed that the intramolecular addition of the in situ formed radical to the unactivated alkene results in the formation of the fused ring.