Metal‐Free Hydroxyalkylative Radical Addition/Cyclization of Unactivated Alkenes for the Synthesis of Hydroxyalkylated Ring‐Fused Quinazolinones

An efficient protocol for the synthesis of ring‐fused quinazolinone derivatives through hydroxyalkyl radical‐initiated cyclization was developed, providing a series of five‐ and six‐membered ring‐fused hydroxyl‐containing quinazolinones in moderate to good yields. This reaction was conducted under metal‐free conditions using dicumyl peroxide as the radical initiator. Notably, this is the first example of the construction of ring‐fused quinazolinones through the radical C(sp 3 )−H functionalization of simple alcohols and was successfully utilized in the synthesis of Phaitanthrin A derivative.