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Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
Fe-Catalyzed Hydrocyclization of Inactivated Alkenes to Synthesize Ring-Fused 2,3-Dihydroquinazolinone
Youlu Pan1, Chaonan Tang1, Xianming Zeng1
1School of Pharmacy, Hangzhou Medical College, 8 Yikang Road, Hangzhou 311300, PR China.
Abstract:
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.
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