Presented herein is a novel synthesis of 3-hydroxyfluorenones through the cascade reaction of aryl enaminones with benzyl substituted cyclopropanols.The formation of product is initiated by the introduction of an enon...Presented herein is a novel synthesis of 3-hydroxyfluorenones through the cascade reaction of aryl enaminones with benzyl substituted cyclopropanols.The formation of product is initiated by the introduction of an enone moiety onto aryl enaminone with cyclopropanol as a homoenolate precursor through aryl C−H bond activation,followed by intramolecular enamine Michael addition,enol Michael addition,amine elimination and aromatization-driven oxidative dehydrogenation.To our knowledge,this should be the first example for the specific synthesis of 3-hydroxyfluorenone derivatives via simultaneous formation of both indenone and phenol scaffolds through cascade C−H/C−C/C−N bond activation and three C−C bond formation.In general,this newly developed protocol features easily accessible substrates,synthetically and pharmaceutically valuable products,unique reaction pathway,good compatibility with various functional groups and ready scalability.展开更多
基金We are grateful to Postdoctoral Research Grant in Henan Province(HN2022041)Key Research Projects of Universities in Henan Province(24A150018)NMPA Key Laboratory for Research and Evaluation of Innovative Drug,Henan Key Laboratory of Organic Functional Molecules and Drug Innovation,and 111 Project(D17007)for financial support.
文摘Presented herein is a novel synthesis of 3-hydroxyfluorenones through the cascade reaction of aryl enaminones with benzyl substituted cyclopropanols.The formation of product is initiated by the introduction of an enone moiety onto aryl enaminone with cyclopropanol as a homoenolate precursor through aryl C−H bond activation,followed by intramolecular enamine Michael addition,enol Michael addition,amine elimination and aromatization-driven oxidative dehydrogenation.To our knowledge,this should be the first example for the specific synthesis of 3-hydroxyfluorenone derivatives via simultaneous formation of both indenone and phenol scaffolds through cascade C−H/C−C/C−N bond activation and three C−C bond formation.In general,this newly developed protocol features easily accessible substrates,synthetically and pharmaceutically valuable products,unique reaction pathway,good compatibility with various functional groups and ready scalability.
