Metal-free Alkylation Via Radical Pathway

Alkylation reaction is an important aspect in the construction of C-C bond.The alkylation of carbon-carbon double bond is an important approach in the functionalization of olefins.Radical reactions,especially the metal-free ones,have attracted great attentions for their environmentally friendliness,high atom-and step-economy.In this thesis,the formation of C-C bonds and the functionalization of olefines via medical pathway under metal-free conditions were achieved.This paper contains three parts:(1)1,2-Arylalkylation of N-(arylsulfonyl)acrylamides using aliphatic aldehydes as the alkyl sourceAlkylation of N-(arylsulfonyl)acrylamides were achieved using aliphatic aldehydes as alkyl source and DTBP as the oxidant under metal-free conditions.In this reaction,sequential decarbonylation,alkylation,aryl migration and desulfonylation were involved to provide a series of?-aryl-?-alkylamides in moderate to good yields.(2)Metal-free oxidative decarbonylative alkylation of chromones using aliphatic aldehydesThe 2-alkylation of chromones were achieved with DTBP as the oxidant,aliphatic aldehydes as the alkylating agents via conjugate addition.A series of2-tertiary,secondary,and even primary alkylated chromanones were obtained in moderate to excellent yields.(3)Hydroxyalkylation of chromones via alcohol mediated radical conjugate additionA series of 2-hydroxyalkylated chromanones were obtained using DTBP as oxidant and alcohols as hydroxyalkyl sources via radical sp~3 C-H activation in moderate to good yields.Besides,ethers can also undergo similar conjugate addition to provide corresponding ether-chromanones via activation of sp~3C-H bonds adjacent to oxygen atom.