title: Photoinduced three-component reactions of tetracyanobenzene with alkenes in the presence of 1,3-dicarbonyl compounds as nucleophiles.
abstract: Photoinduced three-component reactions between tetracyanobenzene (TCNB), an aromatic olefin, and a beta-dicarbonyl compound afford products composed of the three components via formal elimination of hydrogen cyanide, leading to the vicinal dialkylation of the olefin and the alpha-alkylation of the beta-dicarbonyl compounds. It is shown that these reactions are initiated by photoinduced electron transfer (PET) from the olefin to the singlet excited TCNB and proceed by a nucleophile-olefin combination, aromatic substitution (NOCAS) reaction sequence with the enolized beta-dicarbonyl compound as a nucleophile. Therefore, aromatic olefins are suitable substrates in photo-NOCAS reactions when TCNB is used as the electron acceptor. In addition, these results show that the enol of beta-dicarbonyl compound serves as a carbon nucleophile to trap the alkene cation radical in PET reactions to lead to C-C bond formation.
authors.affiliation: School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, People's Republic of China.
authors.forename: Zhi-Feng
authors.initials: ZF
authors.lastname: Lu
authors.forename: Yong-Miao
authors.initials: YM
authors.lastname: Shen
authors.forename: Jia-Jun
authors.initials: JJ
authors.lastname: Yue
authors.forename: Hong-Wen
authors.initials: HW
authors.lastname: Hu
authors.forename: Jian-Hua
authors.initials: JH
authors.lastname: Xu