title: Changing the reaction pathway by NHC/Brønsted base cooperative catalysis: highly stereoselective synthesis of multifunctional benzo[a]fluoren-11-ones from the dimerization of 2-(aroylvinyl)arylaldehydes.
abstract: The unprecedented NHC/Brønsted base-cocatalyzed dimerization reaction of 2-(aroylvinyl)arylaldehydes was reported. In the presence of a triazole carbene catalyst alone, no reaction of 2-(aroylvinyl)arylaldehydes was observed. However, the combination of triazole carbene and 4-methoxyphenolate efficiently catalyzed the dimerization of 2-(aroylvinyl)arylaldehydes to proceed through a benzoin-Michael-Michael reaction cascade, producing 6-aroyl-5-(aroylmethyl)-11a-hydroxybenzo[a]fluoren-11-ones as the sole diastereomers in good yields.
authors: College of Chemistry, Beijing Normal University , Beijing 100875, People's Republic of China.
authors: Yuan-feng
authors: YF
authors: Tong
authors: Jian-hui
authors: JH
authors: Mao
authors: Song
authors: S
authors: Wu
authors: Yuan
authors: Y
authors: Zhao
authors: Ying
authors: Y
authors: Cheng
mesh_terms: D000447:Aldehydes / Q000737:chemistry*; D001573:Benzoin / Q000737:chemistry*; D002384:Catalysis; D019281:Dimerization; D005449:Fluorenes / Q000138:chemical synthesis* / Q000737:chemistry*; D015394:Molecular Structure; D013237:Stereoisomerism
chemical_list: D000447:Aldehydes; D005449:Fluorenes; D001573:Benzoin