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.
J Org Chem
; 79(5): 2075-81, 2014 Mar 07.
Article
in En
| MEDLINE
| ID: mdl-24502669
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.
Full text:
1
Database:
MEDLINE
Main subject:
Benzoin
/
Aldehydes
/
Fluorenes
Language:
En
Year:
2014
Type:
Article