Axially Chiral Triazoloisoquinolin-3-ylidene Ligands in Gold(I)-Catalyzed Asymmetric Intermolecular (4 + 2) Cycloadditions of Allenamides and Dienes
datasetposted on 05.09.2012, 00:00 by Javier Francos, Francisca Grande-Carmona, Hélio Faustino, Javier Iglesias-Sigüenza, Elena Díez, Isaac Alonso, Rosario Fernández, José M. Lassaletta, Fernando López, José L. Mascareñas
The first highly enantioselective intermolecular (4 + 2) cycloaddition between allenes and dienes is reported. The reaction provides good yields of optically active cyclohexenes featuring diverse substitution patterns and up to three stereocenters. Key to the success of the process is the use of newly designed axially chiral N-heterocyclic carbene–gold catalysts.