Dendritic phosphoramidite ligands for Rh-catalyzed [2+2+2] cycloaddition reactions: unprecedented enhancement of enantiodiscrimination.

Phosphorus dendrimers containing terminal phosphoramidite ligands have been found to be highly effective and recoverable catalysts for the rhodium(I) catalyzed [2+2+2] cycloaddition reactions. A strong positive dendritic effect is observed both in the activity and enantiodiscrimination leading to axially chiral biaryl compounds.