Asymmetric synthesis of chiral 9,10-dihydrophenanthrenes using Pd-catalyzed asymmetric intramolecular Friedel-Crafts allylic alkylation of phenols.

We developed a novel asymmetric synthetic method for multisubstituted 9,10-dihydrophenanthrenes based on the Pd-catalyzed asymmetric intramolecular Friedel-Crafts allylic alkylation of phenols, which produces 10-vinyl or 10-isopropenyl chiral 9,10-dihydrophenanthrene derivatives in high yield with up to 94% ee.