Enantioselective synthesis of planar-chiral metacyclophanes through rhodium-catalyzed alkyne cyclotrimerization

We have achieved the first catalytic enantioselective synthesis of planar-chiral metacyclophanes by means of cationic rhodium(I)/(R)-H-8-BINAP complex-catalyzed alkyne cyclotrimerization. This reaction represents a versatile new method for the preparation of planar-chiral [7]-[10] metacyclophanes.