Chiral Hydroxytetraphenylene–Boron Complex Catalyzed Asymmetric Diels–Alder Cycloaddition of 2′-Hydroxychalcones

( S )-2,15-Cl 2 -DHTP–boron complex catalyst for the asymmetric Diels–Alder cycloaddition of 2′-hydroxychalcones and dienes was developed and tested. The resulting cyclohexenes with three chiral centers were obtained in high yields (up to 98%) with excellent stereoselectivities (up to >20:1 endo / exo, >99% ee). This catalytic system features high efficiency, broad substrate scopes, and mild reaction conditions. In addition, a DFT study was performed to explain the stereochemical course of the asymmetric induction.