Chiral Isoxazole‐Containing Triarylmethanes through Enantioselective Nucleophilic Addition of 5‐Aminoisoxazoles to ortho‐Quinone Methides and Their Antifungal Evaluation

Enantioselective nucleophilic addition of 5‐aminoisoxazoles to ortho‐quinone methides was accomplished by using a chiral phosphoric acid as catalyst. This transformation allowed the synthesis of a range of enantioenriched isoxazole‐containing triarylmethanes. The absolute configuration of one product was determined by an X‐ray crystal structural analysis. A plausible mechanism was proposed. Moreover, several products were evaluated in antifungal activity against plant pathogenic fungi R. solani and two of them displayed promising activities.