Organocatalytic construction of axially chiral phosphorus-containing arylpyrazoles

In Angewandte Chemie, Wang, Song, and co-workers report a novel and practical organocatalysis methodology for accessing axially chiral pyrazole-based phosphorus scaffolds. They induced the cen-tral-to-axial chirality conversion in Huisgen-type cycloaddition by using a dipeptide-phosphonium salt catalyst under very low catalyst loading (1 mol %).