Stereodivergent Synthesis of Chiral Spiropyrazolones through Pd-Catalyzed Asymmetric Sequential Hydroalkylation of 1,3-Enynes: Unusual Solvent Effect on the Enantioselectivity

Chiral spiropyrazolones were constructed through Pd-catalyzed asymmetric sequential hydroalkylation of 1,3-enynes. Four stereoisomers could be obtained through substrate control and chiral ligand control.