Phosphine‐Catalyzed (3+2) Annulation of Morita–Baylis–Hillman Carbonates with Pyrazolinone‐Derived Ketimines: Synthesis of Spirodihydropyrrole/dihydropyrazolones
Phosphine‐Catalyzed (3+2) Annulation of Morita–Baylis–Hillman Carbonates with Pyrazolinone‐Derived Ketimines: Synthesis of Spirodihydropyrrole/dihydropyrazolones
Xi Chen,Min Liu,5 Authors,Hongchao Guo
2023 · DOI: 10.1002/ejoc.202300841
Annalen der Pharmacie · 2 Citations
Abstract
A phosphine‐catalyzed (3+2) annulation of Morita–Baylis–Hillman carbonates with pyrazolinone‐derived ketimines has been achieved to give various spirodihydropyrrole/dihydropyrazolones in moderate to high yields with good diastereoselectivities. The protocol proved to be efficient with diverse MBH carbonates and ketimines. Both scale‐up reaction and further transformation of the product were successfully. In addition, up to 98% ee of chiral product was obtained with the use of chiral bifunctional phosphine.