Spirobicyclic and Tetracyclic Pyrazolidinones: Syntheses and Properties

International audienceThe stereoselective syntheses of spirobicyclic and tetracyclic pyrazolidinones are reported based on a (3+2) annu- lation between hydrazones and α-oxoketenes. Some of these conformationally constrained molecules were resolved as enantiopure materials by HPLC techniques and evaluated as amino- catalysts for iminium activation in a model Diels–Alder cyclo- addition

Spirobicyclic and Tetracyclic Pyrazolidinones: Syntheses and Properties

The stereoselective syntheses of spirobicyclic and tetracyclic pyrazolidinones are reported based on a (3+2) annu- lation between hydrazones and α-oxoketenes. Some of these conformationally constrained molecules were resolved as enantiopure materials by HPLC techniques and evaluated as amino- catalysts for iminium activation in a model Diels–Alder cyclo- addition