Pyboxes are a direct evolution of box ligands and take advantage from the C2-symmetry to reduce the number of possible configurations of the reacting complex formed from ligand, Lewis acid (a cation), and one of the reagents involved in the reaction. A comparison of complexed box and pybox showed that the binding site of pybox is suitable to host Ln cations that become the Lewis acids of election in pybox-based chiral catalysts, in contrast to the failure of Ln-box complexes. It also increased rigidity of the pybox scaffold when the ligand behaves as tridentate, rigidity that is further increased in the reacting complex with reagents behaving as bidentate.
Pyridine-2,6-bis(oxazolines), Helpful Ligands for Asymmetric Catalysts
DESIMONI, GIOVANNI;FAITA, GIUSEPPE;QUADRELLI, PAOLO
2003-01-01
Abstract
Pyboxes are a direct evolution of box ligands and take advantage from the C2-symmetry to reduce the number of possible configurations of the reacting complex formed from ligand, Lewis acid (a cation), and one of the reagents involved in the reaction. A comparison of complexed box and pybox showed that the binding site of pybox is suitable to host Ln cations that become the Lewis acids of election in pybox-based chiral catalysts, in contrast to the failure of Ln-box complexes. It also increased rigidity of the pybox scaffold when the ligand behaves as tridentate, rigidity that is further increased in the reacting complex with reagents behaving as bidentate.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
