Ferrocene-Based Chiral Phosphine-Triazines: A New Family of Highly Efficient P,N Ligands for Asymmetric Catalysis
نویسندگان
چکیده
The presence of the additional heterocyclic nitrogen atoms in chiral P,N ligands has an important influence on the asymmetric catalysis, and a clear trend was observed in the present research that the enantioselectivity and reactivity were significantly increased by raising the number of heterocyclic nitrogen atoms in these P,N ligands. Through finely tuning the number of heterocyclic nitrogen atoms, a new family of ferrocene-based chiral phosphine-triazine ligands with three heterocyclic nitrogen atoms has been developed and successfully applied in Pd-catalyzed asymmetric allylic substitution. Up to 99% ee with 99% yield of allylic alkylation products and 94% ee of allylic amination products have been obtained by the use of ligand (Rc,Sp)-1f with a 4,6-diphenoxy1,3,5-triazine moiety.
منابع مشابه
An efficient and highly stereoselective synthesis of new P-chiral 1,5-diphosphanylferrocene ligands and their use in enantioselective hydrogenation.
An efficient and highly stereoselective synthesis of P-chiral 1,5-diphosphanylferrocene ligands has been developed, and the introduction of P-chirality in ferrocene-based phosphine ligands enhances the enantioselective discrimination produced by the corresponding catalyst when matching of the planar chirality, the chirality at carbon and the chirality at phosphorus occurs.
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