Heterogeneous Jacobsen's catalyst on alkoxyl‐modified zirconium poly (styrene‐phenylvinylphosphonate)‐phosphate (ZPS‐PVPA) for asymmetric epoxidation

Abstract

Chiral Jacobsen's catalysts grafted onto alkoxyl-modified ZPS-PVPA exhibit excellent activities (conv%, up to 96; sele%, up to 96; ee%, up to >99) in the asymmetric epoxidations of unfunctionalized olefins. The superior stabilities and the comfortable dispositions in large-scale reactions contribute to the potential applications in industry.

Organic Synthesis Using Environmentally Benign Acid Catalysis

“…Similar results were obtained by Huang et al using a Jacobsen’s type catalyst bound to zirconium poly(styrene-phenylvinylphosphonate)-phosphate (ZPS-PVPA) and mCPBA/ NMO as an oxidizer [ 125 ]. The reactions proceeded with high yields and enantioselectivities and the catalyst was reused for up to seven times without notable loss of activity and enantioselectivity.…”

Asymmetric epoxidation of unfunctionalized olefins catalyzed by chiral salen‐Mn (III) immobilized on alkoxyl‐modified ZnPS‐PVPA

“…The phosphonate and phosphate stretching vibrations contribute to the adsorptions at 1200, 1145, and 1080 cm −1 . In addition, the bands at the hand of 1279 cm −1 originate from the vibration of triazole ring in the catalysts 6a ‐ d. Above all, the most informative evidence confirms the anchoring of Jacobsen's catalyst onto ZnPS‐PVPA.…”

“…The bands at 335 nm are due to the charge transfer transition of salen ligand. The bands at 435 nm originate in the ligand‐to‐metal charge transfer transition, and the bands at 515 nm are attributed to the d‐d transition of salen Mn (III) complex . The UV–vis spectras further confirm chiral Mn (III) salen complex 2 are successfully immobilized on ZnPS‐PVPA.…”