The synthesis and resolution of a bulky and electron-rich derivative of SEGPhos and its application in Ru-catalyzed asymmetric hydrogenation reaction of beta-ketoesters are reported. Up to 99.5% ee was achieved. Under solvent-free reaction conditions, acetoacetates could be reduced with good enantioselectivity and high efficiency; a TON of 20 000 was obtained within 3.5 h. The results obtained were comparable to those when SEGPhos was applied.

Chiral Jacobsens catalyst was axially immobilized onto phenoxy-modified zirconium poly-A C H T U N G T R E N N U N G (styrene-phenylvinylphosphonate)phosphate (ZPS-PVPA). The immobilized catalysts show comparable ee values for asymmetric epoxidation of styrene and much higher ee values for a-methylstyrene (73.7% vs. 54.0%) and indene (99.9% vs. 65.0%) than the homogeneous Jacobsens catalyst. Moreover, the assynthesized catalysts are relatively stable and can be recycled at least five times without significant loss of activity and enantioselectivity. A point worth emphasizing is that the heterogeneous catalysts afforded remarkable increases of conversion and ee values in the absence of expensive O-coordinating axial bases for the asymmetric epoxidation of olefins, especially for the epoxidation of a-methylstyrene (conversion: from 24.3% to 99.9%; ee: from 29.4% to 73.7%), which may overcome the last obstacle for the potential industry application of chiral Jacobsens catalyst.

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