| Abstract
| - To seek novel metal-free organic catalysts for epoxidationwith high stereoselectivity, a series of 4-substituted-α,α-diaryl-prolinols were synthesized in four steps from trans-4-hydroxyl-l-proline. These prolinol derivatives catalyzedthe asymmetric epoxidation of α,β-enones to give thecorresponding chiral epoxides in good yields and highenantioselectivities under mild reaction conditions. Studiesof substituent effects on enantioselectivity revealed that stericbulk and electronic effect promoted higher enantioselectivity,and prolinol 8a was found to be the best catalyst until now.
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