The catalytic asymmetric synthesis of terminal epoxides and 1,2-diols via a hydrolytic kinetic
resolution of racemic terminal epoxides using a new bimetallic chiral salen CoIII complex incorporated
with La(OTf)3 as a catalyst is reported. The new bimetallic chiral salen CoIII complex bearing
La(OTf)3 was prepared in a one-pot procedure by activation and bimetallic complex formation from
the inactive Jacobsen chiral salen CoII complex (salen = N, N′-bis(3,5-di-tert-butylsalicylidene)-1,2-
cyclohexane-diamine). We observed that C1-symmetric chiral bimetallic Co-complex coordinated with
La(OTf)3 works as a chiral catalyst and remarkably increased the reactivity and enantioselectivity in
the hydrolytic kinetic resolution of terminal epoxides compared to its monometallic analogues.
La(OTf)3 plays a crucial role as an achiral Lewis acid in this process, which is supported by the experimental
observation presented. To explore the absolute configuration of glycidyl butyrate a vibrational
circular dichroism (VCD) spectra was calculated using density functional theory.
Keywords: Chiral epoxides, asymmetric catalysis, bimetallic chiral salen complex, hydrolytic kinetic resolution, lewis acid,
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