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Please login to access the full content or check if you have access via Method 7: Enantioselective Hydrobromination of Epoxides Using Azidotrialkylsilanes and Allyl Bromide

DOI: 10.1055/sos-SD-035-00442

Rück-Braun, K.; Freysoldt, T.Science of Synthesis, (200735511.

The desymmetrization of meso-epoxides to provide trialkylsilyl-protected bromo alcohols is possible by using a zirconium complex with homochiral amine ligands, i.e. 1,1,1-nitrilotripropan-2-ol.[‌45‌] The reaction is carried out in the presence of azidotrimethylsilane and allyl bromide. In the first step, azidotrimethylsilane converts the precatalyst 35 into a zirconium azide intermediate [Zr2(CO2CF3)(N3)L2]; bromide, derived from allyl bromide, then replaces the azide. The activated bromide subsequently reacts with the epoxides 36 to give trialkylsilyl-protected bromo alcohols 37 in good yields and enantioselectivities (Scheme 15).

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