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  • Copper‐Catalyzed Enantio‐ a...
    Zhang, Liangliang; Oestreich, Martin

    Chemistry, November 13, 2019, Letnik: 25, Številka: 63
    Journal Article

    A highly stereocontrolled syn‐addition of silicon nucleophiles across cyclopropenes with two different geminal substituents at C3 is reported. Diastereomeric ratios are excellent throughout (d.r.≥98:2) and enantiomeric excesses usually higher than 90 %, even reaching 99 %. This copper‐catalyzed C−Si bond formation closes the gap of the direct synthesis of α‐chiral cyclopropylsilanes. Silicon meets strain: A robust copper‐catalyzed C−Si bond formation enables the direct synthesis of α‐chiral cyclopropylsilanes from cyclopropenes. The syn‐addition across the strained alkene occurs highly diastereo‐ and enantioselectively with discrimination of the geminal substituents at C3 (see scheme; segphos=5,5′‐bis(diphenylphosphanyl)‐4,4′‐bi‐1,3‐benzodioxol).