نبذة مختصرة : Allylboron reagents are popular in synthesis owing to their versatility and the predictable stereochemical outcomes of their reactions with carbonyl compounds. Herein, we describe the synthesis of ( Z , Z )‐hexadienyl bis‐boronate 1 , a configurationally stable, crystalline, and easy to handle compound, which represents a class of bis‐allylic boron reagents with heretofore untapped synthetic potential. In combination with a chiral phosphoric acid catalyst, the reagent can be employed for the enantioselective allyl transfer reaction to a variety of one‐pot transformations, enabling swift access to functionalized 1, n ‐diols. The in situ conversion of the reagent into the corresponding bis‐borinic ester allows for the direct and diastereoselective two‐fold allyl transfer to aldehydes. This affords C 2 ‐ or C i ‐symmetric stereotetrads containing a 1,4‐diol moiety for natural product synthesis. The usefulness of our method was demonstrated with a short synthesis of the lignan (±)‐neo‐olivil.
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