Efficient Suzuki-Type Cross-Coupling of Enantiomerically Pure Cyclopropylboronic Acids

Abstract

Optically active cyclopropanes (e.g. 1) can be prepared by the use of tartaric acid derivatives as chiral auxiliaries in the palladium-catalyzed cross-coupling of optically active cyclopropylboronic acids with electrophiles. The absolute configuration of the chiral carbon atom is retained, and the reaction proceeds with good yields and enantiomeric excesses. R=H, p-Ph, o-CO₂ CH₃ , p-CO₂ CH₃ , p-NO₂ , o-OCH₃ , m-OCH₃ .