Diastereo‐ and Enantioselective Synthesis of 1,2,3‐Substituted Cyclopropanes with Zinc Carbenoids

Substituted, functionalized iodoalkylzinc reagents in combination with the chiral dioxaborolane 2 give excellent diastereo- and enantiomeric selectivities in cyclopropanations when substituted allyl alcohols 1 (R1  H, Et, CH2OBn; R2  H, Ph, nPr; R3  H, Me) are used as starting materials and CH2Cl2 as solvent. This efficient preparation of chiral, nonracemic 1,2,3-trisubstituted cyclopropanes 3 might be useful in natural product synthesis.