Diastereo- and Enantioselective Carbolithiation of Allyl <i>o</i>-Lithioaryl Ethers. New Chiral Cyclopropane Derivatives

Abstract

[reaction: see text] Different allyl 2-lithioaryl ethers undergo a tandem carbolithiation/gamma-elimination in Et(2)O/TMEDA affording o-cyclopropyl phenol or naphthol derivatives in a diastereoselective manner. The use of (-)-sparteine as a chiral ligand instead of TMEDA allows the synthesis of cyclopropane derivatives with up 81% ee.