Diastereo- and enantioselective carbolithiation of allyl o-lithioaryl ethers. New chiral cyclopropane derivatives.

[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.