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.
Barluenga
José
J
Instituto Universitario de Química Organometálica Enrique Moles, Unidad Asociada al C.S.I.C. Julián Clavería, 8, Universidad de Oviedo, 33071-Oviedo, Spain. barluenga@sauron.quimica.uniovi.es
Fañanás
Francisco J
FJ
Sanz
Roberto
R
Marcos
César
C