Regioselective synthesis of 4,6,7-trisubstituted benzofurans from furfural imines and nonheteroatom stabilized alkynylcarbene complexes.
Nonheteroatom stabilized chromium alkynylcarbene complexes 3,6, generated in situ from Fischer cabene complexes 1, smoothly react with furan-2-ylmethanimines 4 to provide substituted 7-aminobenzofurans 5 in moderate to good yields. The procedure involves the construction of the arene ring by a regioselective [3+3] carbocyclization reaction.
Barluenga
José
J
Instituto Universitario de Química Organometálica E. Moles, Unidad Asociada al CSIC, Universidad de Oviedo, Julián Clavería, 8, E-33006 Oviedo, Spain. barluenga@uniovi.es
Gómez
Aránzazu
A
Santamaría
Javier
J
Tomás
Miguel
M