RESUMO
Four novel N-aryl-2-thienyl substituted 1,4-diazabutadiene (alpha-diimine) ligands 5-8 have been prepared by cyanide ion-catalyzed intermolecular coupling of the appropriate aromatic aldimines. A ligand featuring a phenyl spacer moiety between a thiophene carbon atom and each imino nitrogen atom (12) has been prepared by a similar synthetic route. Ligands 5-8 and 12 were characterized on the basis of 1H and 13C NMR, IR and MS-CI spectroscopy. Upon treatment with PI3 in CH2Cl2 solution, ligands 5-8 undergo redox reactions to furnish the triiodide salts of the corresponding phosphenium cations 13-16 which were characterized by 1H, 13C and 31P NMR, and MS-CI spectroscopy. The phosphenium triiodide salt 15, and ligands 5-7 and 12 were also structurally authenticated.