Metal complexes of 3-thiophene carboxamides containing a pyridine ring

Complexes of Zn(II), Cu(II) and Co(II) with either N-(2-methylpyridyl)-3-thienyl-alkyl-carboxamide or N-(2-pyridyl)-3-thienylalkyl-carboxamide groups have been prepared and characterized. Crystal structures of ten new complexes are reported and discussed. N-(2-Methylpyridyl)-3-thienyl-alkyl-carboxamide exhibits both uni- and bidentate behavior. With all ligands, bidentate complexation is through the carbonyl oxygen and pyridine nitrogen atoms (O, N) and the amide nitrogen atom remains protonated. The electrochemical behavior and the infrared spectra of selected complexes are discussed.

Graphical abstractN-(2-Methylpyridyl)-3-thienyl-alkyl-carboxamides form O, N-bonded complexes with Cu(II), Zn(II) and Co(II) which exhibit a variety of mononuclear structures. N-(2-pyridyl)-3-thenylcarboxamide reacts with Cu(II) to form a six-coordinate O, N-complex with solvent in the apical positions.Figure optionsDownload full-size imageDownload as PowerPoint slide