www.elsevier.nl/locate/ica Inorganica Chimica Acta 294 (1999) 87 – 94 Note Cadmium(II) complexes with [(4-methylphenyl)sulfonyl]-2-pyridyl-amine: crystal structures of bis{[(4-methylphenyl)sulfonyl]-2-pyridyl-amide}cadmium(II); aquo- bis(pyridine) bis{[(4-methylphenyl)sulfonyl]-2-pyridyl-amide}- cadmium(II) and 1,10-phenanthroline bis{[(4-methylphenyl)- sulfonyl]-2-pyridyl-amide}cadmium(II) Santiago Cabaleiro a , Ezequiel Va ´zquez-Lo ´ pez a , Jesu ´ s Castro a , Jose ´ A. Garcı ´a-Va ´zquez b , Jaime Romero b , Antonio Sousa b, * a Departamento de Quı ´mica Inorga ´nica, Uniersidade de Vigo, E-36200 Vigo, Galicia, Spain b Departamento de Quı ´mica Inorga ´nica, Uniersidade de Santiago de Compostela, E-15706 Santiago de Compostela, Galicia, Spain Received 7 May 1999; accepted 29 June 1999 Abstract Electrochemical oxidation of cadmium in a solution of [(4-methylphenyl)sulfonyl]-2-pyridyl-amine (HL) in acetonitrile/ dichloromethane afforded the compound [CdL 2 ]. When pyridine (py), 2,2-bipyridine (bipy) or 1,10-phenanthroline (phen) was added to the electrolytic phase, [CdL 2 py 2 (H 2 O)], [CdL 2 bipy] and [CdL 2 phen] were obtained. The crystal structures of [CdL 2 ](1), [CdL 2 py 2 (H 2 O)] (2) and [CdL 2 phen] (3) have been determined by X-ray diffraction techniques. The complex [CdL 2 ] is best described in terms of a linear polymer with the metal atom in a [CdN 4 O 2 ] distorted octahedral environment. The [CdL 2 py 2 (H 2 O)] and [CdL 2 phen] complexes are monomeric, with the cadmium atoms in [CdN 6 O] distorted pentagonal bipyramid and [CdN 6 ] trigonal prismatic environments, respectively. © 1999 Elsevier Science S.A. All rights reserved. Keywords: Crystal structures; Electrochemistry; Cadmium complexes; Amide complexes 1. Introduction Electrochemical procedures have been widely used for the synthesis of metallic complexes, especially of those of weakly acid organic ligands [1–5]. Of particu- lar relevance to the present work are metal complexes with heterocyclic ligands such as pyridine derivatives, (I), containing, apart from the nitrogen atom, sulfur [6,7], oxygen and sulfur [8] or selenium [9] atoms as additional donor atoms. We have now extended our previous work to the electrochemical synthesis of cadmium(II) complexes with a ligand of type (I) bearing a secondary amide (X =NR) group. Although it is well known that metal complex formation by metal substitution of the amide proton is not an easy process [10], the presence of an * Corresponding author. Tel.: +34-981-563 100; fax: +34-981- 597 525. E-mail addresses: fojo@uvigo.es (J. Castro), qiansoal@usc.es (A. Sousa) 0020-1693/99/$ - see front matter © 1999 Elsevier Science S.A. All rights reserved. PII:S0020-1693(99)00265-0