Journal of Organometallic Chemistry 579 (1999) 321 – 327 Synthesis and characterization of new allyl palladium complexes with thionate ligands; X-ray molecular structures of [Pd 3 ( 3 -C 4 H 7 ) 3 {pm(Me) 2 S} 2 ](CF 3 SO 3 ) and [Pd{pm(Me) 2 S} 2 ], 3 -C 4 H 7 = 3 -2-MeC 3 H 4 , pm(Me) 2 S = Pyridine-4,6-dimethyl-2-thionate Rafael Ferna ´ndez-Gala ´n a , Blanca R. Manzano a , Antonio Otero a, *, Nicolas Poujaud b , Marek Kubicki b a Departamento de Quı ´mica Inorga ´nica, Orga ´nica y Bioquı ´mica, Uniersidad de Castilla -La Mancha, Facultad de Quı ´micas, E-13071 Ciudad Real, Spain b Laboratoire de Synthe `se et dElectrosynthe `se Organome ´talliques (UMR 5632), Uniersite ´ de Bourgogne, Faculte ´ des Sciences Gabriel, 6 Bd. Gabriel, E-21000 Dijon, France Received 23 November 1998 Abstract The reaction of [Pd( 3 -C 4 H 7 )]CF 3 SO 3 ( 3 -C 4 H 7 = 3 -2-MeC 3 H 4 )(1), prepared in situ by reaction of [Pd( 3 -C 4 H 7 )Cl] 2 with AgCF 3 SO 3 , with various thionate ligands, gives new polymeric complexes formulated as [Pd( 3 -C 4 H 7 )(RS)] n (2) [RS =pyS (pyridine-2-thionate)], im(Me)S(imidazole-3-methyl-2-thionate) (3), pm(Me) 2 S (pyrimidine-4,6-dimethyl-2-thionate) (4). A solution of 4 contaminated with KCF 3 SO 3 evolves to give crystals that correspond to a new polymeric species whose X-ray crystal molecular structure indicates the presence of cationic infinite chains built of trinuclear units, [Pd 3 ( 3 -C 4 H 7 ) 3 {pm(Me) 2 S} 2 ] + (5). Finally, the formation of a mononuclear thionate-containing palladium complex [Pd{pm(Me) 2 S} 2 ](6) occurs from a solution of 5 after prolonged periods. An X-ray crystal structure determination indicates a square-planar disposition of two thionate ligands around the Pd atom. The different complexes were characterized by spectroscopic techniques. © 1999 Elsevier Science S.A. All rights reserved. Keywords: Palladium complexes; Thionate; Allyl; Pyridine-4,6-dimethyl-2-thionate; Pyridine-2-thionate; Imidazole-3-methyl-2- thionate 1. Introduction Heterocyclic thionates are ligands derived from hete- rocyclic thiones that contain at least one deprotonated heterocyclic thioamide group (NCS) - (see Chart 1) [1] and can act as monodentate, chelating and bridging ligands. The aforementioned systems have been exten- sively studied in the field of coordination chemistry [2]. After the preparation of the first complex, [Ru- Cl(pyS)(PPh 3 ) 2 ] (pyS =pyridine-2-thionate) [3], several families of thionate-containing late transition metal complexes have been described, most of which are regarded as polynuclear species with S,N -bridging lig- ands, although in recent years other coordinating modes of these ligands have been established [4]. With regard to Group 10 metals, several thionate-containing complexes of palladium have been prepared [5] and, in (Chart 1) * Corresponding author. Fax: +34-926-295-318. E-mail address: aotero@qino-cr.uclm.es (A. Otero) 0022-328X/99/$ - see front matter © 1999 Elsevier Science S.A. All rights reserved. PII:S0022-328X(99)00021-2