The production of class-II mixed-valence complexes in the redox reaction between dithiomalonamide and platinum(IV) or palladium(IV)

Electrical conductive coordination polymers

“…Thus, the group of Castan explored the coordination modes of a variety of thioureas, thioamides, dithiomalonamides and related ligands combined with Pd and Pt cations during the early 80's. [65][66][67] In this way, they showed that the dithiomalonamide skeleton (HL) complexes both Pd and Pt to form two different series of mixed-valence species which are best formulated as [M II (HL) 2 ][M IV X 6 ] and [M II (HL) 2 ]-[M IV (HL) 2 X 2 ]X 4 (M = Pt and Pd; X = Cl, Br and I), as depicted in Fig. 6.…”

Emergence of Palladium(IV) Chemistry in Synthesis and Catalysis

“…Palladium complexes exist predominantly in three oxidation states: Pd 0 , Pd II , and Pd IV , although both Pd I and Pd III are known. Practically all characterized complexes in the Pd IV oxidation state are octahedral and diamagnetic with a low-spin t 2g 6 configuration. Pd IV complexes have traditionally been described as rare and elusive as compared to the both thermodynamically stable and kinetically inert Pt IV complexes.…”

“…Evidence for electronic interactions within the chains has been obtained from electrical conductivity and spectroscopy measurements. 27,28 A onedimensional mixed-valence complex [Pd II L] [Pd IV Cl 2 L]-(ClO 4 ) 4 (L ) 1,4,8,11-tetraazacyclotetradecane) has been reported. 29 In order to stabilize the…”

“…The simplest and the best characterized examples of inorganic Pd IV compounds are the [PdX 6 ] 2− anions (X = F, Cl, Br); the chloro and bromo complexes are readily prepared by halogen oxidation of solutions of the Pd II analogues. – Interestingly, crystallographic studies show that in [PdCl 4 ] 2− and [PdCl 6 ] 2− the palladium atom has effectively the same atomic radius . [PdF 6 ] 2− has been used to stabilize O 2 + salts; , Pd IV tellurato complexes have been studied as multielectron oxidants.…”

“…While Pd IV compounds themselves are diamagnetic, halogen-bridged mixed valence Pd II −Pd IV complexes show very interesting one-dimensional electronic properties. , They consist of square-planar Pd II species and tetragonal−bipyramidal Pd IV species alternately arranged in ···Pd II ···X−Pd IV −X···Pd II chains. Evidence for electronic interactions within the chains has been obtained from electrical conductivity and spectroscopy measurements. , A one-dimensional mixed-valence complex [Pd II L] [Pd IV Cl 2 L](ClO 4 ) 4 (L = 1,4,8,11-tetraazacyclotetradecane) has been reported . In order to stabilize the ···Pd II ···Pd IV ··· chains with NH···O···HN hydrogen bonds, other tetradentate nitrogen ligands have also been used …”