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Ruthenium-azoimine-chloranilates Synthesis, Spectra and Electrochemistry of Ruthenium(II)-1-alkyl-2-(arylazo)imidazole-chloranilate Complexes

“…The modification has been carried out by the synthesis of the ruthenium-RQ system using electron donor/acceptor coligands. RQ may be modified by incorporating substituents with different electronic properties, or by replacing one or both O-donor centers [16] by NH or S. Polyoxo carbon compounds like 2,5-dihydroxy-1,4-benzoquinone (H 2 L), and other derivatives like the chloro substitutent (chloranilic acid, H 2 CA) are also good candidates for synthesising the metal-RQ series of complexes [25][26][27][28][29][30][31][32][33][34][35]. Because of the presence of equivalent O,O-donor centers on either side of the aromatic backbone of L 2) , the isolation of monomeric complexes is difficult.…”

“…Because of the presence of equivalent O,O-donor centers on either side of the aromatic backbone of L 2) , the isolation of monomeric complexes is difficult. However, some mononuclear complexes are summarized in references [26] and [32][33][34][35]. They are all considered as candidates for a synthon of supramolecular assemblies because of metal free oxygen sites.…”

“…Pseudo-octahedral dichloro-bis-chelated arylazoheterocycles of ruthenium(II) can exist, in principle, in five isomeric forms, and out of them three isomers have been structurally characterized [24][25][26][27][28][29][30][31][32][33][34][35]. The stereoisomeric forms having the cis-RuCl 2 moiety in cis-trans-cis-RuCl 2 {2-(arylazo)(pyridine)} 2 exhibit potential antitumor activity even better than does cis-platin.…”

Coupling of Arylamines with Coordinated Arylazopyrimidines in Palladium(II) Complexes

“…The observed trend of the band maxima (λ max ) for the substituent in the aryl ring follows as p-chloroaniline (6) Ͻ aniline (3) Ͻ p-toluidine (4) Ͻ p-anisidine (5). The electron-donating substituent in the X-C 6 H 4 -N-fragment increased the energy of the HOMO [27,28] and in p-anisidine the energy was maximised. In p-choloroaniline the energy of the HOMO was reduced due to the electron-withdrawing effect of the Cl group.…”

“…[19,27] A sharp single band at 1400Ϫ1415 cm Ϫ1 corresponding to ν NϭN in the ligand is shifted to 1380Ϫ1385 cm Ϫ1 in Pd(aapm)Cl 2 . This lowering of the frequency is due to N-coordination.…”