85505-03-9Relevant academic research and scientific papers
cis-Dihalobis(arylazo oxime)ruthenium(II): Synthesis, structure, and reactions
Chakravarty, Akhil R.,Chakravorty, Animesh,Cotton, F. Albert,Falvello, Larry R.,Ghosh, Barindra K.,Tomas, Milagros
, p. 1892 - 1896 (2008/10/08)
The reaction of RuX3 (X = Cl, Br) with arylazo oximes (ArN=NC(=NOH)R, HL) in boiling ethanol under a dinitrogen atmosphere affords dark crystals of composition RuX2(HL)2. In all, a group of five complexes differing in R Ar, and/or X are reported along with one iodo (X = I) complex. These are uniformly diamagnetic and display a t2(Ru) → π* (HL) charge-transfer transition near 500 nm. The complex dichlorobis(α-(phenylazo)benzaldoxime)rothenium(II) has been X-ray crystallographically characterized. The crystals belong to the orthorhombic space group Pc21n, and unit cell dimensions are a = 11.879 (3) A?, b = 12.155 (3) A?, c = 18.418 (3) A?, V = 2659 (3) A?3, and Z = 4. The RuCl2N4 coordination shell has approximate C2 symmetry. The two chlorine atoms are cis to each other, and two oxime nitrogen atoms are trans to each other. Each oxime group is involved in an N-O-H?Cl type hydrogen bond with a cis chlorine atom. The backbone of each ligand along with the chlorine atom hydrogen bonded to it is meridionally disposed and is essentially planar. The average Ru-N distance is 1.986 [2] A?, indicating that π-bonding is strong. Infrared (doublet νRuX2) and 1H NMR spectra indicate that the other complexes have cognate structures. A general reaction of RuX2(HL)2 is their facile dehydrohalogenation in the presence of bases. The complexes display a cyclic voltammetric one-electron metal oxidation peak in MeCN near 1.2 V vs. SCE. The high value of the potential is a result of the strong Ru-N π-bonding.
