642932-84-1Relevant articles and documents
Photochemical isomerization of trans- to cis-[RuCl2(dppb) (4,4′-X2-2,2′-bipy)] (X = -H, -NO2, -Me, -COOH, -SMe, -O=SMe, -Cl, -OMe) complexes
Santiago, Marcelo O.,Donicci Filho, Claudio L.,Moreira, Icaro de S.,Carlos, Rose Maria,Queiroz, Salete L.,Batista, Alzir A.
, p. 3205 - 3211 (2008/10/08)
A series of [RuCl2(dppb)(4,4′-X2-2,2′ -bipy)] complexes was synthesized from [RuCl2(dppb)(PPh3) and 4,4′-X2-2,2′-bipy [dppb=1,4-bis(diphenylphosphino)butane and 4,4′-X2-2,2′ -bipy=2,2′-bipyridine (bipy), 4,4′-dimethoxy-2,2′-bipyridine (MeO-bipy), 4,4′-dimethyl-2,2′-bipyridine (Me-bipy), 4,4′-dicarboxy-2,2′-bipyridine (COOH-bipy), 4,4′ -dithiomethyl-2,2′-bipyridine (MeS-bipy), 4,4′-dichloro-2,2′ -bipyridine (Cl-bipy), 4,4′-dinitro-2,2′-bipyridine (NO 2-bipy), and 4,4′-dithiomethylsulphoxide-2, 2′-bipyridine (MeS=O-bipy)]. The complexes were characterized by elemental analysis, cyclic voltammetry and differential pulse voltammetry, and by UV-Vis and 31P{1H}NMR spectroscopies. The pK a of the ligands were determined. The trans-[RuCl 2(dppb)(4,4′-X2-2,2′-bipy) complexes were photoisomerized under white light and the isomerization rate constants from trans to cis isomers were consistent with first order reactions and were correlated with the pKa of the ligands and with the E1/2 of the complexes. The suggested mechanism of isomerization reactions is consistent with an intramolecular twist process.
