Cis-trans isomerization of {RuNO}(6)-type nitrosylruthenium complexes containing 2-pyridinecarboxylate and structural characterization of a mu-H3O2 bridged dinuclear nitrosylruthenium complex

摘要

cis-[Ru(NO)Cl(pyca)(2)] (pyca = 2-pyridinecarboxylate) ([1]), reacts with nucleophiles such as OH- and N-3(-) in H2O to generate the dimeric nitrosylruthenium complex, [{Ru(NO)(pyca)(2)}(2)(mu-H3O2)]PF6.2H(2)O([2]PF6.2H(2)O). The bridging unit of [2]PF6 is a hydroxide hydrate anion (H3O2-) composed of a hydroxo and an aqua moiety. Coordinated to each of the ruthenium centers are two pyca ligands in the trans-form with the pyridyl nitrogen atoms and the carboxylic oxygen atoms being at the trans position to each other (trans-form; trans(N,N), trans(O,O)-configuration). [2]PF6 has also been isolated by the reaction of [1] with N-3(-) in H2O. The reaction of [1] with CH3O- in CH3OH gives the transform nitrosylruthenium complex, trans-[Ru(NO)(OCH3)(pyca)(2)].CH3OH (trans(N,N), trans(O,O)-configuration) ([3].CH3OH). The rare cis- trans isomerizations have thus occurred during the reaction between [1] (cis-form; trans(N,N), cis(O,O)-configuration)and OH-, N-3(-) or CH3O-. [References: 36]