Synthesis and Characterization of Ruthenium Complexes Having Tridentate N-Ethyl-N,N-bis(2-pyridylmethyl)amine Coordinating in a Facial or Meridional Fashion

Ruthenium complexes containing a tridentate N-ethyl-N,N-bis(2-pyridylmethyl)amine (N,N-bis(2-pyridylmethyl)ethylamine: bpea) ligand having two different types of nitrogen donors, one an amine and the other pyridine rings connected with flexible CH2-arms, were synthesized and characterized. A trichlororuthenium isomeric pair of fac- and mer-[RuCl3(bpea)] was synthesized from RuCl3·nH2O in a H2O–C2H5OH solution. A reaction of fac-[RuCl3(bpea)] in an C2H5OH–H2O–CH3CN solution under refluxing conditions afforded a triacetonitrile complex, fac-[Ru(CH3CN)3(bpea)](PF6)2. Four nitrosylruthenium complexes, trans(NO, py), cis(NO, Cl), fac-[RuCl2(NO)(bpea)]PF6, trans(NO, OH), cis(NO, NO2), mer-[Ru(NO2)(OH)(NO)(bpea)]PF6, trans(NO, OCH3), cis(NO, Cl), mer-[RuCl(OCH3)(NO)(bpea)]PF6 and trans(NO, OH), cis(NO, Cl), mer-[RuCl(OH)(NO)(bpea)]PF6, were synthesized and characterized by X-ray crystallography. The bpea of three nitrosylruthenium complexes bearing an electron-donating ligand such as hydroxo or methoxo as an ancillary ligand coordinated in a meridional fashion.