title: New ruthenium(II) complexes with enantiomerically pure bis- and tris(pinene)-fused tridentate ligands. Synthesis, characterization and stereoisomeric analysis.
abstract: A new set of Ru-Cl complexes containing either the pinene[5,6]bpea ligand (L1) or the C3 symmetric pinene[4,5]tpmOMe (L2) tridentate ligand in combination with the bidentate (B) 2,2'-bipyridine (bpy) or 1,2-diphenylphosphinoethane (dppe) with general formula [RuCl(L1 or L2)(B)](+) have been prepared and thoroughly characterized. In the solid state, X-ray diffraction analysis techniques have been used. In solution, cyclic voltammetry (CV) and 1D and 2D NMR spectroscopy have been employed. DFT calculations have been also performed on these complexes and their achiral analogues previously reported in our group, to interpret and complement experimental results. Whereas isomerically pure complexes ([Ru(II)Cl(L2)(bpy)](BF4), 5 and [Ru(II)Cl(L2)(dppe)](BF4), 6) are obtained when starting from the highly symmetric [Ru(III)Cl3(L2)], 2, isomeric mixtures of cis, fac-[Ru(II)Cl(L1)(bpy)](BF4) (3b/3b'), trans,fac- (3a) and up/down,mer- (3c, 3d) isomers are formed when bpy is added to the less symmetric [Ru(III)Cl3(L1)], 1, in contrast to the case of the bulky dppe ligand that, upon coordination to 1, leads to the trans,fac-[Ru(II)Cl(L1)(dppe)](BF4) (4a) complex as a sole isomer due to steric factors.
authors.affiliation: Departament de Química, Institut de Química Computacional, and Serveis Tecnics de Recerca, Universitat de Girona, Campus de Montilivi, E-17071 Girona, Spain.
authors.forename: Xavier
authors.initials: X
authors.lastname: Sala
authors.forename: Albert
authors.initials: A
authors.lastname: Poater
authors.forename: Alexander
authors.initials: A
authors.lastname: von Zelewsky
authors.forename: Teodor
authors.initials: T
authors.lastname: Parella
authors.forename: Xavier
authors.initials: X
authors.lastname: Fontrodona
authors.forename: Isabel
authors.initials: I
authors.lastname: Romero
authors.forename: Miquel
authors.initials: M
authors.lastname: Solà
authors.forename: Montserrat
authors.initials: M
authors.lastname: Rodríguez
authors.forename: Antoni
authors.initials: A
authors.lastname: Llobet