title: Four Ni(II) complexes with the new cyclam-methylimidazole ligand 1-[(1-methyl-1H-imidazol-2-yl)methyl]-1,4,8,11-tetraazacyclotetradecane.
abstract: Although it has not proved possible to crystallize the newly prepared cyclam-methylimidazole ligand 1-[(1-methyl-1H-imidazol-2-yl)methyl]-1,4,8,11-tetraazacyclotetradecane (L(Im1)), the trans and cis isomers of an Ni(II) complex, namely trans-aqua{1-[(1-methyl-1H-imidazol-2-yl)methyl]-1,4,8,11-tetraazacyclotetradecane}nickel(II) bis(perchlorate) monohydrate, [Ni(C(15)H(30)N(6))(H(2)O)](ClO(4))(2)·H(2)O, (1), and cis-aqua{1-[(1-methyl-1H-imidazol-2-yl)methyl]-1,4,8,11-tetraazacyclotetradecane}nickel(II) bis(perchlorate), [Ni(C(15)H(30)N(6))(H(2)O)](ClO(4))(2), (2), have been prepared and structurally characterized. At different stages of the crystallization and thermal treatment from which (1) and (2) were obtained, a further two compounds were isolated in crystalline form and their structures also analysed, namely trans-{1-[(1-methyl-1H-imidazol-2-yl)methyl]-1,4,8,11-tetraazacyclotetradecane}(perchlorato)nickel(II) perchlorate, [Ni(ClO(4))(C(15)H(30)N(6))]ClO(4), (3), and cis-{1,8-bis[(1-methyl-1H-imidazol-2-yl)methyl]-1,4,8,11-tetraazacyclotetradecane}nickel(II) bis(perchlorate) 0.24-hydrate, [Ni(C(20)H(36)N(6))](ClO(4))(2)·0.24H(2)O, (4); the 1,8-bis[(1-methyl-1H-imidazol-2-yl)methyl]-1,4,8,11-tetraazacyclotetradecane ligand is a minor side product, probably formed in trace amounts in the synthesis of L(Im1). The configurations of the cyclam macrocycles in the complexes have been analysed and the structures are compared with analogues from the literature.
authors.affiliation: INQUIMAE, Departamento de Química Inorgánica, Analítica y Química Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina.
authors.forename: Ariel G
authors.initials: AG
authors.lastname: De Candia
authors.forename: Matias
authors.initials: M
authors.lastname: Molnar
authors.forename: Leonardo D
authors.initials: LD
authors.lastname: Slep
authors.forename: Ricardo
authors.initials: R
authors.lastname: Baggio
mesh_terms: D056831:Coordination Complexes / Q000737:chemistry*; D018360:Crystallography, X-Ray; D006571:Heterocyclic Compounds / Q000737:chemistry*; D006860:Hydrogen Bonding; D008024:Ligands; D008958:Models, Molecular; D015394:Molecular Structure; D009532:Nickel / Q000737:chemistry*; D009942:Organometallic Compounds / Q000737:chemistry*
chemical_list: D056831:Coordination Complexes; D006571:Heterocyclic Compounds; D008024:Ligands; C573416:Ni(II)-1-((1-methyl-1H-imidazol-2-yl)methyl)-1,4,8,11-tetraazacyclotetradecane; D009942:Organometallic Compounds; C024560:cyclam; D009532:Nickel