Formation of a dinuclear and a trinuclear Ni(II) complex on slight variation of experimental conditions: Structural analysis and magnetic properties. (10th January 2017)

• Record Type: Journal Article
• Authors: Biswas, Apurba; Drew, Michael G.B.; Gómez-García, Carlos J.; Ghosh, Ashutosh
• Is Part Of: Polyhedron. Volume 121(2017)
• Page Start: 80
• Page End: 87
• Publication Date: 2017-01-10
• Subjects: Nickel(II) -- Reduced Schiff base -- Nitrite -- Crystal structure -- Magnetic properties; Chemistry, Inorganic -- Periodicals; Chimie inorganique -- Périodiques; Organometaalverbindingen; Anorganische chemie; 546.05
• DOI: 10.1016/j.poly.2016.09.050
• Languages: English
• ISSNs: 0277-5387

Abstract

Graphical abstract: A diphenoxido bridged antiferromagnetically coupled dinuclear Ni(II) complex [Ni2 L2 (NO2 )2 ] (1 ) and a μ2 and μ3 -phenoxido, μ3 -hydroxido, and μ2 -nitrito (1κ O :2κ N ) bridged ferromagnetically coupled trinuclear Ni(II) complex [Ni3 L3 (OH)(NO2 )]·ClO4 (2 ), have been synthesized using a tridentate reduced Schiff base ligand and varying the reaction conditions. Abstract: A diphenoxido bridged dinuclear Ni(II) complex [Ni2 L2 (NO2 )2 ] (1 ) and a μ2 and μ3 -phenoxido, μ3 -hydroxido, and μ2 -nitrito (1κ O :2κ N ) bridged trinuclear Ni(II) complex [Ni3 L3 (OH)(NO2 )]·ClO4 (2 ), have been synthesized using a tridentate reduced Schiff base ligand HL (HL = 2-[(2-dimethylamino-ethylamino)-methyl]-phenol). Both complexes were characterized by X-ray structure determination and variable-temperature magnetic susceptibility measurements. In both complexes the nickel atoms are six-coordinated with a distorted octahedral environment. The interesting feature of the trimeric complex2 is that the three mononuclear units are assembled around a μ3 -hydroxido ion in such a way that the three phenoxido groups and one nitrito group form a cyclic bridge that markedly modify the magnetic properties. Complex1 presents a moderate antiferromagnetic Ni–Ni coupling ( J = −39 cm −1 ) through the phenoxido bridges with a wide Ni–O–Ni bond angle of 101.77(6)° whereas the lower Ni–O–Ni bond angles, in the range 86.66(6)–96.07(7)°, lead to a moderate ferromagnetic coupling ( J = +18.2 cm −1 ) in the trimeric complex2 with a weak antiferromagnetic contribution ( J ′ = −0.51 cm −1 ) via the 1κ O :2κ N nitrito bridge.