Playing with different metalloligands [NiL] and Hg to [NiL] ratios to tune the nuclearity of Ni(II)–Hg(II) complexes: Formation of di-, tri-, hexa- and nona-nuclear Ni–Hg clusters. (17th February 2015)

• Record Type: Journal Article
• Authors: Das, Lakshmi Kanta; Gómez-García, Carlos J.; Drew, Michael G.B.; Ghosh, Ashutosh
• Is Part Of: Polyhedron. Volume 87(2015)
• Page Start: 311
• Page End: 320
• Publication Date: 2015-02-17
• Subjects: Nickel(II) -- Mercury(II) -- Hetero-metallic complexes -- Crystal structure -- Ferromagnetic interaction; Chemistry, Inorganic -- Periodicals; Chimie inorganique -- Périodiques; Organometaalverbindingen; Anorganische chemie; 546.05
• DOI: 10.1016/j.poly.2014.11.025
• Languages: English
• ISSNs: 0277-5387

Abstract

Graphical abstract: Five new Ni(II)–Hg(II) hetero-metallic complexes of various nuclearities with salen type Schiff bases have been synthesized by changing metalloligands, the reactant ratios and the counter anions. Abstract: Five new hetero-metallic nickel(II)–mercury(II) complexes, [(NiL 1 )HgCl2 ] (1 ), [(NiL 1 )2 HgCl2 ] (3 ), [(NiL 1 )2 Hg(N3 )2 ] (4 ), [{(NiL 2 )2 Hg(N3 )(μ1, 1 -N3 )}2 ] (5 ) and [{(NiL 2 )2 Hg(N3 )(μ1, 1 -N3 )HgCl2 }2 {Hg(N3 )(μ1, 1 -N3 )}] (6 ) have been synthesized by reacting metalloligands [NiL 1 ] or [NiL 2 ] (where H2 L 1 is N, N′-bis(salicylidene)-1, 2-ethylenediamine and H2 L 2 is N, N′-bis(salicylidene)-1, 3-propanediamine) with HgX2 (X − = Cl − or N3 − ) at different molar ratios. All five complexes have been characterised by X-ray single-crystal structural, elemental and spectroscopic analyses. In complex1, the Hg(II) ion is coordinated to two phenoxido oxygen atoms of one [NiL 1 ] moiety and two terminal chloride ions to form a NiHg dinuclear complex. In the trinuclear complexes3 and4, the central Hg(II) ion is coordinated by two terminal [NiL 1 ] units through two phenoxido oxygens from each and two terminal chloride (in3 ) or azide (in4 ) ions. The centrosymmetric hexanuclear complex5 consists of two trinuclear [(NiL 2 )2 Hg(N3 )(μ1, 1 -N3 )] units, where the phenoxido bridges connect two terminal Ni(II) atoms of the trinuclear units. In these trinuclear units, one azido ligand adopts a μl, 1 -briding mode between Hg and Ni whereas the other one is terminal. In the nonanuclear complex6, two tetranuclear [{(NiL 2 )2 Hg(N3 )(μ1, 1 -N3 )}HgCl2 ] units are linked to a central Hg(II) positioned on a two fold axis, via chlorido, azido, and phenoxido bridges. The tetranuclear unit is formed by the addition of a HgCl2 molecule to a trinuclear [(NiL 2 )2 Hg(N3 )(μ1, 1 -N3 )] unit, similar to that present in5 . Complex5 shows weak ferromagnetic interactions ( J = +2.1 cm −1 ) between the two octahedral Ni(II) ions through double phenoxido bridges with a Ni–O–Ni bond angle of 95.87(11)°.