Syntheses, Structures and Magnetic Properties of Heterobridged Dinuclear and Cubane‐Type Tetranuclear Complexes of Nickel(II) Derived from a Schiff Base Ligand

Abstract

Abstract Syntheses, structures and magnetic properties of a heterobridged μ‐phenoxido‐μ 1,1 ‐NCO dinickel(II) compound [Ni II 2 (HL) 3 (μ‐NCO)] · 2H 2 O ( 1 ) and a heterobridged bis(μ 3 ‐phenoxido)bis(μ 3 ‐alkoxido)tetranickel(II) system, [Ni II 4 (L) 2 (HL) 2 (SeCN) 2 (H 2 O) 2 ] · C 3 H 7 NO · 4H 2 O ( 2 ), containing a cubane‐type Ni II 4 O 4 core, derived from the tetradentate Schiff base compartmental ligand N ‐(2‐hydroxyethyl)‐3‐methoxysalicylaldimine (H 2 L) were described. Compounds 1 and 2 crystallize in triclinic P $\bar {1}$ and monoclinic P 2 1 / c systems, respectively. Compound 2 , in which the Ni 4 O 4 cubane core is composed of two μ 3 ‐phenoxido and two μ 3 ‐alkoxido moieties, represents the sole example of this type. The variable‐temperature (2–300 K) magnetic susceptibilities and magnetizations of these two compounds were measured. The interaction between the metal centres in dinuclear compound 1 is weak ferromagnetic, resulting in an S T = 2 ground state at 2 K. The overall interaction observed in 2 is weak ferromagnetic, leading to an unusual S T = 3 ground state. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)