An Oxide-Centered Trinuclear Manganese(III) Compound with a Bulky Phenol-Pyrazolate Ligand

Abstract

A new oxide-centered trinuclear manganese(III) compound with the formula [Mn3(μ3-O)(naphpz)3(O2CMe)(MeOH)2]n (1) {H2naphpz = 2-[1H-pyrazol-5(3)-yl]naphthalen-1-ol} has been synthesized and characterized. Three bulky doubly deprotonated phenol-pyrazole ligands are coordinated to the three manganese(III) ions with a μ3-oxide bridge in the same plane. Methanol and acetate ligands are at the apical positions of the manganese(III) ions. The trinuclear units are bridged by acetate ligands in the anti-anti mode, leading to the formation of 1-D chains. Temperature-dependent magnetic susceptibility studies indicate the presence of overall antiferromagnetic interactions with magnetic exchange constants of J1 ≈ –1.9 and J2 ≈ –5.5 cm–1 and g = 1.91. Weak antiferromagnetic interactions (zJ′ = –0.37 cm–1) between the trinuclear units in the 1-D chain (and between the chains) in compound 1 are present.