A convenient synthetic route to the monocondensation products of pentane-2,4-dione and aliphatic α,ω-diamines. Synthesis, x-ray structure and magnetic properties of a trinuclear copper(II) complex with 8-amino-5-aza-4-methyl-3-octene-2-one

Abstract

A convenient synthesis of four, new, tridentate-N 2O ligands which are monocondensation products of pentane-2,4-dione and aliphatic α,ω-diamines is described, and the basic properties of these ligands are reported. The reaction of one of them, 8-amino-5-aza-4-methyl-3-octene-2-one, HL 1, with copper(II) perchlorate affords the trinuclear μ 3-hydroxo bridged complex [(CuL 1) 3(OH)](ClO 4) 2. The single-crystal X-ray structure, spectroscopic and magnetic properties of this complex are described. The trinuclear cation consists of three CuL 1 subunits bound by a triply-bridging hydroxy group and three bridges formed by carbonyl oxygen atoms of three ligand molecules. Two trinuclear cations are held together within the unit cell by hydrogen bonding to the perchlorate anions. Crystallographic data: triclinic space group P 1 (No. 2), a = 11.720(1), b = 12.283(2), c = 14.252(2) Å; α = 71.78(1)°, β = 81.07(1)°, γ = 65.69(1)°, final R and R w factors are 0.0418 and 0.0536 respectively. Magnetic susceptibility data indicate a weak antiferromagnetic exchange within the trinuclear core with J = −15 cm −1.