Hexanuclear copper(II) cages built on a central {μ3-O⋯H⋯μ 3-O} moiety, 1,3-bis(dimethylamino)-2-propanolato and capping R-phosphonates: Crystal structures, magnetic behavior, and DFT studies

Abstract

The syntheses, structural characterization, and magnetic behavior of two new hexanuclear copper(II) complexes derived from R-phosphonic acids and 1,3-bis(dimethylamino)-2-propanol (Hbdmap) with formulas [Cu 6(μ- bdmap) 3(μ 3-Ph-PO 3) 2(μ 3-O⋯H⋯μ 3-O)(ClO 4) 2(H 2O)]·5H 2O (1) and [Cu 6(μ-bdmap) 3(μ 3-t-Bu-PO 3) 2(μ 3-O⋯H⋯μ 3-O) (μ 1,3-dca)(dca)(H 2O)]·6H 2O (2) (Ph-H 2PO 3 = phenylphosphonic acid, t-Bu-H 2PO 3 = tert-butylphosphonic acid, dca = dicyanamide) are reported. Compounds 1 and 2 are hexanuclear 3.111 R-phosphonate(2-)/1,3- bis(dimethylamino)-2-propanolato(1-) cages including in the center the [μ 3-O⋯H⋯μ 3-O] 3- unit. The temperature dependence of the magnetic properties of 1 and 2 clearly indicates an overall strong antiferromagnetic coupling confirmed by DFT calculations. © 2012 American Chemical Society.