Synthesis, crystal structure, and magnetic properties of a salt containing [Cu 2Cl 7] 3- and 4-nitrobenzyl-49- dimethylaminopyridinium

A new salt, [NO(2)BzDMAP](3)[Cu2Cl7] center dot H2O (1), has been synthesized, where [NO(2)BzDMAP](+) is 1-(4'-nitrobenzyl)-4-dimethylaminopyridinium. Herein, the synthesis, spectral and structural characterization, and magnetic behavior of 1 are reported. It is orthorhombic, with space group Pca2(1), and a = 26.639(2) angstrom, b = 9.638(1) angstrom, and c = 20.011(2) angstrom with V = 5137.5(7) angstrom(3) for Z = 4. The anion shows a chloride-bridged binuclear structure with Cu center dot center dot center dot Cu distance of 3.872 angstrom; the two Cu(II) ions have a tetrahedral geometry. The cations stack through p center dot center dot center dot pi and pi center dot center dot center dot pi interactions, and a complicated hydrogen-bonding network structure is formed through C-H center dot center dot center dot Cl and C-H center dot center dot center dot O hydrogen bonds. The variable temperature magnetic susceptibility measurements reveal that 1 exhibits strong antiferromagnetic interaction with J = -193.0 cm(-1).