THE MONONUCLEAR BARIUM AND DINUCLEAR COPPER(II) COMPLEXES OF A 24-MEMBERED BIBRACCHIAL TETRAIMINE SCHIFF-BASE MACROCYCLE DERIVED FROM TRIS(2-AMINOETHYL)AMINE AND 2,5-DIFORMYLFURAN

The synthesis and structure of a mononuclear barium complex BaL(3)(ClO 4)(2) and the synthesis, structure and properties of a mono-mu-hydroxo -bridged dinuclear copper(II) complex of the macrocycle (L(3)) Cu(2)L( 3)(OH)(ClO4)(3) . 1.5H(2)O derived from the cyclocondensation of tris( 2-aminoethyl)amine(tren) and 2,5-diformylfuran(dff) are reported. The barium complex crystallises in the monoclinic space group C2/c and has unit-cell dimensions a = 18.868(5), b = 11.635(2), c = 30.376(6) Angs trom, beta = 95.74(2)degrees with Z = 8. The dinuclear copper(II) comp lex crystallises in the triclinic space group P (1) over bar (C-i(l)) and has unit-cell dimensions a = 10.907(2), b = 14.836(3), c = 22.805( 5) Angstrom, alpha = 85.29(3)degrees beta = 84.70(3)degrees gamma = 85 .44(3)degrees with Z = 4. The copper-copper separation is ca. 3.74 Ang strom and the Cu-OH-Cu angle is ca. 150 degrees. There is a strong ant iferromagnetic interaction between the metals with -2J = 510 cm(-1).