SYNTHESIS AND COORDINATION CHEMISTRY OF THE HEXADENTATE LIGANDS 1,4,7-TRIS(2-HYDROXYBENZYL)-1,4,7-TRIAZACYCLONONANE (H3L1) AND 1,4,7-TRIS(3-TERT-BUTYL-2-HYDROXYBENZYL)-1,4,7-TRIAZACYCLONONANE (H3L2) - CRYSTAL-STRUCTURES OF [HL1CUII] AND [L2FEIII]ACACH

Two new hexadentate macrocycles containing phenolate pendant arms have been prepared from 1,4,7-triazacyclononane and 3 equiv of 2-(bromomethyl)phenyl acetate: 1,4,7-tris(2-hydroxybenzyl)-1,4,7-triazacyclononane (H3L1; C27H33N3O3) and 1,4,7-tris(3-terf-butyl-2-hydroxybenzyl)-1,4,7-triazacyclononane (H3L2, C39H57N3O3). The reaction of trivalent first-row transition metals with the trianions affords monomeric pseudooctahedral complexes, of which the following have been characterized: L1MnIII; L1FeIII; L2CoIII [L2FeIII]acacH; L2FeIII; L2MnIII. The reaction of copper(II) Perchlorate with the new ligands affords five-coordinate species: HL1CuII; [H2L2CuII]C104 (green), [HL2CuII]NaC104 (red). Co(BF4)2•6H2O reacts with H3L1 in the presence of air to give a trinuclear complex: [(L1CoIII)2CoII](BF4)2•H2O. The crystal structures of [HL1CuII] (1) and [L2FeIII]acacH (2), where acacH is acetylacetone, have been determined by X-ray crystallography: (1) space group P21/n, a = 8.687 (4) Ǻ, b = 13.320 (9) Ǻ, c = 20.789 (8) Ǻ, β = 102.09 (4)°, Z = 4; (2) space group P21/n, a = 12.347 (9) Ǻ, b = 18.929 (9) Ǻ, c = 17.699 (9) Ǻ, β = 92.23 (6)°, Z = 4. In 1 the Cu(II) center is in a square-based-pyramidal environment of three nitrogen donors and two phenolate oxygen atoms whereas the ferric ion in 2 is in a pseudooctahedral environment (N3O3 donor set). Electronic spectral data, magnetic properties, and the electrochemistry of the new complexes are reported. © 1990, American Chemical Society. All rights reserved.