Mononuclear anionic octahedral cobalt(III) complexes based on N-salicylidene-o-aminophenol and its derivatives: synthetic, structural and spectroscopic studies.

The reactions of Co(II) sources with N-salicylidene-o-aminophenol (H2saph), N-salicylidene-o-amino-4-methylphenol (H2saph-4Me) and N-salicylidene-o-amino-4-chlorophenol (H2saph-4Cl) were studied in MeOH. The new solid complexes (Bu4(n)N)[Co(III)(saph)2] (1), (Et3NH)[Co(III)(saph-4Me)2]⋅MeOH⋅MeCO2H (2⋅MeOH⋅MeCO2H) and (Et3NH)[Co(III)(saph-4Cl)2]⋅MeOH⋅MeCO2H (3⋅MeOH⋅MeCO2H) have been isolated and their structures determined by single-crystal, X-ray crystallography. The three compounds contain the mononuclear, low- spin octahedral anion [Co(III)L2](-) (H2L=H2saph, H2saph-4Me, H2saph-4Cl), in which both L(2)(-) ligands act as tridentate chelating, meridional ONO donors.

Slow magnetization relaxation in unprecedented Mn(III)4Dy(III)3 and Mn(III)4Dy(III)5 clusters from the use of N-salicylidene-o-aminophenol.

The first use of N-salicylidene-o-aminophenol in 3d/4f chemistry has led to Mn(III)(4)Dy(III)(5) and Mn(III)(4)Dy(III)(3) clusters with unprecedented metal topologies and stoichiometries; both compounds exhibit out-of-phase signals indicative of the slow magnetization relaxation of a single-molecule magnet.

Synthesis, Structure, and Antiproliferative Activity of Three Gallium(III) Azole Complexes.

As part of our interest into the bioinorganic chemistry of gallium, gallium(III) complexes of the azole ligands 2,1,3-benzothiadiazole (btd), 1,2,3-benzotriazole (btaH), and 1-methyl-4,5-diphenylimidazole (L) have been isolated. Reaction of btaH or btd with GaBr(3) or GaCl(3) resulted in the mononuclear complexes [GaBr(3)(btaH)(2)] (1) and [GaCl(3)(btd)(2)] (2), respectively, while treatment of GaCl(3) with L resulted in the anionic complex (LH)(2)[GaCl(4)] (3). All three complexes were characterized by single-crystal X-ray crystallography and IR spectroscopy, while their antiproliferative activities were investigated against a series of human and mouse cancer cell lines.

Methanolysis as a route to gallium(III) clusters: synthesis and structural characterization of a decanuclear molecular wheel.

Treatment of a methanolic solution of gallium(III) nitrate with lithium hydroxide in the presence of benzilic acid resulted in the decanuclear cluster [Ga(OMe)2{O2CC(OH)Ph2}]10 (1). The metal and the organic components have assembled to form a cyclic molecule that adopts the structure of a wheel. The 10 Ga(III) ions are approximately coplanar and are coordinated in a distorted octahedral manner by six oxygen atoms.

Synthetic analogue approach to metallobleomycins: syntheses, structure and properties of mononuclear and tetranuclear gallium(III) complexes of a ligand that resembles the metal-binding site of bleomycin.

As part of our interest into the bioinorganic chemistry of gallium, gallium(III) complexes of the peptide ligand N-(2-(4-imidazolyl)ethyl)pyridine-2-carboxamide (pypepH2) resembling a fragment of the metal-binding domain of bleomycins (BLMs), have been isolated. Reaction of pypepH2 with (Et4N)[GaCl4] and Ga(acac)3 [acac- is the acetylacetonate(-1) ion] affords the mononuclear complex [Ga(pypepH)2]Cl.2H2O (1) and the tetranuclear complex [Ga4(acac)4(pypep)4].