Tricarbonyl Complexes of Rhenium(I) with Acetylpyridine Benzoylhydrazone and Related Ligands

Crystal structure of fac-aqua-[(E)-4-(benzo[d]thia-zol-2-yl)-N-(pyridin-2-yl-methyl-idene)aniline-κ2 N,N']tricarbonylrhenium(I) hexa-fluorido-phosphate methanol monosolvate

In the title compound, fac-[Re(C19H13N3S)(CO)3(H2O)]PF6·CH3OH, the coordination environment of the ReI atom is octa-hedral with a C3N2O coordination set. In this mol-ecule, the N,N' bidentate ligand, (E)-4-(benzo[d]thia-zol-2-yl)-N-(pyridin-2-yl-methyl-idene)aniline, and the monodentate aqua ligand occupy the three available coordination sites of the [Re(CO)3]+ core, generating a '2 + 1' mixed-ligand complex. In this complex, the Re-C bonds of the carbonyl ligands trans to the coordinating N,N' atoms of the bidentate ligand are longer than the Re-C bond of the carbonyl group trans to the aqua ligand, in accordance with the intensity of their trans effects. The complex is positively charged with PF6 - as the counter-ion. In the structure, the complexes form dimers through π-π inter-molecular inter-actions. O-H⋯O and O-H⋯N hydrogen bonds lead to the formation of stacks parallel to the a axis, which further extend into layers parallel to (01). Through O-H⋯F hydrogen bonds between the complexes and the PF6 -counter-anions, a three-dimensional network is established.

Tricarbonylrhenium(i) complexes with 2-acetylpyridine-derived hydrazones are cytotoxic to NCI-H460 human large cell lung cancer

Tricarbonylrhenium(i)-hydrazone complexes showed antiproliferative activity against NCI-H460 cells. The mode of action involves apoptosis and ROS scavenge.

Rhenium(I) compounds bound by tripodal ligands of pyridine and N-methylimidazole

The reaction of Re(CO)(5)Br with tris(2-pyridyl)methanol (tpmOH) leads to unexpectedly complex chemistry with three new compounds forming instead of a single product. In compound 1, the tpmOH ligand binds to the metal in the N,N',N''-mode; 2 has tpmO(-) bound in the N,N',O-mode; while 3 is a dimer with the tpmO(-) ligand utilizing each of the four donor atoms to bridge the two metal centers. The analogous methyl ether ligands, tris(2-pyridyl)methoxymethane (tpmOMe) or tris[2-(l-methylimidazolyl)]methoxymethane (timmOMe), each yielded a single product, 4 and 5, respectively, bound in the N,N',N''-mode, and are new leads for potential radiotherapeutic agents. All compounds have been structurally characterized.

Iron(III) Complexes with a Biologically Relevant Aroylhydrazone: Crystallographic Evidence for Coordination Versatility

Complexation of iron(III) with the heterodonor chelating agent 3,5-di-tert-butylsalicylidene benzoylhydrazine, H2(3,5-tBu2)salbh, in the absence or presence of a base affords the complex cation [Fe{H(3,5-tBu2)salbh}2]+ or the neutral compound [Fe{H(3,5-tBu2)salbh}{(3,5-tBu2)salbh}], respectively, as revealed by single-crystal X-ray analyses. Such a synthetic and crystallographic demonstration of the coordination versatility of an aroylhydrazone toward iron is uncommon. The oxidation and spin states of the iron have been verified with magnetic and spectroscopic measurements.