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C61H50Cl2Fe2I12N12, orthorhombic, Pbcn (no. 60), a = 13.0247(4) Å, b = 17.0204(5) Å, c = 34.1475(9) Å, β = 90, V = 7570.0(4) Å3, Z = 4, Rgt (F) = 0.0694, wRref (F 2) = 0.1605, T = 293(2) K.

C18H19BF2FeI4N3, triclinic, P1̄ (no. 2), a = 8.2997(3) Å, b = 11.8180(9) Å, c = 14.0849(7) Å, α = 106.388(5)°, β = 101.841(4)°, γ = 95.200(4)°, V = 1280.88(13) Å3, Z = 2, Rgt(F) = 0.0393, wRref(F2) = 0.1045, T = 293(2) K.

C61H50Cl2Fe2I12N12, orthorhombic, Pbcn (no. 60), a = 13.0247(4) Å, b = 17.0204(5) Å, c = 34.1475(9) Å, β = 90, V = 7570.0(4) Å3, Z = 4, Rgt(F) = 0.0694, wRref(F2) = 0.1605, T = 293(2) K. [ABSTRACT FROM AUTHOR]

Six iron(0) tricarbonyl complexes (1a–f) with a η4-1-azadiene moiety were prepared and their performance in the hydroboration of unsaturated organic compounds was investigated. All the complexes exhibit catalytic activity towards hydroboration of ketones, aldehydes and aldimines with pinacolborane (HBpin) as a hydride source to lead to secondary alcohols, primary alcohols, and secondary amines, respectively, after hydrolysis of the hydroboration products. Of the iron(0) tricarbonyl complexes, complex 1e is the most robust one and was employed throughout the catalytic investigation. Its preference towards the three types of substrates is as follows: aldimines > aldehydes ≫; ketones. In total, 24 substrates were examined for the catalytic hydroboration reactivity and generally, isolation yields ranging from 40% to 95% were achieved. Mechanistic investigation suggests that the catalytic hydroboration of the substrates proceeds via intramolecular hydride transfer without going through an Fe–H intermediate. As indicated by 1H NMR spectroscopic monitoring, the substrates and the borane agent bind to the iron centre and the imine N atom, respectively, which facilitates the hydride transfer by activating the B–H bond and polarizing the double bond of the substrates. [ABSTRACT FROM AUTHOR]

ABSTRACT This work reports the preparations and anticancer activities of a set of platinum (II) complexes. Two types of bidentate ligands, azadiphosphine (PNP) and diphosphine (PP), were applied to afford different kinds of platinum centers, the homoleptic complexes, [Pt (PNP)2]2+ (1 and 2) and [Pt (PP)2]2+ (4), and the hybrid complex, [Pt (PNP)(PP)]2+ (3). All these complexes are characterized by various analytical techniques, and their structures were validated using single‐crystal X‐ray diffraction analysis. Notably, the stability of the complexes 1–4 is differentiated both in phosphate‐buffered saline (PBS) and in the culture media (RPMI‐1640), relative to the type of coordinated diphosphine ligands, specifically, the more PNP ligands, the less stability. The bite angles of P‐Pt‐P bonds in 1–4 would be reliant on their stability, so that complexes 1 and 2 with small bite angles tend to be labile. A mechanistic understanding on the decomposition of 2 is proposed with the aid of mass analysis. As a result, their anticancer activities should be also associated with their stability so that the chelated ligands, with more PNP ligands, lead to more cytotoxicity. Mechanistically, the poisonous platinum (II) derivatives of complex 2 should interact with the nucleus DNA, whereas the intact complex 4 is not traceable, confirming from a γ‐H2AX‐related immunofluorescence staining kit. Additionally, complex 2 exhibits severe toxicity toward several cancer cells as well as a normal cell. Furthermore, complex 2 has inhibited the formation and viability of three‐dimensional T24 mammospheres, reminding it of a promising candidate for anticancer treatments. Overall, the present work provides a way for the systematic investigation to elucidate how a bidentate diphosphine ligand modulates the stability and the anticancer activities of the corresponding square‐planner platinum (II) complex. [ABSTRACT FROM AUTHOR]

Four new monoiron (II) tricarbonyl complexes with the amine bound, fac‐[Fe(CO)3I2(NH2R)] (R = Et, 1; nPr, 2; nBu, 3; nPent, 4), were reported using cis‐[Fe(CO)4I2] as the precursor. All the complexes 1–4 were structurally confirmed by various techniques such as ultraviolet–visible (UV–vis), Fourier transform infrared (FTIR), and nuclear magnetic resonance (NMR) spectra and elemental analysis of which complexes 1 and 2 are crystallographically determined. The reaction of the precursor with alkylamines proceeded in two main parallel pathways to form both aminium salts of fac‐[Fe(CO)3I3]− and the amine‐bound complexes (1–4). Their dominances altered with the reaction time. These complexes in DMSO undergo quick decomposition with complex 1 as the relatively most stable one (t1/2 = 7.3 min) although they are stable in solid status. Unlike the triiodo anion and pyridinyl analogs showing severe cytotoxicity due to the generation of iodine radical during the decomposition, no iodine radicals were detected from the fac‐[Fe(CO)3I2(NH2R)] complexes. Therefore, the cell viability of RT112 cells was not affected by the presence of the amine‐bound iron complex (1) up to 100 μmol L−1. [ABSTRACT FROM AUTHOR]

One 18-metal Eu(III) nanoring (size: 1.0 × 2.7 × 2.7 nm) was constructed as a rapid ratiometric fluorescent probe for the detection of dipicolinic acid with high sensitivity and selectivity, by using two types of polydentate organic ligands. [ABSTRACT FROM AUTHOR]

Four iron(II) carbonyl complexes, fac‐[Fe (CO)3X2(py)] (X = I−, 1 and Br−, 3), fac‐[{Fe (CO)3X2}2(bipy)] (X = I−, 2 and Br−, 4), were facilely synthesized by reacting cis‐[Fe (CO)4X2] (X = I−, Br−) with pyridine (py) and 4,4′‐dipyridine (bipy) ligands, respectively, in good yields (70%~85%). These complexes were fully characterized, and the structures of Complexes 2 and 3 were crystallographically analyzed. In dimethyl sulfoxide, they decomposed rapidly to release carbon monoxide (CO), and in methanol, they showed better stability which allowed kinetically analyzing their decomposing behaviors. The self‐decomposing in methanol fitted first‐order kinetics with a half‐time ranging from several minutes to 1 h. Our results suggested that the ligand with great conjugation (bipy) and strong electron‐donating capability (iodide) could stabilize the iron(II) carbonyl complexes. The decomposition of the iodo complexes (1 and 2) involved the production of iodine radicals. MTT (3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyl tetrazolium bromide) assessments revealed that the efficacy against human bladder carcinoma cell line (RT112) is in the following trend: 1 > 2 > 3 > 4. The relatively strong efficacy of Complexes 1 and 2 is mainly contributed to the in situ generated iodine radicals. The combination of the cytotoxicity of the in situ generated radicals with the anticancer activity of CO as reported in literatures may lead to developing novel anticancer drugs with enhanced efficacy. [ABSTRACT FROM AUTHOR]

In this study, five salts containing the same anion fac-[FeII(CO)3I3]− were prepared through the reaction of cis-[Fe(CO)4I2] with organic amines whose protonated forms, i.e., (EtNH3+), (PrNH3+), (BuNH3+), (PentNH3+), and (Et2NH2+), become the cations of the salts 1, 2, 3, 4, and 5, respectively. These aminium salts, which are soluble in water and polar organic solvents such as DMSO and methanol, were characterized by various techniques including X-ray single-crystal diffraction. These salts underwent solvolysis in both water and DMSO to release CO, following first-order kinetics. In DMSO, the decomposition of these salts proceeded via a significantly simpler mechanism without the involvement of radicals than that in water, and the CO-release rate of these salts was almost linearly related to the hydrophobicity (the logarithm of the oil/water partition coefficient P) of the amines. The CO-release rate was substantially faster in water and in addition to undergoing solvolysis, the anions generated an iodine radical, I˙. Due to the complicated decomposition of these salts in water, the CO-release proceeded in a two-stage manner. The iodine radical was found to be at least partly responsible for the cytotoxicity of these salts in water; this indicates that the proposed anion has potential for applications in cancer therapy. [ABSTRACT FROM AUTHOR]