Structure and Solution Behavior of Rare-Earth-Metal Complexes with Tripodal N-Donor Ligands.

We report the synthesis of multiple rare-earth-metal complexes (Ln = Y, La, Ce, Sm, Lu) using tripodal N-donor ligands, which offer the key advantage of featuring only C, H, O and N elements, facilitating incineration to recover the metal. The structural properties of the Ln3+ complexes were investigated by X-ray diffraction, revealing that the ligands form complexes with a 1:1 ligand-to-metal ratio, with two of the three triflate anions coordinated to the metal centers in all cases. The coordination of the third triflate anion was found to be variable, as supported by various NMR spectroscopic investigations. Additionally, transitioning from the previously reported tris(hydrazonyl)thiophosphanyl (SP)-based ligand system to the herein reported tris(2-aminoethyl) amine (tren)-anchored ligand system enhanced flexibility, resulting in improved encapsulation of the lanthanide ions. Competition studies between the two systems revealed selective coordination of the lutetium ion with the more flexible system. Thus, enhancing the flexibility of the ligand systems used for extraction has the potential to increase their efficiency.

Synthesis, Crystal Structures, and Ion Pairing of κ6 N Complexes with Rare-Earth Elements in the Solid State and in Solution.

The rare earth element complexes (Ln=Y, La, Sm, Lu, Ce) of several podant κ6 N-coordinating ligands have been synthetized and thoroughly characterized. The structural properties of the complexes have been investigated by X-ray diffraction in the solid state and by advanced NMR methods in solution. To estimate the donor capabilities of the presented ligands, an experimental comparison study has been conducted by cyclic voltammetry as well as absorption experiments using the cerium complexes and by analyzing 89 Y NMR chemical shifts of the different yttrium complexes. In order to obtain a complete and detailed picture, all experiments were corroborated by state-of-the-art quantum chemical calculations. Finally, coordination competition studies have been carried out by means of 1 H and 31 P NMR spectroscopy to investigate the correlation with donor properties and selectivity.

Catalytic Performance and Electrophoretic Behavior of an Yttrium-Organic Framework Based on a Tricarboxylic Asymmetric Alkyne.

A new Y-based metal-organic framework (MOF) GR-MOF-6 with a chemical formula of {[YL(DMF)2]·(DMF)}n {H3L = 5-[(4-carboxyphenyl)ethynyl] isophthalic acid; DMF = N,N-dimethylformamide} has been prepared by a solvothermal route. Structural characterization reveals that this novel material is a three-dimensional MOF in which the coordination of the tritopic ligand to Y(III) metal ions leads to an intercrossing channel system extending over three dimensions. This material has proven to be a very efficient catalyst in the cyanosilylation of carbonyls, ranking second in catalytic activity among the reported rare earth metal-based MOFs described so far but with the lowest required catalyst loading. In addition, its electrophoretic behavior has been studied in depth, providing a zero-charge point between pH 4 and 5, a peak electrophoretic mobility of -1.553 µm cm V-1 s-1, and a ζ potential of -19.8 mV at pH 10.

Synthesis of Cannabinoids: "In Water" and "On Water" Approaches: Influence of SDS Micelles.

We have proven that the biomimetic-like synthesis of cannabinoids from citral and the corresponding phenolic counterpart may well be carried out using water as a solvent. The influence of different additives such as surfactants was also analyzed. Rationalization of the reaction mode and regiochemistry of the processes were provided in terms of "on water" and "in water" reactions. The same reactions were conducted in organic media using Ga(III) salts as catalysts. Worthy of being underlined, an unprecedented formal [2+2+2] process was found to occur between two citral molecules and the corresponding phenolic species in both aqueous and organic environments. Computational studies were performed in order to gain a comprehensive mechanistic and energetic understanding of the different steps of this singular process. Finally, the influence of SDS micelles in the chemical behavior of olivetol and citral was also pursued using PGSE diffusion and NOESY NMR studies. These data permitted to tentatively propose the existence of a mixed micelle between olivetol and SDS assemblies.

Intranasal bevacizumab treatment on epistaxis in hereditary haemorrhagic telangiectasia: a case report.

Hereditary haemorrhagic telangiectasia (HHT), also known as Osler-Weber-Rendu disease, is a rare, vascular, autosomal dominant disorder. The purpose of this paper is to describe the efficacy and safety of treatment with intranasal bevacizumab in HHT. A 42-year-old woman with HHT presented with frequent episodes of epistaxis. Iron studies showed anaemia of iron deficiency from chronic blood loss. Because of the frequent epistaxis (Epistaxis Severity Score (ESS) 6.76) and varying haemoglobin levels (Hb range: 7.7-9.9g/dL) her doctors sought treatment with intranasal bevacizumab. This treatment was prescribed at the hospital pharmacy department in a laminar flow hood. 2.5 mL (25 mg) were placed in a nasal spray bottle. The recommended dosage was twice a day for two consecutive months. Nasal treatment seemed to control her epistaxis, and no adverse effects were reported. She only had a few further minor episodes of epistaxis, which were easily controlled (ESS 3.44). The haemoglobin levels evreached normal levels (Hb range: 12.8-14.1g/dL).