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The synthesis of the previously‐reported atomically‐precise [Rh16Au6(CO)36]6− (1) nanocluster has been optimized by screening different reaction variables like solvent, stoichiometric ratio, counterion and atmosphere. Its multivalence properties have also been studied by means of electrochemical and spectroelectrochemical techniques; the results pointed out a remarkable electron‐sponge behaviour, as under such experimental conditions 1 is capable to release one electron and accept up to four more, while retaining its molecular structure. This scarce structural variation has been confirmed through DFT calculations on those species whose redox processes showed the maximum reversibility, namely [Rh16Au6(CO)36]7− and [Rh16Au6(CO)36]5−. Moreover, we report herein the isolation and characterization of the new [Rh10Au(CO)26]3− (2) nanocluster, which represents one of the major fallouts of the synthetic pathway investigation of 1. Finally, we disclosed the existence of further species that, from preliminary results, appear to be new large atomically‐precise Rh−Au nanoclusters, which will be the subject of future investigations. Cluster 2 has been identified via single‐crystal X‐ray diffraction analysis, and the characterization of both clusters 1 and 2 completed by infrared (IR) spectroscopy and Electrospray Ionization Mass Spectrometry (ESI‐MS). [ABSTRACT FROM AUTHOR]

The synthesis of the previously‐reported atomically‐precise [Rh16Au6(CO)36]6− (1) nanocluster has been optimized by screening different reaction variables like solvent, stoichiometric ratio, counterion and atmosphere. Its multivalence properties have also been studied by means of electrochemical and spectroelectrochemical techniques; the results pointed out a remarkable electron‐sponge behaviour, as under such experimental conditions 1 is capable to release one electron and accept up to four more, while retaining its molecular structure. This scarce structural variation has been confirmed through DFT calculations on those species whose redox processes showed the maximum reversibility, namely [Rh16Au6(CO)36]7− and [Rh16Au6(CO)36]5−. Moreover, we report herein the isolation and characterization of the new [Rh10Au(CO)26]3− (2) nanocluster, which represents one of the major fallouts of the synthetic pathway investigation of 1. Finally, we disclosed the existence of further species that, from preliminary results, appear to be new large atomically‐precise Rh−Au nanoclusters, which will be the subject of future investigations. Cluster 2 has been identified via single‐crystal X‐ray diffraction analysis, and the characterization of both clusters 1 and 2 completed by infrared (IR) spectroscopy and Electrospray Ionization Mass Spectrometry (ESI‐MS). [ABSTRACT FROM AUTHOR]

The synthesis of hexagonal NaBiF4 co‐doped with Tb3+ and Eu3+(NaBi0.75−xTb0.25EuxF4; with x=0, 5, 10, 20 and 30) was achieved via a facile and fast precipitation route at 35 °C. Powder X‐ray diffraction (PXRD) and luminescence spectroscopy have been employed to characterize and investigate the materials. The study of luminescence spectroscopy and decay kinetics of the 5D4 excited state of Tb3+ provides the evidence of a Tb3+→Eu3+ energy transfer process. Sodium citrate has been adopted as capping agent to promote a homogeneous dispersion of the materials into water and to protect the inorganic host, which is water sensitive, from direct contact with this molecule. The comparison of luminescence properties between bare and citrate‐capped samples of NaBiF4 co‐doped with Tb3+ and Eu3+ reveals a marked difference in the Tb3+→Eu3+ energy transfer efficiency, which has been tentatively explained on the basis of a different environment surrounding the lanthanide ions in the two families of compounds. [ABSTRACT FROM AUTHOR]

We report the first example of very efficient NIR Circularly Polarized Luminescence (CPL) (around 970 nm) in water, obtained thanks to the combined use of a chiral Yb complex and of poly lactic‐co‐glycolic acid (PLGA) nanoparticles. [YbL(tta)2]CH3COO (L=N, N'‐bis(2‐pyridylmethylidene)‐1,2‐(R,R+S,S) cyclohexanediamine and tta=2‐thenoyltrifluoroacetonate) shows good CPL in organic solvents, because the tta ligands efficiently sensitize Yb NIR luminescence and the readily prepared chiral ligand L endows the complex with the necessary dissymmetry. PLGA nanoparticles incorporate the complex and protect the metal ion from the intrusion of solvent molecules, while ensuring biocompatibility, water solubility and stability to the complex. Hydrophilic NIR‐CPL optical probes can find applications in the field of NIR‐CPL bio‐assays. [ABSTRACT FROM AUTHOR]

The chiral cationic complex [Ru(η1‐OAc)(CO)((R,R)‐Skewphos)(phen)]OAc (2R), isolated from reaction of [Ru(η1‐OAc)(η2‐OAc)(R,R)‐Skewphos)(CO)] (1R) with phen, reacts with NaOPiv and KSAc affording [RuX(CO)((R,R)‐Skewphos)(phen)]Y (X=Y=OPiv 3R; X=SAc, Y=OAc 4R). The corresponding enantiomers 2S‐4S have been obtained from 1S containing (S,S)‐Skewphos. Reaction of 2R and 2S with (S)‐cysteine and NaPF6 at pH=9 gives the diastereoisomers [Ru((S)‐Cys)(CO)(PP)(phen)]PF6 (PP=(R,R)‐Skewphos 2R‐Cys; (S,S)‐Skewphos 2S‐Cys). The DFT energetic profile for 2R with (S)‐cysteine in H2O indicates that aquo and hydroxo species are involved in formation of 2R‐Cys. The stability of the ruthenium complexes in 0.9 % w/v NaCl solution, PBS and complete DMEM medium, as well as their n‐octanol/water partition coefficient (logP), have been evaluated. The chiral complexes show high cytotoxic activity against SW1736, 8505 C, HCT‐116 and A549 cell lines with EC50 values of 2.8–0.04 μM. The (R,R)‐Skewphos derivatives show higher cytotoxicity compared to their enantiomers, 4R (EC50=0.04 μM) being 14 times more cytotoxic than 4S against the anaplastic thyroid cancer 8505 C cell line. [ABSTRACT FROM AUTHOR]

Stabilised sulfur ylides are synthetically appealing compounds, which reactivity under Brønsted acid catalysis has been poorly explored. Herein, we report a new catalyst‐ and substrate‐ dependent chemodivergent reaction between stabilised sulfur ylides and salicylaldehydes, leading to the (suprising) formation of 2H‐chromenes or dihydrobenzofurans products. Particular attention was set on the unusual mechanisms involved. Two unique reaction routes including two ylide units in the reactions are proposed. These pathways were validated by performing a selectivity switch in some cases, enabled by the modulation of the nucleophilicity of the sulfur ylide, and by the loading of the Brønsted acid catalyst in the reaction. [ABSTRACT FROM AUTHOR]

This study aimed at surveying lower secondary schools in southern Italy, in a highly polluted area. A community close to an industrial area and three villages in rural areas was investigated. Indoor temperature, relative humidity (RH), gaseous pollutants (CO2 and NO2), selected biological pollutants in indoor dust, and the indoor/outdoor mass concentration and elemental composition of PM2.5 were ascertained. Temperature and RH were within, or close to, the comfort range, while CO2 frequently exceeded the threshold of 1000 ppm, indicating inadequate air exchange rate. In all the classrooms, median NO2 levels were above the WHO threshold value. Dermatophagoides p. allergen concentration was below the sensitizing threshold, while high endotoxin levels were detected in the classrooms, suggesting schools may produce significant risks of endotoxin exposure. Concentration and solubility of PM2.5 elements were used to identify the sources of indoor particles. Indoor concentration of most elements was higher than outdoors. Resuspension was responsible for the indoor increase in soil components. For elements from industrial emission (Cd, Co, Ni, Pb, Sb, Tl, V), the indoor concentration depended on penetration from the outside. For these elements, differences in rural vs industrial concentrations were found, suggesting industrial sources may influence indoor air quality nearby schools. [ABSTRACT FROM AUTHOR]

In this microreview, the authors summarize the reactions of [Pt3n(CO)6n]2– (n = 1–10) Chini clusters aimed at their functionalization, modification and transformation. The results are organized on the basis of the fact that the final products do or do not retain the structure of the parent Chini clusters. The first category comprises the redox reactions of homoleptic Chini clusters, CO/phosphine substitution affording heteroleptic Chini‐type clusters and the formation of Lewis acid‐base adducts by capping the external Pt3‐triangular faces with Lewis acids. The second category consists of globular molecular platinum nanoclusters (platinum browns) obtained by thermal decomposition of Chini clusters, as well as surface decorated platinum carbonyl clusters, composed of a low valent Pt‐CO core decorated by cationic metal fragments. The relevance of such species to molecular cluster chemistry and metal nanoclusters is outlined. [ABSTRACT FROM AUTHOR]

Background Indoor allergens are risk factors for asthma: Thus, the characterization of indoor air quality is important for studying environment-health relationships in children. In particular, Dermatophagoides pteronyssinus is the dominant allergen for asthma. We cross-sectionally investigated the relationships among respiratory symptoms and function, airway inflammation, allergen sensitization, and indoor allergen concentration. Methods One hundred and thirty-two children aging 10-14 years and living in a Southern Mediterranean area were evaluated by parental questionnaires. Spirometry, exhaled nitric oxide (Fe NO), skin prick tests, total, and specific serum IgE analyses were performed along with the evaluation of home dust samples for the content in Der p 1 allergen. Three clusters were created on the basis of the presence/absence of wheeze in the last 12 months (Wh12m) and Der p 1-specific IgE level. Results Cluster 1 (Wh12m+/high Der p 1 IgE) presented higher Fe NO and poorer pulmonary function (lower FEV1 and FEF25%-75%), while its symptom score was not different from Cluster 2 (Wh12m+/low Der p 1 IgE). Cluster 3 (Wh12m−/low IgE) showed the lowest Fe NO values and pulmonary function similar to Cluster 2. Within Cluster 1, both Der p 1-specific IgE and Fe NO were positively correlated with dust Der p 1. Conclusions Similar asthma phenotypes may occur in children despite differences in their atopic state. In atopic children, sensitizing allergens in the indoor environment may increase airway inflammation worsening pulmonary function. Moreover, environmental exposures may contribute to the development of asthma-like symptoms also in the absence of atopic sensitization, thus contributing to asthma overdiagnosis. [ABSTRACT FROM AUTHOR]