The stability of phosphorene is shown to be degraded by water. However, the presence of a small amount of water allows the synthesis of high‐quality material in liquid exfoliation of black phosphorus using dimethylsulfoxide as solvent. A phosphorus/water molar ratio between 1.5 and 14 maximizes the quality of the phosphorene flakes and their stability.

The new water-soluble ruthenium(II) chiral complexes [RuCpX(L)(L')](n+) (X = Cl, I. L = PPh3; L' = PTA, mPTA; L = L' = PTA, mPTA) (PTA = 1,3,5-triaza-7-phosphaadamantane; mPTA = N-methyl-1,3,5-triaza-7-phosphaadamantane) have been synthesized and characterized by NMR and IR spectroscopy and elemental analysis. The salt mPTA(OSO2CF3) was also prepared and fully characterized by spectroscopic techniques. X-ray crystal structures of [RuClCp(PPh3)(PTA)] (2), [RuCpI(PPh3)(PTA)] (3), and [RuCpI(mPTA)(PPh3)](OSO2CF3) (9) have been determined. The binding properties toward DNA of the new hydrosoluble complexes have been studied using the mobility shift assay. The ruthenium chloride complexes interact with DNA depending on the hydrosoluble phosphine bonded to the metal, while the corresponding compounds with iodide, [RuCpI(PTA)2] (1), [RuCpI(PPh3)(PTA)] (3), [RuCpI(mPTA)2](OSO2CF3)2 (6), and [RuCpI(mPTA)(PPh3)](OSO2CF3) (9), do not bind to DNA.

One of the latest trends in supramolecular chemistry is the quest for reproducible methods to achieve controlled selforganization of discrete units to form homo-and heterometallic coordination networks, aggregates, and polymers.[1] This development is based on the use of appropriate organic, inorganic, and organometallic building blocks that allow the synthesis of 1D linear or twisted chains, 2D squares and polygons, and 3D cubes and polyhedra.[2] Among the organic spacers, nitrogen-based aromatic heterocycles are the most widely used due to their good donor properties and rigidity. These ligands can act as corner units (bipy, phen) [3] and spacers (pyrazines, [4] terpy, [5] porphyrinates, [6] tetraazamacrocycles [7] ). P-donor ligands as spacers have received less attention:[8] P 2 and P 5 ligands have been studied by Scheer and co-workers, [9] whereas the use of multidentate phosphanes has been reviewed recently.[10] To the best of our knowledge, the use of mixed N,P ligands as metal-coordinating spacers has not been reported to date.Very few coordination polymers are water soluble, an example being the poly(ferrocenylsilane)-b-poly(aminomethacrylate) copolymer recently described by Manners and coworkers [11] as part of their ongoing study on metallocenebased polymers, [12] which can be prepared by ring-opening polymerization to afford either macromolecules with pendant ferrocenyl substituents in the polymer side chains [13] or poly(ferrocenylsilane)s. [14] Other examples of ligands that afford coordination polymers with various topologies and applications are ferrocenyl ligands bearing bipyridines [15] or carboxylates.[16]Herein we describe the first known case of a watersoluble, air-stable, heterobimetallic polymeric structure based on two metal-containing moieties ([CpRu] + and [AgCl 2 ] À ) bridged by a cagelike, water-soluble monodentate phosphane, 1,3,5-triaza-7-phosphaadamantane (pta), in an unprecedented N,P coordinating mode.We recently reported the synthesis and characterization of the water-soluble cyclopentadienylruthenium complex [CpRuCl(pta) 2 ] (1), which is stabilized by the phosphaadamantane-like pta ligand, and described its catalytic and biological properties.[17] As part of our studies on new water-soluble organometallic derivatives based on the [CpRu(pta) 2 ] + moiety, [18] we treated 1 with one equivalent of AgOTf (OTf = OSO 2 CF 3 ) in DMSO to remove the chloro ligand. Unexpectedly, no AgCl precipitated from the resulting orange solution, and neither did it contain the expected product [CpRu(OTf)(pta) 2 ] (2), which was obtained by treatment of 1 with TlOTf. [19] Intrigued by this apparently odd result, we repeated the experiment in an NMR tube.31 P{ 1 H} NMR analysis in [D 6 ]DMSO indicated the formation of a 1:1 mixture of the new complex [CpRu(pta) 2 (dmso-kS)]OTf (3; singlet at d = À28.13 ppm) and the bimetallic neutral coordination polymer [{CpRu(pta) 2 (dmso-kS)}{AgCl 2 }] ¥ (4; singlet at d = À23.19 ppm), as shown in Scheme 1.Quantitative formation of 4 could be attained by ...

Black phosphorus was compressed at room temperature across the A17, A7 and simple‐cubic phases up to 30 GPa, using a diamond anvil cell and He as pressure transmitting medium. Synchrotron X‐ray diffraction showed the persistence of two previously unreported peaks related to the A7 structure in the pressure range of the simple‐cubic phase. The Rietveld refinement of the data demonstrates the occurrence of a two‐step mechanism for the A7 to simple‐cubic phase transition, indicating the existence of an intermediate pseudo simple‐cubic structure. From a chemical point of view this study represents a deep insight on the mechanism of interlayer bond formation during the transformation from the layered A7 to the non‐layered simple‐cubic phase of phosphorus, opening new perspectives for the design, synthesis and stabilization of phosphorene‐based systems. As superconductivity is concerned, a new experimental evidence to explain the anomalous pressure behavior of Tc in phosphorus below 30 GPa is provided.

Black phosphorus (bP) has been recently investigated for next generation nanoelectronic multifunctional devices. However, the intrinsic instability of exfoliated bP (the bP nanoflakes) toward both moisture and air has so far overshadowed its practical implementation. In order to contribute to fill this gap, we report here the preparation of new hybrid polymer-based materials where bP nanoflakes (bPn) exhibit a significantly improved stability. The new materials have been prepared by different synthetic paths including: (i) the mixing of conventionally liquid-phase exfoliated bP (in dimethyl sulfoxide, DMSO) with poly(methyl methacrylate) (PMMA) solution; (ii) the direct exfoliation of bP in a polymeric solution; (iii) the in situ radical polymerization after exfoliating bP in the liquid monomer (methyl methacrylate, MMA). This last methodology concerns the preparation of stable suspensions of bPn–MMA by sonication-assisted liquid-phase exfoliation (LPE) of bP in the presence of MMA followed by radical polymerization. The hybrids characteristics have been compared in order to evaluate the bP dispersion and the effectiveness of the bPn interfacial interactions with polymer chains aimed at their long-term environmental stabilization. The passivation of the bPn is particularly effective when the hybrid material is prepared by in situ polymerization. By using this synthetic methodology, the nanoflakes, even if with a gradient of dispersion (size of aggregates), preserve their chemical structure from oxidation (as proved by both Raman and 31P-solid state NMR studies) and are particularly stable to air and UV light exposure. The feasibility of this approach, capable of efficiently exfoliating bP while protecting the bPn, has been then verified by using different vinyl monomers (styrene and N-vinylpyrrolidone), thus obtaining hybrids where the nanoflakes are embedded in polymer matrices with a variety of intriguing thermal, mechanical, and solubility characteristics.

A new water soluble complex [RuCp(HO-κO)(PTA)] (1) (PTA = 1,3,5-triaza-7-phosphaadamantane) has been synthesized and fully characterized by NMR and IR. The crystal structure of 1(CFSO)·3.5HO was characterized by single crystal X-ray determination. The catalytic activity of this complex was evaluated for the isomerisation of linear allylic alcohols from 3-buten-2-ol to 1-octen-3-ol into the correspondent ketones under both an inert atmosphere and in air, using as solvents: water, the substrate, mixtures of water/substrate, MeOH and mixtures of MeOH/water. An isomerization experiment on a mixture of all the studied allylic alcohols was also carried out.

Nickel nanoparticles were dispersed on the surface of exfoliated black phosphorus and the resulting nanohybrid Ni/2DBP showed an improved stability with respect to pristine 2D BP when kept under ambient conditions in the dark. Ni/2DBP was applied as a catalyst in the semihydrogenation of phenylacetylene and exhibited high conversion and selectivity towards styrene. These features were preserved after recycling tests revealing the high stability of the nanohybrid.

The burgeoning interest in two-dimensional (2D) black phosphorus (bP) contributes to the expansion of its applications in numerous fields. In the present study, 2D bP is used as a support for homogeneously dispersed palladium nanoparticles directly grown on it by a wet chemical process. Electron energy loss spectroscopy–scanning transmission electron microscopy analysis evidences a strong interaction between palladium and P atoms of the bP nanosheets. A quantitative evaluation of this interaction comes from the X-ray absorption spectroscopy measurements that show a very short Pd–P distance of 2.26 Å, proving for the first time the existence of an unprecedented Pd–P coordination bond of a covalent nature. Additionally, the average Pd–P coordination number of about 1.7 reveals that bP acts as a polydentate phosphine ligand toward the surface of the Pd atoms of the nanoparticles, thus preventing their agglomeration and inferring with structural stability. These unique properties result in a superior performance in the catalytic hydrogenation of chloronitroarenes to chloroanilines, where a higher chemoselectivity in comparison to other heterogeneous catalyst based on palladium has been observed.