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Room-temperature non-aqueous sodium metal batteries are viable candidates for cost-effective and safe electrochemical energy storage. However, they show low specific energy and poor cycle life as the use of conventional organic-based non-aqueous electrolyte solutions enables the formation of interphases that cannot prevent degradations at the positive and negative electrodes. Here, to promote the formation of inorganic NaF-rich interphases on both negative and positive electrodes, we propose the salt-in-presalt (SIPS) electrolyte formulation strategy. In SIPS, sodium bis(fluorosulfonyl)imide (NaFSI) salt is dissolved in the liquid precursor of the sodium bis(trifluoromethylsulfonyl)imide (NaTFSI) salt, that is, N,N-dimethyltrifluoromethane-sulfonamide, called PreTFSI. The prepared 0.5 M NaFSI in PreTFSI (SIPS5) electrolyte solution shows an electrochemical stability up to 6.7 V versus Na|Na+and enables a Na stripping/plating average Coulombic efficiency of 99.7% at 2.0 mA cm−2and 4.0 mAh cm−2in Na||Al cell configuration. By testing SIPS5 in Na metal and ‘anode-less’ coin and pouch cell configurations using NaNi0.6Mn0.2Co0.2O2or sulfurized polyacrylonitrile as positive electrode active materials, we demonstrate the ability of the SIPS strategy to deliver improved specific discharge capacity and capacity retentions at high cell potentials and moderate applied specific currents for cell cycle life up to 1,000 cycles.

The metal–amine complex Co(en)3, where en = ethylenediamine, intercalates between layers of cobalt sulfide (CoS) to form a polar, ferromagnetic metal. We solve the structure of the hybrid compound [Co(en)3](CoS)12·en in the polar group Pca21with lattice parameters a= 14.778(3) Å, b= 11.066(3) Å, and c= 20.095(5) Å using single-crystal X-ray diffraction. The [Co(en)3]2+complexes order between CoS layers and break their inherent fourfold symmetry. Moreover, the chiral Co(en)3complexes hydrogen bond to the terminal sulfides of the layers and break inversion symmetry, thereby inducing a polar state. The shortest hydrogen bond of the amino group is H···S = 2.41(1) Å. From 1.8 to 300 K, the title compound displays metallic electrical resistivity and an anomaly at 43 K. Through magnetization measurements, we find that Co(en)3exhibits spontaneous ferromagnetic order below 43 K. First-principles calculations reproduce the ferromagnetic structure and illustrate decoupling between the conducting electrons and the inversion-lifting distortion. Our work shows that hybrid materials created from intercalation chemistry of functional 2D hosts provides a pathway for uniting contraindicated properties.

Vanadium alkylidenes can be highly active initiators for ring-opening metathesis polymerization of cyclic olefins; however, attempts to expand their use to cross metathesis have been unsuccessful due to catalyst decomposition. Detailed knowledge of the decomposition reaction is imperative to guide future catalyst design. Herein, we demonstrate that β-hydride elimination is the dominant decomposition pathway during cross metathesis. The isolated vanadium decomposition products [N-2,6-(CH3)2C6H3](OC6Cl5)[P(CH3)3]2VCl (10) and [N-2,6-(CH3)2C6H3]V(OC6F5)2[P(CH3)3]2(11), generated from two separate catalysts, agree with this pathway. Compounds 10and 11were shown computationally to form via bimolecular routes after β-hydride elimination from the metallocyclobutane and reductive elimination of propylene, which was itself demonstrated to be exergonic with low thermodynamic barriers to metallocyclobutane formation. Relative conversions in the self-metathesis of 1-hexene with the series of vanadium alkylidenes of various sterics and electronics (N-2,6-X2C6H3)(OC6Y5)[P(CH3)3]2V[CHSi(CH3)3] [X = CH3, Y = Cl (1); X = CH(CH3)2, Y = Cl (6), X = CH(CH3)2, Y = F (7)] were determined. It was found that bulkier, yet more electron-donating ligands decreased conversions, indicating that β-hydride elimination is favored over bimolecular decomposition. Analysis of organic reaction products demonstrated that reductive elimination of propylene occurs before insertion of ethylene into the newly formed vanadium–hydrogen bond.

The synthesis of acyclic CB[n]-type host (1) is reported. By optimizing the placement of the sulfate groups nearby the electrostatically negative ureidyl C═O portals, the binding affinity of this class of receptors toward hydrophobic (di)ammonium guest molecules (5–23) is maximized. The X-ray crystal structures of 1·6aand 1·6dare reported.

A novel macrocyclic 1,7-dioxa-[2.1.1]-(2,6)-pyridinophane ligand has been synthesized and crystallographically characterized. Two derived metal complexes, dichloropalladium(II) and chlorocopper(I), were prepared. In the palladium(II) complex LPdCl2, both in the solid state, according to its crystallographic characterization, and in CH2Cl2solutions at −40 °C, according to 1H NMR spectroscopy, the ligand adapts a C1-symmetric κ2-N,N-coordination mode in which the metal atom binds to two nonequivalent pyridine fragments of the macrocycle. The complex is fluxional at 20 °C. In the crystalline copper(I) complex LCuCl, the macrocyclic ligand is also κ2-N,N-coordinated to the metal, but it utilizes two equivalent pyridine fragments for the binding. The copper(I) complex is fluxional in CH2Cl2solutions in the temperature range between 20 and −70 °C and is proposed to be involved in a fast intermolecular macrocyclic ligand exchange which is slowed down below −40 °C. DFT calculations predict a lower thermodynamic stability of the dioxapyridinophane-derived complexes LPdCl2and LCuCl, as compared to their [2.1.1]-(2,6)-pyridinophane analogs containing bridging CH2groups instead of the oxygen atoms. The electron poor dioxapyridinophane chlorocopper(I) complex, in combination with NaBArF4(BArF4= tetrakis[3,5-bis(trifluoromethyl)phenyl]borate) in dichloromethane solutions, can serve as an efficient catalyst for aziridination of various olefins with PhINTs at 0–22 °C.

We performed a comprehensive study of the fast relaxation processes in three metal–organic Ir(III)-complexes in liquid solutions at room temperature in order to estimate their singlet–triplet conversion quantum yields, ΦST. Experimental pico- and femtosecond transient absorption double pump–probe spectroscopy techniques were employed to reveal the peculiarities of the triplet population processes, and the corresponding values of ΦSTwere obtained based on a six-level electronic model. Our results confirm the fast population of triplets that has been observed before in Ir(III) complexes with characteristic times of ≤1–2 ps. Such fast transfer to the triplet usually indicates a triplet yield of unity; however, we observe that ΦSTis significantly less than the unity value previously reported for this class of compounds and expected. A six-level model explains the apparent contradiction between ultrafast triplet formation and subunity triplet quantum yield. It also explains the observation of simultaneous photoemission from singlet and triplet states.

A new structurally diverse ligand for metal complexes, the (κ2-N,N)-iminocaprolactam group, that can be obtained in large bulk quantities from inexpensive and readily available starting materials, is introduced. In the present report, the ability of this family of ligands to provide a viable substitute for the acyclic amidinate moiety of a class of cationic monocyclopentadienyl, amidinate (CPAM) group 4 metal initiators for the living coordination polymerization (LCP) and living coordinative chain transfer polymerization (LCCTP) of α-olefins is documented through the synthesis of (η5-C5Me5)Hf[(R)NimcapN](Me)2[R = benzyl (1), CH2(1-naphthyl) (2), and tert-butyl [C(CH3)3] (3)] as preinitiators for the (stereoselective) LCP and LCCTP of propene.

While 2D metal–organic hybrids have emerged as promising solar absorbers due to their improved moisture stability, their inferior transport properties limit their potential translation into devices. We report a new hybrid containing 2-(2-ammonioethyl)pyridine [(2-AEP)+], forming a 2D hybrid with the composition (2-AEP)2PbI4. The organic bilayer comprises of (2-AEP)+, which is arranged in a face-to-face stacking that promotes π–π interactions between neighboring pyridyl rings. We also demonstrate the structural diversity of 2-(2-aminoethyl)pyridine-based lead iodide hybrids in solution-processed films. This report highlights the importance of solution-processing conditions in trying to obtain single-phase films of hybrids containing dibasic organic species.

Transition metal chalcogenophosphates have garnered extensive attention owing to their diverse array of optical and magnetic properties. However, one of the less explored members within this family is CoPS3, largely due to the time-intensive nature of its solid-state synthesis preparation. In this study, we present an ion exchange metathesis methodology to address these challenges. Through the exploitation of the versatile thiophosphate motif, we have successfully synthesized CoPS3by reacting isostructural MgPS3with CoCl2. Our findings from ex situ investigations highlight a correlation between the degree of structural disorder and the concentration of CoCl2, impacting not only the bulk magnetism but also the observed phonon modes, as evidenced by magnetic susceptibility and Raman spectroscopy, respectively. This structural disorder seemingly plays a pivotal role in shaping the mechanism underlying the formation of CoPS3through the metathesis approach, which we comprehensively elucidate using in situ synchrotron powder X-ray diffraction. Our detailed analysis uncovers a two-step progression in the metathesis reaction involving ion diffusion kinetics and grain boundary melt phenomena. These insights not only enhance our understanding of the reaction dynamics but also pave the way for refining and optimizing the synthesis of such compounds with the desired structures and properties.

The C1-symmetric cyclopentadienyl, α,α,α-trifluoroacetamidinate (CPAMCF3) group 4 metal dimethyl complexes, Cp*[N(Et)C(CF3)N(tBu)]M(Me)2(Cp* = η5-C5Me5) for M = Zr (3) and Hf (4), serve as initiators for the stereoselective (isotactic) living coordination polymerization (LCP) of α-olefins upon in situ “activation” using one equiv of the borate co-initiator, [PhNMe2H][B(C6F5)4]. For the LCP of 1-hexene using 4, a six-fold enhancement in the rate of polymerization, Rp, is observed relative to the LCP of this same α-olefin when the nonfluorinated CPAMCH3structural analogue, Cp*[N(Et)C(CH3)N(tBu)Hf(Me)2] (2), is employed as the preinitiator. For the LCP of propene, an eight-fold increase in Rpusing the CPAMCF3preinitiator 4now permits production of practical quantities of highly stereo- and regioregular isotactic polypropene (iPP) under reaction conditions that are not amenable for use with the corresponding CPAMCH3preinitiator 2. These results provide strong support for a unique synergistic coupling of steric and electronic effects of the CPAMCF3ligand environment.

Aerobic C–H functionalization of benzene and a series of electron-rich and electron-poor arenes has been demonstrated using a Pt(II) aqua complex supported by a sulfonated CNN-chelating pincer ligand in wet 2,2,2-trifluoroethanol (TFE) solutions at 20 °C and ambient pressure of air or O2. The reaction results in Pt(IV) aryl hydroxo complexes and a Pt(IV) trifluoroethoxo complex as two major products, in a 1:1 molar ratio, along with minor Pt(II) products of the arene and pincer ligand oxidative C–C coupling.

A new polymorph of iodic acid, δ-HIO3, synthesized via aerosol spray pyrolysis was characterized with powder X-ray diffraction and its crystal structure was solved. We find that a previously misidentified phase of I4O9hydrate is in fact a new polymorph of HIO3, which crystalizes in the orthorhombic space group P212121.

Comprehensive investigations of the linear and nonlinear optical properties of new Ir(III) complexes [Ir(pbt)2(dbm)] (1), [Ir(pbt)2(dmac)] (2), and [Ir(pbt)2(minc)] (3) (pbt = 2-phenylbenzothiazole; dbm = dibenzoyl methane; dmac = (1E,4Z,6E)-1,7-bis(4-(dimethylamino)phenyl)-5-hydroxyhepta-1,4,6-trien-3-one; minc = (1E,4Z,6E)-5-hydroxy-1,7-bis(1-methyl-1H-indol-3-yl)hepta-1,4,6-trien-3-one) are reported, including photostability, two-photon absorption, and femtosecond transient absorption spectroscopy. The steady-state and time-resolved spectral properties of 1–3revealed the electronic nature of the absorption bands, and photoluminescence emission of 2and 3shows both fluorescence and phosphorescence processes occurring simultaneously in liquid solution at room temperature. This unusual behavior of 2and 3can be explained by a dual-minimum potential surface of the excited electronic state resulting in two independent fluorescence and phosphorescence emission channels. The degenerate 2PA spectra of 1–3were obtained by open aperture Z-scans with a femtosecond laser, and maxima values of 2PA cross sections up to ∼350 GM were observed. Ultrafast relaxation processes of 1–3were investigated by femtosecond transient absorption, and the characteristic times for triplet formation were determined to be <500 fs for 1and ∼2 ps for 2and 3in a nonpolar medium.

Green oxidation: A new class of Group 6 metal complexes catalyzes the direct oxidation of isocyanides through nondegenerate oxygen atom transfer (OAT) utilizing N2O as a chemical oxidant. In addition they serve as photocatalysts for the reversible degenerate OAT between CO and CO2(see scheme).

„Grüne“ Oxidation: Eine neue Klasse von Metallkomplexen der Gruppe 6 wird beschrieben, die die direkte Oxidation von Isocyaniden durch nichtentarteten Sauerstoffatomtransfer (OAT) mit N2O als Oxidationsmittel katalysieren. Die Komplexe dienen außerdem als Photokatalysator für den reversiblen entarteten OAT zwischen CO und CO2(siehe Schema).

Divergent catalysis: The use of copper and rhodium catalysts separately or in combination directs reactions between vinyldiazoacetates 1and cinnamaldehydes 2from formal [4+3] cycloaddition (epoxidation followed by Cope rearrangement), to intramolecular cyclopropanation, to Mukaiyama‐aldol reactions. The reactions proceed selectively and in high yield.

Divergente Katalyse: Je nach separater oder kombinierter Verwendung von Kupfer‐ und Rhodiumkatalysatoren wird die Reaktion zwischen Vinyldiazoacetaten 1und Cinnamaldehyden 2umgelenkt: von einer formalen [4+3]‐Cycloaddition (Epoxidierung mit anschließender Cope‐Umlagerung), zur intramolekularen Cyclopropanierung bis hin zur Mukaiyama‐Aldolreaktion. Die jeweiligen Reaktionen sind selektiv und liefern hohe Ausbeuten.

A hydroxlic solvent promoted reaction: Boron‐to‐platinum methyl‐group transfer occurs in the title complexes in the presence of an oxidant (O2or MeI) and a protic solvent (water, alcohols; see scheme). With MeI as oxidant the reaction intermediate is shown to be a five‐coordinate PtIVspecies containing a Pt⋅⋅⋅CH agostic interaction.

B3LYP* functionals were used to model the sixteen iron(ii) (1A, LS and 5T, HS) and iron(iii) (2T, LS and 6A, HS) complexes of the 1 : 3 Schiff base condensate of tris(2-aminoethyl)amine and imidazole-4-carboxaldehyde, H3L1, and its deprotonated forms, [H2L1]1−, [HL1]2−, and [L1]3−. This ligand system is unusual in that [FeH3L1]3+, [FeH3L1]2+ and [FeL1]− all exhibit a spin crossover between 100–300 K. This makes these complexes ideal for a hybrid DFT computational approach and provides an opportunity to refine the value of the exact exchange admixture parameter, c3, and to predict properties of partially protonated complexes that are not experimentally available. The accepted value of 0.20 is larger than the value of ∼0.13 that was found to best reproduce experimental data in terms of spin state predictions. With iron(iii) B3LYP calculations showed that all of the complexes were low spin at 298 K with the exception of [FeH3L1]3+ which is spin crossover in agreement with experimental results. It was also shown for iron(iii) that the ligand field increased as the number of protons decreased. In contrast all of the iron(ii) complexes were close to the spin crossover region regardless of protonation state. Experimental structures are fairly well modeled by this system in regard to the key structural indicators of spin state, which are the bite and trans angles. The calculated iron to nitrogen atom distances are always larger in the high spin form than the low spin form but all iron to nitrogen bond distances are larger than the experimental values. In general non-bonded interactions are not well modeled by this methodology.

The 1 : 3 Schiff base condensates of tris(2-aminoethyl)amine (tren) or tris(3-aminopropyl)amine (trpn) with 4-methyl-5-imidazolecarboxaldehyde, H3L1and H3L2, respectively, were generated in situ and used to prepare complexes with manganese(ii) and iron(iii). The resultant complexes, [MnH3L1](ClO4)2, [MnH3L1](ClO4)2·EtOH·H2O, [MnH3L2](ClO4)2, [FeH3L1](ClO4)3·1.5(EtOH) and [FeHL1](I3) 0.525(I)0.475·2.625H2O, have been characterized by EA, IR, ES MS, variable temperature magnetic susceptibility, X-ray crystallography, and Mössbauer spectroscopy for the iron complexes. The three manganese(ii) complexes are high spin with [MnH3L2](ClO4)2exhibiting coordination number seven while the others are six coordinate. [FeH3L1](ClO4)3·1.5(EtOH) has two iron sites, a seven coordinate and a pseudo seven coordinate site. The complex is high spin at room temperature but exhibits a magnetic moment that decreases with temperature corresponding to conversion of one of the sites to low spin. [FeHL1](I3) 0.525(I)0.475·2.625H2O is low spin even at room temperature. In the present complexes the apical nitrogen atom, Nap, of the tripodal ligand is pyramidal and directed toward the metal atom. The data show that the M–Napdistance decreases as the oxidation state of the metal increases, as the number of bound imidazole protons on the ligand increases, and as the number of carbon atoms in the backbone of the ligand (tren vs. trpn) increases. In a limiting sense, short M–Napdistances result in high spin seven coordinate mono capped octahedral complexes and long M–Napdistances result in low spin six coordinate octahedral complexes.

Iron and vanadium oxides have a rich structural chemistry when combined with phosphate groups; the transition metal most commonly in an octahedral coordination. The inductive effect increases the potential difference between Fe3+/Fe2+and Li/Li+couples in phosphate lattices relative to the pure iron oxides; a similar behavior is found for the corresponding vanadium compounds. Of the iron phosphates, the olivine phase LiFePO4has high thermal and chemical stability, even when lithium-free; the challenges of low electronic conductivity are being overcome, but data is lacking on the true lithium diffusion behavior. The all-ferric lipscombite-type phase, Fe1.33PO4OH, shows the highest capacity of the iron phosphates for lithium intercalation. The -VOPO4material, formed by the oxidative de-intercalation of protons from H2VOPO4, can reversibly react with two lithium atoms in two steps. The face- and edge-sharing transition metal octahedra lead to a range of interesting and structurally revealing magnetic interactions. A number of vanadium oxide phases are known, with those containing VO6octahedra showing the greatest stability when undergoing redox reactions. Such structures have been synthesized using xerogel, hydrothermal and electrochemical methods. The double-sheet delta structures show reversible lithium intercalation of up to one lithium ion per vanadium, leading to the highest storage capacities. However, the large potential width of discharge and the apparent low reaction rates will minimize their use unless improved.

The mixed transition metal layered compound, LiNi0.4Mn0.4Co0.2O2, with the α-NaFeO2layer structure has been synthesized and characterized. The optimum temperature of synthesis was found to be 800–900 °C. Rietveld refinement showed that cobalt suppresses transition metal ion migration into the Li sites whereas nickel promotes the migration. XPS analysis shows that the Co and about 20 of the Ni and Mn are in the 3 oxidation state, while 80 of the Ni and Mn are in the 2 and 4 oxidation states, respectively. LiNi0.4Mn0.4Co0.2O2shows Curie–Weiss paramagnetic behavior above 150 K, and the value of the Curie constant is consistent with the above oxidation states. In lithium electrochemical cells the composition LiNi0.4Mn0.4Co0.2O2gave the highest reversible capacity among the studied compositions. It shows excellent rate capability, giving reversible capacities ranging from 180 to 155 mA h g−1at current densities from 0.1 to 2.0 mA cm−2.

Four new layered mixed-valance vanadium oxides, which contain the interlamellar organic cations pyrolidinium, dimethylammonium, piperidinium, and ethylammonium, have been prepared under hydrothermal conditions and their structures determined. All four structures contain vanadium oxide layers constructed from V5+O₄ tetrahedra and pairs of V4+O₅ square pyramids with the protonated organic amines occupying the interlayer space. The materials are further characterized by thermal analysis, FTIR and scanning electron microscopy. Magnetic susceptibility studies of the first three compounds reveal a spin-gap behavior explained by an isolated antiferromagnetic dimers model. Large values of the exchange constants J = 325 − 480 K were found and the dependence of J upon the structural parameters was analyzed assuming a kinetic exchange mechanism.

The mixed transition metal layered compound, LiNi_0.4Mn_0.4Co_0.2O₂, with the α-NaFeO₂ layer structure has been synthesized and characterized. The optimum temperature of synthesis was found to be 800–900 °C. Rietveld refinement showed that cobalt suppresses transition metal ion migration into the Li sites whereas nickel promotes the migration. XPS analysis shows that the Co and about 20% of the Ni and Mn are in the 3+ oxidation state, while 80% of the Ni and Mn are in the 2+ and 4+ oxidation states, respectively. LiNi_0.4Mn_0.4Co_0.2O₂ shows Curie–Weiss paramagnetic behavior above 150 K, and the value of the Curie constant is consistent with the above oxidation states. In lithium electrochemical cells the composition LiNi_0.4Mn_0.4Co_0.2O₂ gave the highest reversible capacity among the studied compositions. It shows excellent rate capability, giving reversible capacities ranging from 180 to 155 mA h g−1 at current densities from 0.1 to 2.0 mA cm−2.

Four new layered mixed-valance vanadium oxides, which contain the interlamellar organic cations pyrolidinium, dimethylammonium, piperidinium, and ethylammonium, have been prepared under hydrothermal conditions and their structures determined. All four structures contain vanadium oxide layers constructed from V5O4tetrahedra and pairs of V4O5square pyramids with the protonated organic amines occupying the interlayer space. The materials are further characterized by thermal analysis, FTIR and scanning electron microscopy. Magnetic susceptibility studies of the first three compounds reveal a spin-gap behavior explained by an isolated antiferromagnetic dimers model. Large values of the exchange constants J  325 − 480 K were found and the dependence of Jupon the structural parameters was analyzed assuming a kinetic exchange mechanism.

Two methylammonium containing zinc phosphates, (CH₃NH₃)Zn₄(PO₄)₃ and (CH₃NH₃)₂Zn₅(PO₄)₄, have been synthesized hydrothermally from a mixture of zinc chloride, phosphoric acid and methylammonium hydroxide. (CH₃NH₃)Zn₄(PO₄)₃ crystallizes in space group Pbca, with a = 14.6797(6) Å, b = 10.1204(4) Å, c = 16.6015(7) Å and (CH₃NH₃)₂Zn₅(PO₄)₄ crystallizes in space group P2₁2₁2₁, with a = 7.265(2) Å, b = 13.432(4) Å, c = 18.078(5) Å. They have open framework structures formed by corner sharing of PO₄ and ZnO₄ tetrahedra with some of the oxygen atoms three-fold coordinated. One-dimensional tunnels are formed in both compounds, with the methylammonium template residing in the tunnels. There are extensive Zn–O–Zn chains in (CH₃NH₃)Zn₄(PO₄)₃; however, in (CH₃NH₃)₂Zn₅(PO₄)₄ the Zn–O–Zn bonding is restricted to isolated Zn₄O₁₂ units.

A new layered vanadium oxide, C5H5NHV3O7, has been synthesized by a solvothermal process at 200 °C; this is the first vanadium oxide to have an aromatic intercalate between the V3O7sheets, and it has a monoclinic structure with space group P21and lattice parameters a 7.52966 Å, b 6.65928 Å, c 10.151312 Å and β 94.4602°.

Two methylammonium containing zinc phosphates, CH3NH3Zn4PO43and CH3NH32Zn5PO44, have been synthesized hydrothermally from a mixture of zinc chloride, phosphoric acid and methylammonium hydroxide. CH3NH3Zn4PO43crystallizes in space group Pbca, with a 14.67976 Å, b 10.12044 Å, c 16.60157 Å and CH3NH32Zn5PO44crystallizes in space group P212121, with a 7.2652 Å, b 13.4324 Å, c 18.0785 Å. They have open framework structures formed by corner sharing of PO4and ZnO4tetrahedra with some of the oxygen atoms three-fold coordinated. One-dimensional tunnels are formed in both compounds, with the methylammonium template residing in the tunnels. There are extensive Zn–O–Zn chains in CH3NH3Zn4PO43; however, in CH3NH32Zn5PO44the Zn–O–Zn bonding is restricted to isolated Zn4O12units.

The solvothermal reaction, at 200 °C, of vanadium pentoxide and lithium hydroxide in acetic acid or ethylene glycol leads to the formation of vanadyl acetate and vanadyl glycolate respectively. The structure of the acetate contains vanadium in octahedral coordination whereas the glycolate contains VO5square pyramids. The VO6octahedra in the acetate, VOCH3COO2, are joined through the vanadyl groups, giving a rather long VO bond of 1.6847 Å and a short transV-O bond of 2.1317 Å, and by bridging acetate groups. The vanadium atoms interact along the VOVO chain giving one-dimensional antiferromagnetic behavior. In contrast in the glycolate, the apical VO bond is shorter, 1.581 Å, and the square pyramids share edges in a two up–two down fashion to give chains of formula VOOCH2CH2O. Magnetic susceptibility of vanadyl glycolate is consistent with an isolated spin dimers model.

A new layered vanadium oxide, (C₅H₅NH)V₃O₇, has been synthesized by a solvothermal process at 200 °C; this is the first vanadium oxide to have an aromatic intercalate between the V₃O₇ sheets, and it has a monoclinic structure with space group P2₁ and lattice parameters a = 7.5296(6) Å, b = 6.6592(8) Å, c = 10.1513(12) Å and β = 94.460(2)°.

The solvothermal reaction, at 200 °C, of vanadium pentoxide and lithium hydroxide in acetic acid or ethylene glycol leads to the formation of vanadyl acetate and vanadyl glycolate respectively. The structure of the acetate contains vanadium in octahedral coordination whereas the glycolate contains VO₅ square pyramids. The VO₆ octahedra in the acetate, VO(CH₃COO)₂, are joined through the vanadyl groups, giving a rather long V&z.dbd;O bond of 1.684(7) Å and a short trans V-O bond of 2.131(7) Å, and by bridging acetate groups. The vanadium atoms interact along the ⋯V&z.dbd;O⋯V&z.dbd;O⋯ chain giving one-dimensional antiferromagnetic behavior. In contrast in the glycolate, the apical V&z.dbd;O bond is shorter, 1.58(1) Å, and the square pyramids share edges in a two up–two down fashion to give chains of formula VO(OCH₂CH₂O). Magnetic susceptibility of vanadyl glycolate is consistent with an isolated spin dimers model.

Reaction of 2,2′‐bi­pyridine (bpy) and copper(II) nitrate in methanol results in two complexes, namely light‐blue bis(2,2′‐bi­pyridine)­nitrato­copper(II) nitrate methanol solvate, [Cu(NO3)(C10H8N2)2]NO3·CH3OH, (I), which is unstable in air, and the product of its decomposition, catena‐poly­[[[bis(2,2′‐bi­pyridine)copper(II)]‐μ‐nitrato‐O:O′] nitrate], {[Cu(NO3)(C10H8N2)2]NO3}n, (II). The crystal structures of both compounds were determined from one crystal at room temperature. Later, the structure of (I) was redetermined at low temperature. In (I) and (II), the Cu atom is coordinated by two bpy and one or two nitrate ions, respectively. The second nitrate ion in (I), along with the methanol solvent mol­ecule, is found in the outer coordination sphere, not bonded to Cu. The nitrate in (I) is chelating, while in (II), it bridges (bpy)2Cu complexes, forming a one‐dimensional chain structure. The Cu cation in (II) lies on a twofold axis and the uncoordinated NO3−ion is located close to a twofold axis and is therefore disordered. Compound (I) converts into (II) upon loss of solvent.

Vanadium and manganese oxides can be readily synthesized using soft chemical approaches, such as hydrothermal, sol–gel, intercalation and ion-exchange. By controlling the pH and organic reactants/templates it is possible to control the structure formed by controlling the species in solution. In the case of vanadium, its coordination number increases as the pH decreases. It is found that the higher the vanadium coordination number the better the behavior of the oxide as a cathode material in lithium cells; tetrahedral vanadium is not reduced without destruction of the structure, whereas octahedral vanadium as in the delta double sheet structure holds its structure during reduction. Manganese oxides can also be synthesized using hydrothermal methods, with layered structures formed when small cations are present and tunnel structures when larger cations or anions are present. A range of mixed vanadium manganese oxides has been prepared, the structure depending on the organic cation and vanadium-to-manganese ratio. In several cases these are pillared oxides, that readily react with intercalating cations.

Two sulfonated CNN-pincer ligands L1 and L2 were used to explore the oxidative functionalization of the PtII-Me bond in derived K[(L)PtIIMe] complexes (L = L1 and L2) using O2and H2O2as oxidants (HL1–= (6-phenylpyrid-2-yl)(pyrid-2-yl)methanesulfonate; HL2–= (6-phenylpyrid-2-yl)-6,7-dihydro-5H-cyclopenta [b]pyridine-7-sulfonate). Oxidation with O2of K[(L1)PtIIMe] in MeOH produced a single high-valent platinum complex, (L1)PtIVMe2, whereas the use of H2O2led to (L1)PtIVMe(OH), 10c, and (L1)2PtIV2Me2(μ-OH)2, 14, having different configurations of a PtIVcenter. Oxidation of a more rigid analog, K[(L2)PtIIMe], with O2led to diastereomeric complexes (L2)PtIVMe(OH), 11d, in MeOH and 11a(detected as an adduct with the CF3CH2O–anion) in acetone/2,2,2-trifluoroethanol mixtures. The use of H2O2led to (L2)PtIVMe(OH), 11c, and (L2)2PtIV2Me2(μ-OH)2, 15, the analogs of 10cand 14, respectively. When heated with CF3CO2H in aqueous DMSO, MeOH, or acetone at 80 °C, (L)PtIVMe(OH) complexes produced in high yield either MeOH and MeO2CCF3or C(sp2)-C(sp3) coupled products involving a carbon atom of pincer ligands. DFT calculations were used to analyze the observed reactivity. It was concluded that the key factors favoring the C(sp3)-O coupling are the trans-arrangement of the methyl ligand and the sulfonate group, the use of CF3CO2–as an O-nucleophile and DMSO as a solvent favoring the generation of highly electrophilic PtIVMe intermediates.

[Nb(η6-C6H3Me3)2] reacts with ethylenediamine (en) solutions of K4Ge9in the presence of 18-crown-6 to give [(η6-C6H3Me3)NbHGe6]2–(1) and [(η6-C6H3Me3)NbGe6Nb(η6-C6H3Me3)]2–(2) as their corresponding [K(18-crown-6)]+salts. The crystalline solids are dark brown, air-sensitive, and sparingly soluble or insoluble in most solvents. The [K(18-crown-6)]+salts of cluster ions 1and 2have been characterized by energy-dispersive X-ray (EDX) analysis, NMR studies, single-crystal X-ray diffraction, and electrospray ionization time-of-flight (ESI-TOF) mass spectrometry studies. Cluster ions 1and 2have markedly different [Ge6] moieties: an electron-deficient carborane-like subunit in 1and a two-center, two-electron cyclohexane-like subunit in 2.

Transition-metal thiophosphates and selenophosphates are layered systems with the potential for displaying two-dimensional (2D) magnetic phenomena. We present the crystal structures and magnetic properties of two lithium transition-metal thiophosphates, Li1.56Co0.71P2S6and Li2.26Fe0.94P2S6. The previously unreported Li1.56Co0.71P2S6crystallizes in the trigonal space group P31mwith lattice parameters a= 6.0193(6) Å and c= 6.5675(9) Å. The CoS6octahedra are arranged in a honeycomb lattice and form 2D layers separated by lithium cations. The previously solved Li2.26Fe0.94P2S6is isostructural to Li1.56Co0.71P2S6but displays site mixing between the Li+and Fe2+cations within the thiophosphate layer. Unusually, Li1.56Co0.71P2S6appears to have P2S63–and not P2S64–anions. We therefore term it a “noninnocent” anion because of the ambiguous nature of its oxidation state. Combined neutron diffraction and magnetization measurements reveal that both Li1.56Co0.71P2S6and Li2.26Fe0.94P2S6display magnetic anisotropy as well as no long-range magnetic order down to 5 K. In the iron thiophosphate, susceptibility indicates an effective moment of 5.44(3) μB, which may be best described by an S+ Lmodel, where S= 2 and L= 2, or close to the free ion limit. In the cobalt thiophosphate, we found the effective moment to be 4.35(2) μB, which would point to an S= 3/2and L= 1 model due to octahedral crystal-field splitting.

The C3-symmetric triamide 1selectively transports NO3−anions across lipid vesicles: this H+–NO3−co-transporter alters the pH inside of liposomes experiencing a NO3−/Cl−gradient.

Material properties of parts made via selective laser melting are not the same as the well-established properties for bulk base materials, due to the unique processes used to produce the parts. Meanwhile, additive manufacturing is increasingly being used for heat exchangers and heat removal devices, which demand high thermal conductivities. The thermal properties are also important for many non-destructive testing technologies. The thermal conductivity of selective laser melted 316 L stainless steel was studied as a function of processing conditions and build orientation. The porosity and thermal conductivity were measured versus processing conditions. A critical energy density of 44.4 J/mm3was observed below which the porosity increased and the thermal conductivity decreased. For the lowest-porosity sample, the local thermal conductivity map taken with frequency domain thermoreflectance showed a variation in the stainless steel thermal conductivity between 10.4 and 19.8 W/m-K, while the average thermal conductivity of 14.3 W/m-K from the thermal conductivity map agreed, within measurement uncertainty, with the bulk thermal conductivity measurements. The thermal conductivity trend was not fully explained by the porosity, as effective medium models fail to predict the trend. Amorphous stripes in the selective laser melted stainless steel grains were identified by transmission electron microscopy. These amorphous regions also resulted in decreased x-ray diffraction intensities with increasing porosity. The amorphous regions are hypothesized to lower the thermal conductivity at faster laser scanning speeds due to less time at elevated temperatures. We also found that in-print plane and through-print plane thermal conductivities have the same value when the energy density is greater than this critical amount. When the energy density reduces below this critical amount, the in-plane conductivity exceeds the through-plane.

Poly­[tin(II)‐μ‐phenyl­phospho­nato], [Sn(C6H5O3P)]n, was synthesized solvothermally at 423 K and crystallized in the monoclinic system, space group Cc. The inorganic layers consist of alternating pyramidal Sn and tetrahedral P centers, joined by doubly bridging O atoms. The corner‐sharing SnO3and PO3C6H5polyhedra define a corrugated layer of six‐membered rings. The layers are connected along the unique baxis by interdigitated phenyl rings of the phenyl­phospho­nate groups.

Hydro­thermally prepared dilithium tin hexa­hydro­xide crystallizes in the monoclinic system (space group P21/n), with the Sn atom at a site with symmetry and all other atoms in general positions. The Sn coordination polyhedron is made up of six hydro­xide groups. The Li atom is tetrahedrally coordinated by oxy­gen, with the tetrahedra sharing two corners and one edge with the adjacent Sn octahedra. Hydro­gen bonds between the OH groups provide additional bonds in the framework.

The title compound, NaV3(SO4)2(OH)6, was synthesized and found to crystallize in the trigonal space group Rmwith the Na atom at a site with 3¯msymmetry, the V atom at a site with 2/msymmetry, and the S and a terminal O atom at sites with 3msymmetry; the remaining two O atoms and the H atom are at sites with msymmetry. Octahedrally coordinated vanadium and tetrahedral sulfate ions share corners to form layers that are held together by hydrogen bonds and by sodium ions, which are located between the layers.

The reaction between vinyl diazoacetates and cinnamaldehydes can be highly selectively directed to the formation of 4,5‐dihydrooxepins or bicyclic hexanones by appropriate use of Cu‐ and Rh‐catalyst, either separately or in combination.

The copper‐catalyzed Mannich addition is followed by rhodium‐catalyzed dinitrogen extrusion.

Various 1,2‐oxazine derivatives can be prepared with good to high enantioselectivity.

Nanoparticles of the title compound are prepared by slow mixing of an aqueous K4[Fe(CN)6] solution containing polyvinylpyrrolidone with an aqueous Bi(NO3)3solution containing sodium citrate (room temperature, 30 min).

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

For Abstract see ChemInform Abstract in Full Text.

For Abstract see ChemInform Abstract in Full Text.