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Layered copper–nickel cyanide, CuNi(CN)4, a 2-D negative thermal expansion material, is one of a series of copper(ii)-containing cyanides derived from Ni(CN)2. In CuNi(CN)4, unlike in Ni(CN)2, the cyanide groups are ordered generating square-planar Ni(CN)4 and Cu(NC)4 units. The adoption of square-planar geometry by Cu(ii) in an extended solid is very unusual. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to analyse the economic growth of China and India in terms of their integration in the global economy. We begin with a discussion of some stylized facts concerning their recent economic growth, the most significant institutional reforms, with particular reference to trade relations, and their impact on their economic development. We then propose a descriptive analysis of economic growth, opening up of the economies and trade specialisation, by comparing the features and trends of the two countries (by considering trade and foreign direct investment data). We have also estimated some econometric relations between economic growth and trade/openness, with the addition of control variables (such as the gross fixed capital formation). We initially used a panel data model for the two countries, to be estimated with fixed effects; to test for reverse causality, we re-estimated the fixed effects model by 2SLS (with the inclusion of specific instrumental variables). The effect on economic growth (in terms of GDP per capita) of our variables of interest - Openness and FDI - remains positive and statistically significant in all specifications, which confirms our findings even if we treat these variables as endogenous variables. The results prove the positive growth effects, for the two countries, of opening up and integrating in the world economy. Note that the robust growth of these two "giants" has contained the initial impact of the recent global crisis and is now sustaining the recovery of the entire world economy. Other policy relevant implications are discussed in the concluding section.

Zn (CN)2 and Ni(CN)2 are known for exhibiting anomalous thermal expansion over a wide temperature range. The volume thermal expansion coefficient for the cubic, three-dimensionally connected material, Zn(CN)2, is negative (αV = -51 × 10-6 K-1) while for Ni(CN)2, a tetragonal material, the thermal expansion coefficient is negative in the two-dimensionally connected sheets (αa= -7 × 10-6 K-1), but the overall thermal expansion coefficient is positive (αV = 48 × 10-6 K-1). We have measured the temperature dependence of phonon spectra in these compounds and analyzed them using ab initio calculations. The spectra of the two compounds show large differences that cannot be explained by simple mass renormalization of the modes involving Zn (65.38 amu) and Ni (58.69 amu) atoms. This reflects the fact that the structure and bonding are quite different in the two compounds. The calculated pressure dependence of the phonon modes and of the thermal expansion coefficient, αV, are used to understand the anomalous behavior in these compounds. Our ab initio calculations indicate that phonon modes of energy ∼2 meV are major contributors to negative thermal expansion (NTE) in both compounds. The low-energy modes of ∼8 and 13 meV also contribute significantly to the NTE in Zn(CN)2 and Ni(CN)2, respectively. The measured temperature dependence of the phonon spectra has been used to estimate the total anharmonicity of both compounds. For Zn(CN)2, the temperature-dependent measurements (total anharmonicity), along with our previously reported pressure dependence of the phonon spectra (quasiharmonic), is used to separate the explicit temperature effect at constant volume (intrinsic anharmonicity). [ABSTRACT FROM AUTHOR]

Cellulose nanofibers (CNF) are the most abundant renewable nanoscale fibers on Earth, and their use in the design of hybrid materials is ever more acclaimed, although it has been mostly limited, to date, to CNF derivatives obtained via covalent functionalization. Herein, we propose a noncovalent approach employing a set of short peptides - DFNKF, DF(I)NKF, and DF(F 5 )NKF - as supramolecular additives to engineer hybrid hydrogels and films based on unfunctionalized CNF. Even at minimal concentrations (from 0.1% to 0.01% w/w), these peptides demonstrate a remarkable ability to enhance CNF rheological properties, increasing both dynamic moduli by more than an order of magnitude. Upon vacuum filtration of the hydrogels, we obtained CNF-peptide films with tailored hydrophobicity and surface wettability, modulated according to the peptide content and halogen type. Notably, the presence of fluorine in the CNF-DF(F 5 )NKF film, despite being minimal, strongly enhances CNF water vapor barrier properties and reduces the film water uptake. Overall, this approach offers a modular, straightforward method to create fully bio-based CNF-peptide materials, where the inclusion of DFNKF derivatives allows for facile functionalization and material property modulation, opening their potential use in the design of packaging solutions and biomedical devices.

Background: Imbalanced angiogenesis is characteristic of normal placental maturation but it also signals placental dysfunction, underlying hypertensive disorders during pregnancy. This study aimed to investigate the relationship between angiogenic placental aging, measured by markers placental growth factor (PlGF) and soluble fms-like tyrosine kinase-1 (sFlt-1) using the new index "Multiples of a normal term placenta" (Mtp) and the duration of pregnancy. Methods: A retrospective observational study was conducted, including singleton pregnancies diagnosed or suspected of hypertensive disorders after the 20th gestational week. Mtp measures how far a single dosage of angiogenic marker deviates from the expected value in an uncomplicated full-term pregnancy (Mpt = sFlt-1/sFlt-1 reference value or PIGF/PIGF reference value). We considered the 90th, 95th, and 97.5th centiles for sFlt-1 and the 2.5th, 5th, and 10th centiles for PlGF as references. Results: The categories with longer time to delivery, regardless of gestational age, were: Mtp PlGF 10th c ≥ 2, ≥3 and Mtp sFlt-1 90th c ≤ 0.5 (median days of 9, 11, 15 days, respectively). These two categories Mtp sFlt-1 90th c ≥ 3 and Mtp sFlt-1 97.5th c ≥ 2 allow the identification of women at risk for imminent delivery within 1 day. Women who were deemed at low/medium risk based on the sFlt-1/PIGF ratio appeared to be at high risk when considering the individual values of sFlt-1 and/or PIGF. Conclusions: This new Mtp index for sFlt-1 and PlGF could be employed to assess the degree of placental aging in women with hypertensive disorders. It represents a valid tool for evaluating the risk of imminent birth, irrespective of gestational age, surpassing the current stratification based on the sFlt-1/PIGF ratio.

Sox2 is known for its roles in maintaining the stem cell state of embryonic stem cells and neural stem cells. In particular, it has been shown to slow the proliferation of these cell types. It is also known for its effects as an activating transcription factor. Despite this, analysis of published studies shows that it represses as many genes as it activates. Here, we identify a new set of target genes that Sox2 represses in neural stem cells. These genes are associated with centrosomes, centromeres and other aspects of cell cycle control. In addition, we show that SUMOylation of Sox2 is necessary for the repression of these genes and for its repressive effects on cell proliferation. Together, these data suggest that SUMO-dependent repression of this group of target genes is responsible for the role of Sox2 in regulating the proliferation of neural stem cells., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Marelli et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Maternal nutritional status represents a pivotal predictor of pregnancy outcome. This prospective observational study investigates the associations between maternal characteristics and nutritional habits at term, hemodynamic parameters, and pregnancy outcomes. Healthy women with singleton uncomplicated pregnancies were enrolled at 36-41 gestational weeks. At enrollment, a nutritional score (0-10) was calculated in order to quantify maternal adherence to a healthy diet and lifestyle. Maternal hemodynamic parameters were assessed by using the Ultrasonic Cardiac Output Monitor (USCOM), including cardiac output (CO), systemic vascular resistance (SVR) and Smith-Madigan inotropy index (SMII). Pregnancy outcomes were recorded at delivery. Associations between maternal characteristics and nutritional score, hemodynamic parameters, and pregnancy outcomes were investigated by using multi-adjusted generalized linear models. In total, 143 pregnancies were enrolled. Pregestational body mass index (BMI) was positively associated with SVR, and negatively associated with CO and SMII. Additionally, a positive association was detected between the nutritional score and SMII. Finally, CO was positively associated with birth and placental weight, while RVS showed a negative association with birth and placental weight. This study shows that maternal derangements in nutritional status and habits are associated with a compromised hemodynamic profile at term, with additional impacts on intrauterine growth.

Background Aviation professionals are often exposed to conditions such as low cabin air pressure, reduced humidity, and prolonged artificial lighting, which may predispose them to dry eye disease (DED). We therefore designed a cross-sectional study with three primary objectives. Our first aim was to determine the prevalence of subjective dry eye symptoms among civil flight personnel. To achieve this, we administered the Standard Patient Evaluation of Eye Dryness (SPEED) questionnaire. Second, we performed ocular examinations to assess objective DED indicators, such as the Schirmer's-1 (SCH-1) test and tear film break-up time (TBUT). We then correlated the results of these objective tests with the subjective symptoms reported by the participants. Last, we aimed to identify the independent risk factors for positive SCH-1 and TBUT results among aircrew personnel who did not report subjective dry eye symptoms. Methods The study sample consisted of 189 aircrew personnel (94 men and 95 women; mean age: 35.8 ± 10.4 years). They completed the SPEED questionnaire, a tool for assessing ocular surface symptoms. Participants' symptoms were classified as normal (SPEED scores 0-6), moderate (SPEED scores 7-15), or severe (SPEED scores 16-28). The objective assessment included the SCH-1 test for tear production and the TBUT test for tear film quality. Results A significant majority of participants (n = 165; 87.3%) did not report any subjective symptoms of DED. However, 12.2% (n = 23) and 0.5% (n = 1) of the study subjects experienced moderate and severe symptoms, respectively. The SCH-1 test and TBUT test were positive in 25.4% (n = 48) and 24.9% (n = 47) of the participants, respectively. Interestingly, among the aircrew personnel who did not report any subjective dry eye symptoms (SPEED scores 0-6), 18.8% (n = 31) and 17.6% (n = 29) showed abnormal results on the SCH-1 test and TBUT, respectively. Age was identified as the only independent predictor of a positive TBUT (odds ratio = 1.05, 95% confidence interval (CI) = 1.01-1.08, p = 0.01), with a borderline significant association with a positive SCH-1 test (odds ratio = 1.03, 95% CI = 0.99-1.07, p = 0.06). Conclusions The disparity between subjective symptoms and objective tests emphasizes the significance of incorporating objective measures for screening and diagnosing DED in civil flight personnel. If independently confirmed by future research, our findings could potentially lead to the routine implementation of surveillance protocols that incorporate objective DED indicators. Moreover, as age emerged as an independent predictor of positive results on objective tests, it is crucial to consider age-specific screening strategies., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2024, Fachinetti et al.)

Unilateral non-hemorrhagic adrenal infarction (NHAI) is a very uncommon cause of acute abdomen in pregnancy. Diagnosis is highly challenging due to its rarity, heterogeneity of clinical presentation, and inconclusiveness of the initial workup. Timely recognition is pivotal to ensuring optimal outcomes. Here we describe a case of spontaneous unilateral NHAI diagnosed in a singleton pregnant woman at 32 weeks' gestation at our centre and provide the findings of an extensive literature review on the topic. We identified 22 articles describing 31 NHAI cases in 30 obstetric patients: NHAI occurs more frequently on the right side and in the third trimester, and diagnosis is formulated more than 24 h after clinical presentation in 50% of cases; second-level imaging is always necessary to reach a definitive diagnosis and start appropriate treatment. A high degree of clinical suspicion is needed to promptly recognize NHAI in pregnancy, thus allowing appropriate multidisciplinary management and timely treatment initiation. Promotion of knowledge and awareness of NHAI as a potential cause of acute abdomen in pregnancy is mandatory to improve clinical practice and, ultimately, perinatal outcomes.

Co-based perovskite oxides are intensively studied as promising catalysts for electrochemical water splitting in an alkaline environment. However, the increasing Co demand by the battery industry is pushing the search for Co-free alternatives. Here we report a systematic study of the Co-free layered perovskite famil y RBaCuFeO 5+ δ (R = 4f lanthanide), where we uncover the existence of clear correlations between electrochemical properties and several physicochemical descriptors. Using a combination of advanced neutron and X-ray synchrotron techniques with ab initio DFT calculations we demonstrate and rationalize the positive impact of a large R ionic radius in their oxygen evolution reaction (OER) activity. We also reveal that, in these materials, Fe 3+ is the transition metal cation the most prone to donate electrons. We also show that similar R 3+ /Ba 2+ ionic radii favor the incorporation and mobility of oxygen in the layered perovskite structure and increase the number of available O diffusion paths, which have an additional, positive impact on both, the electric conductivity and the OER process. An unexpected result is the observation of a clear surface reconstruction exclusively in oxygen-rich samples ( δ > 0), a fact that could be related to their superior OER activity. The encouraging intrinsic OER values obtained for the most active electrocatalyst (LaBaCuFeO 5.49 ), together with the possibility of industrially producing this material in nanocrystalline form should inspire the design of other Co-free oxide catalysts with optimal properties for electrochemical water splitting., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The coordination of secondary phosphine oxides (SPO) was shown to efficiently promote the activation of C(sp 2 )-I bonds by gold, as long as a base is added (NEt 3 , K 2 CO 3 ). These transformations stand as a new type of chelation-assisted oxidative addition to gold. The role of the base and the influence of the electronic properties of the P-ligand were analyzed computationally. Accordingly, the oxidative addition was found to be dominated by Au→(Ar-I) backdonation. In this case, gold behaves similarly to palladium, suggesting that the inverse electron flow reported previously (with prevailing (Ar-I)→Au donation, resulting in faster reactions of electron-enriched substrates) is a specific feature of electron-deficient cationic gold(I) complexes. The reaction gives straightforward access to (P=O,C)-cyclometallated Au(III) complexes. The possibility to chemically derivatize the SPO moiety at Au(III) was substantiated by protonation and silylation reactions., (© 2023 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

The chemistry of (P,C)-cyclometalated complexes derived from naphthyl phosphines [ Np (P,C)M] is presented and analysed in this review. The three main synthetic approaches, namely P-chelation assisted C-H activation, oxidative addition and transmetalation, are described and compared. If a naphthyl framework inherently predisposes a phosphorus atom and transition metal to interact, a rigid metallacycle may induce some strain and distortion, as apparent from the survey of the single-crystal X-ray diffraction structures deposited in the Cambridge Structural Database (77 entries with metals from groups 7 to 11). Generally, the Np (P,C)-cyclometalation imparts high thermal and chemical robustness to the complexes, and a variety of stoichiometric reactions have been reported. In most cases, the metalacyclic structure is retained, but protodecyclometalation and ring-expansion have been sparingly observed. [ Np (P,C)M] complexes have also proved to be competent and actually competitive catalysts in several transformations, and they act as key intermediates in some others. In addition, interesting phosphorescence properties have been occasionally pointed out.

The development of mild, aqueous conditions for the cross-coupling of highly functionalized (hetero)aryl chlorides or bromides is attractive, enabling their functionalization and diversification. Herein, we report a general method for Suzuki-Miyaura cross-coupling at 37 °C in aqueous media in the presence of air. We demonstrate application of this general methodology for derivatisation of (poly)chlorinated, medicinally active compounds and halogenated amino acids. The approach holds the potential to be a useful tool for late-stage functionalization or analogue generation., Competing Interests: There are no conflicts to declare., (This journal is © the Partner Organisations.)

The role of the perovskite lattice oxygen in the oxygen evolution reaction (OER) is systematically studied in the PrBaCo 2 O 5+δ family. The reduced number of physical/chemical variables combined with in-depth characterizations such as neutron dif-fraction, O K-edge X-ray absorption spectroscopy (XAS), electron energy loss spectroscopy (EELS), magnetization and scanning transmission electron microscopy (STEM) studies, helps investigating the complex correlation between OER activity and a single perovskite property, such as the oxygen content. Larger amount of oxygen vacancies appears to facilitate the OER, possibly contributing to the mechanism involving the oxidation of lattice oxygen, i.e., the lattice oxygen evolution reaction (LOER). Furthermore, not only the number of vacancies but also their local arrangement in the perovskite lattice influences the OER activity, with a clear drop for the more stable, ordered stoichiometry., (© 2021 Wiley-VCH GmbH.)

The commercial success of the electrochemical energy conversion technologies required for the decarbonization of the energy sector requires the replacement of the noble metal-based electrocatalysts currently used in (co-)electrolyzers and fuel cells with inexpensive, platinum-group metal-free analogs. Among these, Fe/N/C-type catalysts display promising performances for the reduction of O 2 or CO 2 , but their insufficient activity and stability jeopardize their implementation in such devices. To circumvent these issues, a better understanding of the local geometric and electronic structure of their catalytic active sites under reaction conditions is needed. Herein we shed light on the electronic structure of the molecular sites in two Fe/N/C catalysts by probing their average spin state with X-ray emission spectroscopy (XES). Chiefly, our in situ XES measurements reveal for the first time the existence of reversible, potential-induced spin state changes in these materials., (© 2021 Wiley-VCH GmbH.)

An original multi-cooperative catalytic approach was developed by combining metal-ligand cooperation and Lewis acid activation. The [(SCS)Pd] 2 complex featuring a non-innocent indenediide-based ligand was found to be a very efficient and versatile catalyst for the Conia-ene reaction, when associated with Mg(OTf) 2 . The reaction operates at low catalytic loadings under mild conditions with HFIP as a co-solvent. It works with a variety of substrates, including those bearing internal alkynes. It displays complete 5- exo vs. 6- endo regio-selectivity. In addition, except for the highly congested t Bu-substituent, the reaction occurs with high Z vs. E stereo-selectivity, making it synthetically useful and complementary to known catalysts., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Background: Delirium may be one of the presenting symptoms of COVID-19, complicating diagnosis and care of elderly patients with dementia. We aim to identify the prevalence and prognostic significance of delirium as the sole onset manifestation of COVID-19., Methods: This is a retrospective single-centre study based on review of medical charts, conducted during the outbreak peak (March 27-April 18, 2020) in a Lombard dementia facility, including 59 elderly subjects with dementia and laboratory-confirmed COVID-19., Findings: Of the 59 residents, 57 (96⋅6%) tested positive (mean age: 82⋅8; women: 66⋅7%). Comorbidities were present in all participants, with 18/57 (31⋅6%) having three or more concomitant diseases. Delirium -Onset COVID-19 (DOC) was observed in 21/57 (36⋅8%) subjects who were chiefly older (mean age: 85⋅4 y/o) and with multiple comorbidities. Eleven/21 DOC patients (52⋅4%) had hypoactive delirium , while hyperactive delirium occurred in ten/21 (47⋅6%). Lymphopenia was present in almost all subjects (median: 1⋅3 × 10 9 /L). Overall mortality rate was 24⋅6% (14/57) and dementia severity per se had no impact on short-term mortality due to COVID-19. DOC was strongly associated with higher mortality ( p <0⋅001). Also, DOC and male gender were independently associated with increased risk of mortality (OR: 17⋅0, 95% CI: 2⋅8-102⋅7, p  = 0⋅002 and 13⋅6, 95% CI: 2⋅3-79⋅2, p  = 0⋅001 respectively)., Interpretation: Delirium occurrence in the elderly with dementia may represent a prodromal phase of COVID-19, and thus deserves special attention, especially in the presence of lymphopenia. Hypoxia and a severe inflammatory state may develop subsequently. DOC cases have higher short-term mortality rate., Funding: None., Competing Interests: None, (© 2020 The Author(s).)

Blending synthetic biology and synthetic chemistry represents a powerful approach to diversity complex molecules. To further enable this, compatible synthetic tools are needed. We report the first Buchwald Hartwig amination reactions with unprotected halotryptophans under aqueous conditions and demonstrate this methodology is applicable also to the modification of unprotected tripeptides and the natural product barettin.

Density functional theory (DFT) has proven to be an invaluable and effective tool for identifying highly active electrocatalysts for the oxygen evolution reaction (OER). Herein, we take a computational approach to first identify a series of rare-earth pyrochlore oxides based on Ir and Ru as potential OER catalysts. The DFT-based phase diagrams, Pourbaix diagrams (E vs pH), projected density of states, and band energy diagrams were used to identify prospective OER catalysts based on rare-earth Ir and Ru pyrochlores. The predicted materials were synthesized using the spray-freeze freeze-drying approach to afford nanoparticulate oxides conforming to the pyrochlore structural type A 2 B 2 O 7 where A = Nd, Gd, or Yb and B = Ir or Ru. In agreement with the computed Pourbaix diagrams, the materials were found to be moderately stable under OER conditions. All prepared materials show higher stability as compared to the benchmark IrO 2 catalyst, and the OER mass activity of Yb 2 Ir 2 O 7 and the ruthenate pyrochlores (Nd 2 Ru 2 O 7 , Gd 2 Ru 2 O 7 , and Yb 2 Ru 2 O 7 ) were also found to exceed those of the benchmark IrO 2 catalyst. We find that the OER activity of each pyrochlore series (i.e., iridate or ruthenate) generally improves as the size of the A-site cation decreases, indicating that maintaining control over the structure can be used to influence the electrocatalytic properties.

A new mechanism is proposed for the Ni-catalyzed carboxylation of organoboronates with CO 2 . DFT investigations at the PBE0-D3 level have shown that direct CO 2 addition to the catalysts [Ni(NHC)(Allyl)Cl] (1 NHC , NHC=IMe, IPr, SIPr and IPr*) is kinetically disfavored and formation of the Aresta-type intermediate is unlikely to occur. According to the mechanism proposed here, the carboxylation process starts with addition of the borate species to 1 NHC , followed by transmetalation, CO 2 cycloaddition and carboxylation. The rate-determining step was identified as being the transmetalation process, with computed relative free energy barriers of 34.8, 36.8, and 33.5 kcal mol -1 for 1 IPr , 1 SIPr and 1 IPr* , respectively., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Marrying synthetic biology with synthetic chemistry provides a powerful approach toward natural product diversification, combining the best of both worlds: expediency and synthetic capability of biogenic pathways and chemical diversity enabled by organic synthesis. Biosynthetic pathway engineering can be employed to insert a chemically orthogonal tag into a complex natural scaffold affording the possibility of site-selective modification without employing protecting group strategies. Here we show that, by installing a sufficiently reactive handle (e.g., a C-Br bond) and developing compatible mild aqueous chemistries, synchronous biosynthesis of the tagged metabolite and its subsequent chemical modification in living culture can be achieved. This approach can potentially enable many new applications: for example, assay of directed evolution of enzymes catalyzing halo-metabolite biosynthesis in living cells or generating and following the fate of tagged metabolites and biomolecules in living systems. We report synthetic biological access to new-to-nature bromo-metabolites and the concomitant biorthogonal cross-coupling of halo-metabolites in living cultures.Coupling synthetic biology and chemical reactions in cells is a challenging task. The authors engineer bacteria capable of generating bromo-metabolites, develop a mild Suzuki-Miyaura cross-coupling reaction compatible with cell growth and carry out the cross-coupling chemistry in live cell cultures.

The palladium-catalysed aqueous α-arylation of ketones was developed and tested for a large variety of reaction partners. These mild conditions enabled the coupling of aryl/alkyl-ketones with N-protected halotryptophans, heterocyclic haloarenes, and challenging base-sensitive compounds. The synthetic potential of this new methodology for the diversification of complex bioactive molecules was exemplified by derivatising prochlorperazine. The methodology is mild, aqueous and flexible, representing a means of functionalizing a wide range of halo-aromatics and therefore has the potential to be extended to complex molecule diversification., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A palladium N-heterocyclic carbene catalyzed methodology for the synthesis of substituted, N-unprotected indoles and azaindoles is reported. The protocol permits access to various, highly substituted members of these classes of compounds. Although two possible reaction pathways (deprotonative and Heck-like) can be proposed, control experiments, supported by computational studies, point toward a deprotonative mechanism being operative., Competing Interests: The authors declare no competing financial interest.

The first nickel catalyzed deprotonative cross coupling between C(sp 3 )-H bonds and aryl chlorides is reported, allowing the challenging arylation of benzylimines in the absence of directing group or stoichiometric metal activation. This methodology represents a convenient access to the (diarylmethyl)amine moiety, which is widespread in pharmaceutically relevant compounds.

Layered copper-nickel cyanide, CuNi(CN)4, a 2-D negative thermal expansion material, is one of a series of copper(ii)-containing cyanides derived from Ni(CN)2. In CuNi(CN)4, unlike in Ni(CN)2, the cyanide groups are ordered generating square-planar Ni(CN)4 and Cu(NC)4 units. The adoption of square-planar geometry by Cu(ii) in an extended solid is very unusual.

A general methodology for the α-arylation of ketones using a nickel catalyst has been developed. The new well-defined [Ni(IPr*)(cin)Cl] (1 c) pre-catalyst showed great efficiency for this transformation, allowing the coupling of a wide range of ketones, including acetophenone derivatives, with various functionalised aryl chlorides. This cinnamyl-based Ni-N-heterocyclic carbene (NHC) complex has demonstrated a different behaviour to previously reported NHC-Ni catalysts. Preliminary mechanistic studies suggest a Ni(0)/Ni(II) catalytic cycle to be at play., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A general catalytic protocol for the α-arylation of aryl ketones has been developed. It involves the use of a preformed, bench-stable Pd-N-heterocyclic carbene pre-catalyst bearing IHept as an ancillary ligand, and allows the coupling of various functionalized coupling partners at very low catalyst loading. Careful choice of the solvent/base system was crucial to obtain optimum catalyst performance. The pre-catalyst was also successfully tested in the synthesis of an industrially relevant compound., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A nickel/N-heterocyclic carbene (NHC) catalysed carboxylation of aryl-, heteroaryl- and alkenylboronates, affording the corresponding carboxylic acids, has been developed. This transformation proceeds under one atmosphere of CO2 with a broad range of substrates and exhibits good functional group compatibility.

Neutron diffraction at 11.4 and 295 K and solid-state (67)Zn NMR are used to determine both the local and the average structures in the disordered, negative thermal expansion (NTE) material, Zn(CN)2. Solid-state NMR not only confirms that there is head-to-tail disorder of the C≡N groups present in the solid, but yields information about the relative abundances of the different Zn(CN)4–n(NC)n tetrahedral species, which do not follow a simple binomial distribution. The Zn(CN)4 and Zn(NC)4 species occur with much lower probabilities than are predicted by binomial theory, supporting the conclusion that they are of higher energy than the other local arrangements. The lowest energy arrangement is Zn(CN)2(NC)2. The use of total neutron diffraction at 11.4 K, with analysis of both the Bragg diffraction and the derived total correlation function, yields the first experimental determination of the individual Zn–N and Zn–C bond lengths as 1.969(2) and 2.030(2) Å, respectively. The very small difference in bond lengths, of ~0.06 Å, means that it is impossible to obtain these bond lengths using Bragg diffraction in isolation. Total neutron diffraction also provides information on both the average and the local atomic displacements responsible for NTE in Zn(CN)2. The principal motions giving rise to NTE are shown to be those in which the carbon and nitrogen atoms within individual Zn–C≡N–Zn linkages are displaced to the same side of the Zn···Zn axis. Displacements of the carbon and nitrogen atoms to opposite sides of the Zn···Zn axis, suggested previously in X-ray studies as being responsible for NTE behavior, in fact make negligible contributions at temperatures up to 295 K.

Binary mixed-metal variants of the one-dimensional MCN compounds (M = Cu, Ag, and Au) have been prepared and characterized using powder X-ray diffraction, vibrational spectroscopy, and total neutron diffraction. A solid solution with the AgCN structure exists in the (Cu(x)Ag(1-x))CN system over the range (0 ≤ x ≤ 1). Line phases with compositions (Cu(1/2)Au(1/2))CN, (Cu(7/12)Au(5/12))CN, (Cu(2/3)Au(1/3))CN, and (Ag(1/2)Au(1/2))CN, all of which have the AuCN structure, are found in the gold-containing systems. Infrared and Raman spectroscopies show that complete ordering of the type [M-C≡N-M'-N≡C-](n) occurs only in (Cu(1/2)Au(1/2))CN and (Ag(1/2)Au(1/2))CN. The sense of the cyanide bonding was determined by total neutron diffraction to be [Ag-NC-Au-CN-](n) in (Ag(1/2)Au(1/2))CN and [Cu-NC-Au-CN-](n) in (Cu(1/2)Au(1/2))CN. In contrast, in (Cu(0.50)Ag(0.50))CN, metal ordering is incomplete, and strict alternation of metals does not occur. However, there is a distinct preference (85%) for the N end of the cyanide ligand to be bonded to copper and for Ag-CN-Cu links to predominate. Contrary to expectation, aurophilic bonding does not appear to be the controlling factor which leads to (Cu(1/2)Au(1/2))CN and (Ag(1/2)Au(1/2))CN adopting the AuCN structure. The diffuse reflectance, photoluminescence, and 1-D negative thermal expansion (NTE) behaviors of all three systems are reported and compared with those of the parent cyanide compounds. The photophysical properties are strongly influenced both by the composition of the individual chains and by how such chains pack together. The NTE behavior is also controlled by structure type: the gold-containing mixed-metal cyanides with the AuCN structure show the smallest contraction along the chain length on heating.

Analysis and modeling of X-ray and neutron Bragg and total diffraction data show that the compounds referred to in the literature as "Pd(CN)(2)" and "Pt(CN)(2)" are nanocrystalline materials containing small sheets of vertex-sharing square-planar M(CN)(4) units, layered in a disordered manner with an intersheet separation of ~3.44 Å at 300 K. The small size of the crystallites means that the sheets' edges form a significant fraction of each material. The Pd(CN)(2) nanocrystallites studied using total neutron diffraction are terminated by water and the Pt(CN)(2) nanocrystallites by ammonia, in place of half of the terminal cyanide groups, thus maintaining charge neutrality. The neutron samples contain sheets of approximate dimensions 30 Å × 30 Å. For sheets of the size we describe, our structural models predict compositions of Pd(CN)(2)·xH(2)O and Pt(CN)(2)·yNH(3) (x ≈ y ≈ 0.29). These values are in good agreement with those obtained from total neutron diffraction and thermal analysis, and are also supported by infrared and Raman spectroscopy measurements. It is also possible to prepare related compounds Pd(CN)(2)·pNH(3) and Pt(CN)(2)·qH(2)O, in which the terminating groups are exchanged. Additional samples showing sheet sizes in the range ~10 Å × 10 Å (y ~ 0.67) to ~80 Å × 80 Å (p = q ~ 0.12), as determined by X-ray diffraction, have been prepared. The related mixed-metal phase, Pd(1/2)Pt(1/2)(CN)(2)·qH(2)O (q ~ 0.50), is also nanocrystalline (sheet size ~15 Å × 15 Å). In all cases, the interiors of the sheets are isostructural with those found in Ni(CN)(2). Removal of the final traces of water or ammonia by heating results in decomposition of the compounds to Pd and Pt metal, or in the case of the mixed-metal cyanide, the alloy, Pd(1/2)Pt(1/2), making it impossible to prepare the simple cyanides, Pd(CN)(2), Pt(CN)(2), or Pd(1/2)Pt(1/2)(CN)(2), by this method.

Two patients presented with the cardinal symptoms of Parkinson's disease (PD), which had developed slowly and progressively. One patient underwent brain imaging of the dopaminergic system, the results of which were compatible with PD. However, both patients showed no response to L-dopa or oral dopaminergic medication. They also had optic nerve atrophy of unknown etiology. The severe motor symptoms of both patients were conspicuously alleviated by apomorphine delivered subcutaneously. One patient underwent bilateral subthalamic nucleus deep brain stimulation, which also proved effective., ((c) 2006 Movement Disorder Society.)