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Recent advances in cooperative chemistry have shown the potential of heterobimetallic complexes combining an alkali-metal with an earth abundant divalent transition metal for the functionalisation of synthetically relevant aromatic molecules via deprotonative metalation. Pairing sodium with cobalt (II), here we provide an overview of the reactivity of bimetallic [NaCo(HMDS)3] [HMDS = N(SiMe3)2] towards C-H and C-F functionalisation of a wide range of perfluorinated molecules. These studies also uncover the enormous potential of this heterobimetallic base to perform Co-H exchanges with excellent selectivity and exceptional stoichiometric control as well as shedding light on the key role played by the alkali-metal.

Recent advances in cooperative chemistry have shown the enormous potential of main group heterobimetallic complexes for the functionalisation of aromatic molecules. Going beyond main group metal chemistry, here we provide an overview on the synthesis, structure and reactivity of bimetallic complexes which combine an alkali-metal (AM= Li, Na) with a divalent earth-abundant transition metal (M= Mn, Fe, Co, Ni), containing the utility silyl amide HMDS (HMDS = N(SiMe3)2). Advancing the understanding on how cooperative effects operate in these bimetallic (ate) systems, selected examples of their applications in deprotonative metalation are also discussed with special emphasis on the constitution of the metalated intermediates.

The reaction of phenyldichlorophosphane, PhPCl2, a commercially important precursor for organophosphorus compounds, with lithium and sodium as reducing metals was re-investigated with the aim to well-characterize the resulting oligophosphandiides, [M2(PnPhn)(solv)x] (M = Li, Na). Experimental conditions for the optimal formation of these compounds were found for both series with M = Li and M = Na and several of these were crystallized and characterized by X-ray diffraction studies. As a result, we find that sodium strongly prefers ion triple structures [M2(PnPhn)(solv)x] over solvent-separated ion pairs, [M(solv)m]+[MPnPhn(solv)n]?, which have a higher tendency to form with M = Li. Also, while [Na2(P4Ph4)(solv)x] retains its structure in thf solution, [Li2(P4Ph4)(solv)x] partially dissociates into the radical anion (Ph2P2).? which is detected by EPR spectroscopy. The knowledge about the structures and the behavior of the alkali metal diphosphandiides allows us to propose a reaction mechanism for their formation.

Abstract: Objective: Assessment of haemodynamic, respiratory and renal effects of hypertonic saline–hydroxyethyl starch (HyperHES®) in critically ill-patients with hemorrhagic shock. Patients and methods: Seventeen mechanically ventilated patients with hemorragic shock benefiting from a cardiovascular monitoring by PiCCO device and requiring rapid volume loading. Two hundred and fifty milliliters of HyperHES® were given over 5minutes. The efficacy of volume loading was assessed by the measure of the systolic arterial pressure (SAP), cardiac index (CI), stroke volume variation (SVV) and the indexed systemic vascular resistance (iSVR). Studied parameters were assessed at baseline, 5, 30, 60 and 180minutes after the end of HyperHES® infusion. Results: SAP (105±23 vs 77±10; p <0.001) and CI (4.8±1.1 vs 3.5±0.9; p <0.001) were significantly increased whereas iSVR (1175±310 vs 1501±337; p <0.01) and SVV (13±7 vs 20±5; p <0.01) were significantly decreased 5minutes after the HyperHES® infusion. Sodium (145±6 vs 136±5; p <0.001) and chloride (118±7 vs 107±6; p <0.001) were increased 5minutes after the infusion. The PaO2/FiO2 ratio as the extravascular lung water was not influenced by the infusion. The follow-up of renal parameters during the three first days (creatinemia, uremia and diuresis) did not revelead significant variations. Conclusion: In patients with hemorrhagic shock, the infusion of hypertonic saline (7.5%) hydroxyethyl starch association was followed by an increase in SAP, CI serum sodium and chloride concentrations. Study design: Prospective observational study. [Copyright &y& Elsevier]

Abstract: Two per cent of the world population suffers from bipolar trouble that can be improved by thymoregulators. In France this corresponds to 800,000 adult patients, however in France prescriptions of thymoregulators represent only a third of this number and prescriptions of lithium are made for only 80,000 patients. What is the reason of this peculiarity? [Copyright &y& Elsevier]

Graphite intercalation compounds: from binaries to ternaries. Graphite, which is an amphoteric host structure, easily reacts with electropositive elements and especially with alkali metals, leading to binary graphite–metal intercalation compounds. Alkali metals can also help elements unable to react alone with graphite to intercalate. Therefore, ternary intercalation compounds are obtained using various synthesis routes. To cite this article: C. Herold, P. Lagrange, C. R. Chimie 6 (2003). [Copyright &y& Elsevier]

This contribution gives an overview on the different subjects treated in our group during the last four years. First, the concept of cutting out structural fragments from a solid-state structure will be explained on behalf of BaI2. Oxygen donor ligands, used as chemical scissors on BaI2, enabled three-, two-, one- and zero-dimensional derived compounds to be obtained depending on their size and concentration. Thus, a structural genealogy tree for BaI2 can be established. A second section deals with the supramolecular approach for the synthesis of different dimensional polymer structures derived from alkaline earth metal iodides, and based on the combination of metal ion coordination with hydrogen bonding between the cationic complexes and their anions. Under certain circumstances, rules can be established for the prediction of the dimensionality of a given compound, thus contributing to the problem of structure prediction in crystal engineering. A third part describes a new synthetic pathway for generating homometallic alkaline earth metal clusters as well as group 1 and 2 mixed metal clusters as potential precursors for oxide materials. Finally, some physical properties of these compounds are described qualitatively in order to show the wide spectrum of possibilities and potential applications for the chemistry in this field.

A new application of electrolysis for the dechlorination of copper alloys has been developed. Electrolytic treatment with weak polarization in sodium sesquicarbonate permits the extraction of the chlorides and the preservation of the stable alteration products. It is more effective and less time-consuming than chemical methods. The method has been applied successfully to archaeological objects from both marine and land sites. [ABSTRACT FROM AUTHOR]

Tripotassium triiron(III) tetraarsenate, K3Fe3(AsO4)4, has been synthesized at high temperature by solid-state reaction. The structure is built up from corner- and edge-sharing between FeO6 octahedra and AsO4 tetrahedra. The structure can be described as infinite anionic layers parallel to the (010) plane. Alkali metal cations are located in the interlayer space. The relationship between the title compound and K3Fe3(PO4)4·H2O structures is discussed. The title compound is isostructural with K3Cr3(AsO4)4. [ABSTRACT FROM AUTHOR]

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