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A platinum(II) polyyne/diketopyrrolopyrole-containing polymer of two different chain lengths, P (short) and P' (long chain), were prepared in order to elucidate the reasons for the poor photoconversion efficiencies (PCEs) in bulk heterojunction solar cells recently reported in the Journal of Organometallic Chemistry (2019), 894, 1–9, whereas other solar cells using similar platinum(II) polyyne/diketopyrrolopyrole-containing polymers provided significantly better PCEs. Using thermodynamic arguments using electrochemical and spectroscopy data, quenching experiments of the fluorescence band of P using fullerene (PC61BM and PC71BM) nonfullerene (MCzM) acceptors, and testing photochemical stability of P and P', three possible reasons were found. These reasons are the undetected photochemical instability of similar polymers used by Wong, and the likely inappropriate choice of electron acceptor (PC61BM) in this past investigation. [ABSTRACT FROM AUTHOR]

In this work, a new 3D crystalline metal-organic framework formulated as [Zn(BTC), (BTC: 1,2,4,5-Benzenetetracarboxylate)] and called LCP-1 (LCP: Laboratoire de Chimie des Polymères), with unsaturated coordinated Zn(II) sites as metal ion and pyromellitic acid (HBTC: 1,2,4,5-Benzenetetracarboxylic acid) as organic ligand, has been successfully synthesized under solvothermal conditions. In-Situ polymerization of this material was also carried out using an amount of clay called Maghnite-H, an acid-exchanged montmorillonite, as an eco-catalyst with the aim to respect the principles of green chemistry, to give a new hybrid composite material LCP-1/Mag-H with a better yield, a significantly reduced time and temperature reaction than those of LCP-1. LCP-1 and LCP-1/Mag-H have been structurally characterized and established by fourier transform infrared spectroscopy (FT-IR). The morphology of these compounds was studied by the X-ray diffraction (XRD) and revealed a highly crystalline and ordered structure for both LCP-1 and LCP-1/Mag-H. FT-IR and XRD spectra showed also that the stability and structural integrity of LCP-1 and LCP-1/Mag-H was maintained even after being evacuated from the DMF solvent molecules. The thermal stability identified by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) showed that Maghnite-H, as inorganic support, has also improved the thermal stability of LCP-1 compound. [ABSTRACT FROM AUTHOR]

High pressure Raman scattering on Mo(CO) up to 37.7 GPa at ambient temperatures are recorded inside the Diamond-Anvil-Cell (DAC). The Raman spectra of the molybdenum hexacarbonyl completely vanish at 23.3 GPa, signifying novel pressure induced decomposition. The decomposed Raman spectrum recovered at ambient conditions has the characteristic features of a highly dense polymer with δ(OCO) units possibly attached to metal centers, C=O functional group, and graphitic carbon; and also CO adsorbed to molybdenum metal centres. The so formed highly dense metal mediated polymer upon relaxation from high pressure conditions and upon exposure to 514.5 nm argon ion laser outside the DAC transforms to MoO in the presence of disordered carbon as characterized by the Raman modes. [ABSTRACT FROM AUTHOR]

The synthesis of terpyridine-based polyimide catalysis for hydrosilylation reaction is outlined in this work. 5,5′′-Bis(bromomethyl)-2,2′:6′,2′′-terpyridine was polymerized with the corresponding diimide derivatives of dianhyrides to give polyimides utilizing the terpyridine unit in the main chain. The synthesis of polyimides containing Ru(II) complexes in the side chain is described. Condensation polymerization is used to synthesize the macromolecular backbone and, as a result, the Ru(II) complex was attached via coordination chemistry. The material design emphasizes the relationship between the molecular structure and supramolecular organization of these polymers. It demonstrates that terpyridyl complexes remain a versatile functionality for constructing supramolecular assemblies. The terpyridine unit may enhance the electron carrier mobility of the polymers, while the incorporation of ruthenium complexes into a conjugated polymer significantly changes the catalytic properties of the resulting polymers. The prepared polyimide-supported catalyst provides superior catalytic activity (70-79%), selectivity and stability in the hydrosilylation of acetophenone. The catalyst can be easily isolated from the reaction product, which benefits recycling. The catalysts were reused for four experiments. [ABSTRACT FROM AUTHOR]

group of hyperbranched poly(silylenearylene)s are synthesized by homopolycyclotrimerizations of A-type silylenediynes. The polymers can be readily metallized by complexations of their periphery triple bonds with cobalt octacarbonyls Co(CO). Pyrolysis of these organometallic polymers gives magnetic ceramics in good yields. Analyses by SEM, TEM, XPS, EDX, and XRD demonstrate that the ceramics comprise ferromagnetic Co and paramagnetic CoSi nanocrystallites wrapped by carboneous shell. The ceramics show high magnetic susceptibilities ( M up to ~50 emu/g) and near-zero coercivity ( H down to ~0.14 kOe), suggesting that they are good soft magnetic materials with low hysteresis loss. [ABSTRACT FROM AUTHOR]

The reaction of bis( para-ethynylbenzene)-2,3,5,6-tetramethoxyquinone diimine and bis( para-ethynylbenzene)-2,3,5,6-tetramethoxyquinone diamine and trans-Pt(PEt)Cl in a 1:1:2 ratio in the presence of CuI and iPrNH generates the polydispersed material poly(bis( para-ethynylbenzene)-2,3,5,6-tetramethoxy-quinone diimine)- trans-bis(triethyl-phosphine)platinum(II)-(bis( para-ethynylbenzene)-2,3,5, 6-tetramethoxyquinone diamine)- trans-bis(triethylphosphine)platinum(II). Based on the luminescence decay traces, the distribution of the diimine and diamine residues is statistic. [ABSTRACT FROM AUTHOR]

ClPd(μ-dppm)PtCl ( 1) reacts with (CNCH-2-OCH-) to form a sparingly soluble and thermally stable orange polymeric material 4. 1 reacts with 1 or 2 equivalents of CNCH-2-OCH to form the soluble A-frame d-d model complexes 2 [ClPd(μ-dppm)(μ-CNR)PtCl], and 3 [ClPd(μ-dppm)(μ-CNR)Pt(CNR)](Cl) (R = CH-2-OCH), respectively. IR (ν(NC) bridging versus terminal) and NMR data reveal an A-frame structure where the terminal CNR ligands are bonded to Pt. 4 which is amorphous (XRD) appears stable up to 290 °C (TGA), but exhibits an exothermic process between 215 and 255 °C upon the first scan in DSC, but disappears upon the second. Two compounds, model 2 (λ = 674 nm; τ = 0.38 ± 0.01 μs; Φ = 0.0079 (±10%)) and polymer 4 (λ = 660 nm; τ = 0.18 ± 0.01 μs; Φ = 0.0056 (±10%)) are luminescent at 77 K in the solid state and in fluid solution (PrCN). Graphical abstract: The First A-Frame-Containing Organometallic Polymer: Taking Advantage of the Site Selectivity in PdPt-Mixed Metal Bimetallics Sébastien Clément, Shawkat Mohammed Aly, Karl Gagnon, Alaa S. Abd-El-Aziz, Michael Knorr, Pierre D. Harvey ClPd(μ-dppm)Cl reacts with (CN-CH-O-CH-) to form the first A-frame-containing organometallic polymer, which is unambiguously characterized with the use of model compounds. This polymer does not experience any weight loss up to 290 °C based on TGA measurements, but DSC traces reveal an irreversible process at 215 °C (DSC). The novel material is also luminescent at 77 K. For example, λ = 660 nm; τ = 0.18 ± 0.01 μs; Φ = 0.0056 (±10%) in PrCN. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

The interaction of the Hg(II) derivatives bis(pentafluoro)phenyl mercury ( 1), (pentafluoro)phenyl mercury chloride ( 2) and trimeric perfluoro- ortho-phenylene mercury ( 3) with tolane (diphenylacetylene) in CHCl leads to the formation of [ 1·tolane], [ 2 ·tolane], and [ 3·tolane·CHCl]. These adducts have been characterized by elemental analysis, X-ray crystallography, and luminescence spectroscopy. In the solid state of these adducts, the tolane molecules interact with the molecules of 1, 2 and 3 via secondary Hg-π interactions and arene-fluoroarene interactions. As a result of an external mercury heavy atom effect, adducts [ 1·tolane] and [ 2 ·tolane] are phosphorescent at room temperature. [ABSTRACT FROM AUTHOR]

The wide range of applications for the phosphazene compounds has stimulated a major research effort involving several industrial, academic, and national laboratories over the past 40 years. One of Professor Allen's research areas was to establish fundamental synthetic methods for the commercial preparation of phosphazene polymers, investigate their properties, and develop useful products. In this paper we review some of the materials science aspects of Professor Allen's research including recent advances on the preparation and polymerization of ClPNP(O)Cl. This work, in particular, has led to a route for the 'one-pot' synthesis of stable linear poly(organophosphazenes) as demonstrated through the formation of poly[ bis-(2-methoxyethoxyethoxy)phosphazene] (MEEP) and a phosphazene heteropolymer (HPP) containing a balance of hydrophilic and hydrophobic components that allow for control and molecular affinities. [ABSTRACT FROM AUTHOR]

A biography of Professor Didier Astruc, distinguished professor, researcher and a pioneer in the fields of organometallic electron-transfer processes, is presented. Astruc was born in Versailles, France on June 9, 1946. He achieved his doctoral degree on ferrocene-cage complexes under Professor R. Dabard in Rennes. Astruc was responsible for the concept of organometallic "Electron Reservoirs." His other works include the first peralkylation of polyalkylarenes, and the integration of inorganic and dendritic aspects in materials sciences.