1,846 research outputs found
cis-Dichloridobis(dimethoxyphenylphosphine)palladium(II)
The title compound, [PdCl2(C8H11O2P)2], has a comparable structure to those of related palladium dichloride complexes containing trimethyl phosphinite and methyl diphenyl phosphinite. The Pd atom is located on a crystallographic twofold rotation axis: thus, there is just one half-molecule in the asymmetric unit. The structure is isomorphous with the platinum analogue cis-[PtCl2{P(OMe)2Ph}2]
OrganiZational communication and organiSational communication: Binaries and the fragments of a field
In this paper, I employ personal narrative to help cast light on connections and tensions between organiZational communication research, as produced in the United States, and organiSational communication research, as produced in Aotearoa New Zealand. I address the issue by highlighting three sets of differences between these bodies of research: canonical, institutional and theoretical. I then unpack how these differences are apparent in my own university before sketching out three ways in which we might productively use such tensions to achieve radical engagement, and critique disciplinary others, identities, and locations
Bis(μ-disulfur dinitrido)bis[diphenyltin(IV)]
The title compound, [Sn2(C6H5)4(N2S2)2], exists as a centrosymmetric binuclear dimer with the SnIV centres in distorted trigonal bipyramidal geometry and a central Sn2N2 core
cis-Dichloridobis(triisopropoxyphosphine)platinum(II)
The title compound, [PtCl2(C9H21O3P)2], was obtained from a solution of PtCl2(COD) (COD = 1,5-cyclooctadiene) and triisopropylphosphite in dichloromethane. The complex features a Pt(II) atom coordinated by two Cl and two P atoms, yielding a slightly distorted cis square-planar geometry
The remarkable effect of the 7-substituent in the diastereoselective oxidative rearrangement of indoles: Asymmetric synthesis of 3,3-disubstituted oxindoles
International audienceThe nature of the 7-substituent has a remarkable effect on the diastereoselectivity of the oxidative rearrangement of indole-2- carboxamides derived from (S)-2-methoxymethylpyrrolidine into chiral 3,3-disubstituted oxindoles
rel-(1R,4S,5S,8R)-1,4:5,8-Diepoxy-1,4,5,8-tetrahydroanthracene: an example of polymorphism
From biomass to the karrikins via selective catalytic oxidation of hemicellulose-derived butyl xylosides and glucosides
Funding: This work was supported by a China Scholarship Council-University of St Andrews PhD Fellowship (GX) and an IBioIC funded PhD studentship in collaboration with Scottish Forestry and the Scottish Forestry Trust (GS).Members of the karrikin family of bioactive small molecules are known to promote germination of a range of plants following large scale fires. As a result, they are relevant and interesting compounds. This report describes their synthesis from a biomass-derived product stream. During work to fractionate biomass with the goal of obtaining high quality lignins, an interesting co-product stream derived from the hemicellulose in the biomass, was obtained. Whilst many applications of this co-product stream can be proposed, in this case the major monosaccharides have been converted to relevant karrikins in short reaction sequences. Key results include a highly selective catalytic oxidation reaction, conversion of the resulting ketone to a butenolide by two alternative approaches, a selective acetal reductive opening reaction, X-ray crystallographic analysis of two compounds and detailed comparison of the final products with previous literature reports. Only through successful use of all the components generated during biomass refining, can economic sustainability be potentially achieved.Publisher PDFPeer reviewe
Kinetic Resolution in Asymmetric Epoxidation using Iminium Salt Catalysis
The first reported examples of kinetic resolution in epoxidation reactions using iminium salt catalysis are described, providing up to 99% ee in the epoxidation of racemic cis-chromenes
Bis(phenylphosphonic) anhydride
The asymmetric unit of the title compound, C12H12O5P2, contains four independent molecules, generating two dimers via pairs of intermolecular O—H⋯O hydrogen bonds, forming R
2
2(8) rings. The two aryl rings of each molecule form dihedral angles of 108.6 (1), 103.2 (1), 12.5 (2) and 8.1 (2)° in the four molecules
Sterically restricted tin phosphines, stabilized by weak intramolecular donor-acceptor interactions
Funding: Engineering and Physical Sciences Research Council (EPSRC)Four related sterically restricted pen-substituted acenaphthenes have been prepared containing mixed tin phosphorus moieties in the proximal 5,6-positions (Acenap[SnR3][(PPr2)-Pr-i]; Acenap = acenaphthene-5,6-diyl; R-3 = Ph-3 (1), Ph2Cl (2), Me2Cl (3), Bu2Cl (4)). The degree of intramolecular P-Sn bonding within the series was investigated by X-ray crystallography, solution and solid-state NMR spectroscopy, and density functional theory (DFT/B3LYP/SBKJC/PCM) calculations. All members of the series adopt a conformation such that the phosphorus lone pair is located directly opposite the tin center, promoting an intramolecular donor acceptor P -> Sn type interaction. The extent of covalent bonding between Sn and P is found to be much greater in triorganotin chlorides 2-4 in comparison with the triphenyl derivative 1. Coordination of a highly electronegative chlorine atom naturally increases the Lewis acidity of the tin center, enhancing the Ip(P)-sigma*(Sn-Y) donor acceptor 3c-4e type interaction, as indicated by conspicuously short Sn-P peri distances and significant (1)J(P-31,Sn-119) spin spin coupling constants (SSCCs) in the range 740-754 Hz. Evidence supporting the presence of this interaction was also found in solid-state NMR spectra of some of the compounds which exhibit an indirect spin spin coupling on the same order of magnitude as observed in solution. DFT calculations confirm the increased covalent bonding between P and Sn in 2-4, with notable WBIs of ca. 0.35 obtained, in comparison to 0.1 in 1.PostprintPeer reviewe
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