Crystal structure and identification of resonance forms of diethyl 2-(3-oxoiso-1,3-dihydrobenzofuran-1-ylidene)malonate

The research leading to these results received funding from the European Community's Seventh Framework Programme ([FP7/2007–2013]) under grant agreement No. 607411 (MC-ITN EREAN: European Rare Earth Magnet Recycling Network).The reaction of diethyl malonate with phthaloyl chloride in acetonitrile in the presence of triethylamine and magnesium chloride results in the formation of the title compound, diethyl 2-(3-oxo-1,3-dihydro-2-benzofuran-1-ylidene)propanedioate, C15H14O6. One of the ester groups of the diethyl malonate fragment is almost coplanar with the isobenzofuran unit, while the plane of the other group is perpendicular to it [dihedral angles = 5.45(3) and 83.30(3)°, respectively]. The C—C and C—O distances both in the heterocyclic furan ring and the diethyl malonate fragment are indicative of the dipolar delocalization occurring within the isobenzofuran unit. This delocalization is likely to be responsible for the unusual intermolecular O···O contact [2.756(2)Å], established between the O atom of the furan ring and the carbonyl O atom of the diethyl malonate fragment. In the crystal, weak C—H···O interactions are observed, which link the molecules into [100] chains.Publisher PDFPeer reviewe

Identification of the chemical inventory of different paint types applied in nuclear facilities

The floors, concrete walls and many of the metal surfaces in nuclear power plant containments are coated with zinc primers or paint films to preserve the metal surfaces and simplify decontamination in the containment after the occurrence of a severe nuclear incident or accident. A chemical examination of paint films from different nuclear installations out of operation, as well as current operating ones, reveals that different types of paints are used whose composition can vary significantly. Results obtained for one type of paint at a certain nuclear site are in most cases unlikely to be comparable with sites painted with another type of paint. During normal operation and particularly during nuclear accidents, the paints will degrade under the high temperature, steam and irradiation influence. As paint and its degradation products can act as sources and depots for volatile iodine compounds, the type and aging conditions of the paint films will have a significant impact on the source term of the volatile fission product iodine. Thus, great care should be taken when extrapolating any results obtained for the interaction of radioactive iodine with one paint product to a different paint product. The main focus of the study is a comparison of the chemical profile of paint films applied in Swedish nuclear power plants. Teknopox Aqua V A, an epoxy paint recently used at Ringhals 2, and an emulsion paint used in the scrubber buildings of Ringhals 1-4 are compared with a paint film from Barseback nuclear power plant unit 1 that had been aged under real reactor conditions for 20 years. In addition, two paint films, an emulsion and a gloss paint, used in an international nuclear fuel reprocessing facility, are compared with the paints from the Swedish nuclear power plants

Crystal structure and identification of resonance forms of diethyl 2-(3-oxoiso-1,3-dihydrobenzofuran-1-ylidene)malonate

The reaction of diethyl malonate with phthaloyl chloride in acetonitrile in the presence of triethylamine and magnesium chloride results in the formation of the title compound, diethyl 2-(3-oxo-1,3-dihydro-2-benzofuran-1-ylidene)propanedioate, C15H14O6. One of the ester groups of the diethyl malonate fragment is almost coplanar with the isobenzofuran unit, while the plane of the other group is perpendicular to it [dihedral angles = 5.45(3) and 83.30(3)°, respectively]. The C—C and C—O distances both in the heterocyclic furan ring and the diethyl malonate fragment are indicative of the dipolar delocalization occurring within the isobenzofuran unit. This delocalization is likely to be responsible for the unusual intermolecular O···O contact [2.756(2)Å], established between the O atom of the furan ring and the carbonyl O atom of the diethyl malonate fragment. In the crystal, weak C—H···O interactions are observed, which link the molecules into [100] chains

A comparison on the use of DEHBA or TBP as extracting agent for tetra- and hexavalent actinides in the CHALMEX Process

The Chalmers Grouped ActiNide EXtraction process is a solvent extraction process for the homogeneous recycling of spentnuclear fuel. The use of TBP for the extraction of tetra- and hexavalent actinides can be problematic for several reasons,including troublesome degradation products causing crud formation, decreased extraction yield and the possibility of explosivered oil reactions. Here, the substitution of TBP by a N,N-dialkyl monoamide, DEHBA, is investigated. The findingssuggest that DEHBA can be a suitable extracting agent for use in the CHALMEX solvent, although identified drawbacksneed to be further investigated

One-dimensional and two-dimensional coordination polymers constructed from Cd2+ ions and flexible bipyridyl bridging ligands

Acknowledgements We thank the EPSRC National Crystallography Service (University of Southampton) for the X-ray data collections and the EPSRC National Mass Spectrometry Service (University of Swansea) for the high-resolution mass spectra data.Peer reviewedPostprin

Coordination networks of Cu2+ ions with 1,3-bis[2-(4-pyridyl)ethyl]benzene : strong structure-directing role of the counter ion (nitrate, acetate and sulphate), leading to clusters, sheets and chains

Date of Acceptance: 16/10/2015 Acknowledgements We thank the EPSRC National Mass Spectrometry Facility (University of Swansea) for the high-resolution mass spectrometry data and the EPSRC National Crystallography Service (University of Southampton) for the X-ray data collections and preliminary structural analyses.Peer reviewedPostprin

Crystal structure of a layered coordination polymer based on a 44 net containing Cd2+ ions and 1,5-bis(pyridin-4-yl)pentane linkers

The title compound, poly[[diaquabis[1,5-bis(pyridin-4-yl)pentane-κ2N:N′]cadmium] bis(perchlorate) 1,5-bis(pyridin-4-yl)pentane ethanol monosolvate], [Cd(C15H18N2)2(H2O)2](ClO4)2·C15H18N2·C2H6O, is a layered coordination polymer built up from highly squashed 44 nets in which the octahedral trans-CdO2N4 nodes (Cd site symmetry -1) are linked by the bifunctional ligands, forming infinite (110) sheets. The cationic sheets are charge-balanced by interlayer perchlorate ions. A free 1,5-bis(pyridin-4-yl)pentane molecule and an ethanol molecule of crystallization are also found in the intersheet region. A number of O—H...O, O—H...N and C—H...O hydrogen bonds help to consolidate the layered structure

Coordination of trivalent lanthanides with bismalonamide ligands:implications for liquid-liquid extraction

The complexation of the bismalonamide ligand 2,2'-(1,2-phenylenebis(methylene))bis(N,N,N',N'-tetraethylmalonamide) (L), bearing two C-alkylated N,N,N',N'-tetraethylmalonamide groups onto ortho-xylylene (C6H4(CH2)2) platform, with trivalent lanthanides was investigated both in solid- and solution states. The crystal structures [Nd2(NO3)6L2]·(CH3CN)3 (2), [Nd2(NO3)4L2]·[Nd(NO3)5]·(CH3CN)1.5 (3), Ce(NO3)3L2 (4) and [NdL2]·(ClO4)3·C2H5OH (5) were analyzed by single-crystal X-ray diffraction. The ortho-bismalonamide (L) is tetradentate in the structures 2, 3 and 5 and bidentate in 4 only. It was found that the structures 2 and 3 are composed of dimeric species. According to electrospray ionization - mass spectrometry the dimers are prevailing in acetonitrile solutions. The polydentate coordination of the ortho-bismalonamide (L) with trivalent lanthanides suggests that an entropy effect favors liquid-liquid extraction of the metal ions with this type of ligands