TY - JOUR A1 - Riddell, N. A1 - Becker, Roland A1 - Chittim, B. A1 - Emmerling, Franziska A1 - Köppen, Robert A1 - Lough, A. A1 - McAlees, A. A1 - McCrindle, R. T1 - Preparation and X-ray structural characterization of further stereoisomers of 1,2,5,6,9,10-hexabromocyclododecane N2 - Technical 1,2,5,6,9,10-hexabromocyclododecane (HBCD) consists largely of three diastereomers (α-, β-, and γ-HBCD) produced by the trans addition of bromine to cis,trans,trans-cyclododeca-1,5,9-triene (CDT). However, another seven diastereomers are theoretically possible and may be produced by trans addition of bromine across the double bonds of the other three isomers of 1,5,9-CDT. There are indications that small amounts of the minor HBCD isomers may be present in commercial HBCD mixtures or in products containing this brominated flame retardant (BFR). Such minor components may indeed derive from traces of other 1,5,9-CDTs in the cis, trans, trans starting material, however their formation may also be possible through isomerizations during the processing of this BFR or by bioisomerization subsequent to its release into the environment. Two of the seven additional diastereomers (δ- and ε-HBCD) were synthesized previously from trans,trans,trans-CDT. We now report the preparation of the remaining five diastereomers, ζ-, η-, and θ-HBCD from cis,cis,trans-CDT and ι- and κ-HBCD from cis,cis,cis-CDT, and their characterization by 1H NMR spectroscopy and X-ray crystallography. The availability of these further diastereomers of HBCD should aid in determining if the minor isomers are present in commercial samples of this BFR, in products containing HBCDs, or in environmental samples. We have also carried out an X-ray crystal structure determination on ε-HBCD, so that crystal structures are now available for all 10 HBCD diastereomers. KW - Brominated flame retardants KW - HBCDs KW - Minor isomers KW - X-ray PY - 2011 U6 - https://doi.org/10.1016/j.chemosphere.2011.06.014 SN - 0045-6535 SN - 0366-7111 VL - 84 IS - 7 SP - 900 EP - 907 PB - Elsevier Science CY - Kidlington, Oxford AN - OPUS4-24298 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Nehls, Irene A1 - Hanebeck, Olaf A1 - Becker, Roland A1 - Emmerling, Franziska T1 - N-(beta-carboxyethyl)-alpha-isoleucine N2 - The title compound, {2-[(2-carbamoylethyl)amino]-3-methylpentanoic acid}, C9H18N2O3, is of interest with respect to its biological activity. It was formed during an addition reaction between acrylamide and the amino acid isoleucine. The crystal structure is a three-dimensional network built up by intermolecular N–H···O and O–H···N hydrogen bonds. KW - Acrylamid KW - Isoleucin KW - Derivatisierung PY - 2013 U6 - https://doi.org/10.1107/S160053681205146X SN - 1600-5368 VL - 69 IS - Part 2 SP - o172-o173, sup-1 - sup-7 PB - Munksgaard CY - Copenhagen AN - OPUS4-27573 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mönch, Bettina A1 - Gebert, Antje A1 - Emmerling, Franziska A1 - Becker, Roland A1 - Nehls, Irene T1 - Koenigs-Knorr reaction of fusel alcohols with methyl (1-bromo-2,3,4-tri-O-acetyl-alpha-D-glucopyranosid)uronate leading to the protected alkyl glucuronides-crystal structures and high resolution 1H and 13C NMR data N2 - Crystal structures and high resolution 1H and 13C NMR spectral data for methyl (alkyl 2,3,4-tri-O-acetyl-β-D-glucopyranosid)uronates (alkyl = methyl, ethyl, n-propyl, i-propyl, n-butyl, sec-butyl, i-butyl, n-pentyl, 2-methyl-1-butyl and 3-methyl-1-butyl) are presented. KW - D-Glucuronic acid derivates KW - X-ray analysis KW - High resolution NMR KW - Anomeric configuration KW - Synthesis PY - 2012 U6 - https://doi.org/10.1016/j.carres.2012.01.002 SN - 0008-6215 SN - 1873-426X VL - 352 SP - 186 EP - 190 PB - Elsevier CY - Amsterdam AN - OPUS4-25759 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mönch, Bettina A1 - Emmerling, Franziska A1 - Kraus, Werner A1 - Becker, Roland A1 - Nehls, Irene T1 - Isopropyl 2,3,4,6-tetra-O-acetyl-beta-D-glucopyranoside N2 - The title compound, C17H26O10, was formed by a Koenigs-Knorr reaction of 2,3,4,6-tetra-O-acetyl-α-D-glucopyranosyl bromide and propan-2-ol. The central ring adopts a chair conformation. The crystal does not contain any significant intermolecular interactions. PY - 2013 U6 - https://doi.org/10.1107/S1600536812051483 SN - 1600-5368 VL - 69 IS - Part 2 SP - o157, sup-1 - sup-7 PB - Munksgaard CY - Copenhagen AN - OPUS4-27572 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mönch, Bettina A1 - Emmerling, Franziska A1 - Kraus, Werner A1 - Becker, Roland A1 - Nehls, Irene T1 - n-Propyl 2,3,4,6-tetra-O-acetyl-beta-D-glucopyranoside N2 - The title compound [systematic name: (2R,3R,4S,5R,6R) 2-(acetoxymethyl)-6-propoxytetrahydro-2H-pyran-3,4,5-triyl triacetate], C17H26O10, was formed by a Koenigs-Knorr reaction of 2,3,4,6-tetra-O-acetyl-α-D-glucopyranosyl bromide and n-propanol. The central ring adopts a chair conformation. The crystal does not contain any significant interactions such as hydrogen bonds. PY - 2013 U6 - https://doi.org/10.1107/S1600536812051495 SN - 1600-5368 VL - 69 IS - Part 2 SP - o158, sup-1 - sup-7 PB - Munksgaard CY - Copenhagen AN - OPUS4-27439 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Köppen, Robert A1 - Emmerling, Franziska A1 - Kohl, Anka A1 - Becker, Roland T1 - Delta-Hexabromocyclododecane N2 - (1R,2S,5R,6S,9S,10R)-Hexabromocyclododecane (C12H18Br6, d-HBCD) was crystallized from acetonitrile. The C—Br distances range from 1.962 (8) to 1.982 (8) Å and intermolecular Br...Br contacts contribute to the formation of layers. PY - 2007 U6 - https://doi.org/10.1107/S1600536807026396 SN - 1600-5368 VL - 63 IS - 7 SP - o3105 PB - Munksgaard CY - Copenhagen AN - OPUS4-15048 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Köppen, Robert A1 - Emmerling, Franziska A1 - Becker, Roland T1 - Decabromodiphenylethane N2 - Decabromo­diphenyl­ethane [systematic name: 1,1'-ethane-1,2-diylbis(penta­bromo­benzene)], C14H4Br10 (DBDPE), was crystallized from toluene. The mol­ecule shows crystallographic inversion symmetry. The C—Br distances are in the range 1.873 (7)–1.891 (6) Å; inter­molecular BrBr contacts contribute to the formation of ribbons. KW - Single-crystal X-ray study KW - T = 273 K KW - R factor = 0.043 KW - wR factor = 0.121 KW - Data-to-parameter ratio = 20.4 PY - 2007 U6 - https://doi.org/10.1107/S1600536807000219 SN - 1600-5368 VL - 63 IS - 2 SP - o585 EP - o586 PB - Munksgaard CY - Copenhagen AN - OPUS4-14565 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Köppen, Robert A1 - Becker, Roland A1 - Emmerling, Franziska A1 - Jung, Christian A1 - Nehls, Irene T1 - Enantioselective Preparative HPLC Separation of the HBCD-Stereoisomers from the Technical Product and Their Absolute Structure Elucidation Using X-Ray Crystallography N2 - 1,2,5,6,9,10-Hexabromocyclododecane (HBCD) is a widely used flame retardant, which tends to persist in the environment and accumulates in biota. The six stereoisomers (three racemates named α-, β-, and γ-HBCD) of the technical mixture were isolated with high-performance liquid chromatography (HPLC). Direct separations were performed on a chiral stationary phase containing permethylated -cyclodextrin (NUCLEODEX -PM column) and the pure enantiomers of α-, β-, and γ-HBCD were physically characterized for the first time. The absolute configurations of all six isomers were determined by anomalous dispersion using single crystal X-ray crystallography. Optical rotations αD in tetrahydrofuran were +4.2/-4.0 (α-HBCD), +26.1/-27.5 (β-HBCD), and +68.0/-66.3 (γ-HBCD). The sense of rotation could be correlated with the absolute configurations of α-, β-, and γ-HBCD enantiomers and their order of elution on a chiral permethylated β-cyclodextrin-bonded stationary phase. The diastereomers α-, β-, and γ-HBCD displayed distinctly different melting points as well as 1H-, 13C NMR, and IR spectra. KW - Brominated flame retardant KW - Chiral separation KW - Anomalous dispersion KW - Crystal structures KW - Optical rotation KW - Absolute configuration PY - 2007 U6 - https://doi.org/10.1002/chir.20366 SN - 0899-0042 SN - 1520-636X VL - 19 IS - 3 SP - 214 EP - 222 PB - Wiley-Liss CY - New York, NY AN - OPUS4-14718 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Köppen, Robert A1 - Becker, Roland A1 - Emmerling, Franziska A1 - Jung, Christian A1 - Nehls, Irene T1 - HBCD enantiomers: absolute configurations and thermal rearrangement T2 - Organohalogen Compounds PY - 2006 UR - http://www.dioxin20xx.org/pdfs/2006/06-466.pdf VL - 68 SP - 1991 EP - 1994 PB - Norwegian Institute of Public Health AN - OPUS4-14540 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Emmerling, Franziska A1 - Becker, Roland A1 - Reck, Günter T1 - Mixed crystal of bis(µ2-N,N-di-n-butyldithiocarbamato-S,S,S')-bis(N,N-di-n-butyldithiocarbamato-S,S')-di-zinc(II) and bis(µ2-N,N-di-n-butyldithiopercarbamato-S,O,O')-bis(N,N-di-n-butyldithiocarbamato-S,S')-di-zinc(II) N2 - The title compounds Zn2[S2CN(n-C4H9)2]4 1 and Zn2[(S(SO)CN(n-C4H9)2)(S2CN(n-C4H9)2)]2 3 build mixed crystals in the ratio 0.42: 0.58. Each compound forms dimers, in which the monomer moieties are related via a two-fold axis, coinciding with that of the monoclinic space group C2/c. The lattice parameters are a = 23.581(9), b = 17.112(5), c = 16.372(9) Å, and β = 128.33(3)°. KW - Crystal structure KW - Zinc KW - Dithiocarbamate KW - Dithiopercarbamate PY - 2007 U6 - https://doi.org/10.1002/crat.200710956 SN - 0023-4753 SN - 1521-4079 SN - 0232-1300 VL - 42 IS - 10 SP - 1018 EP - 1023 PB - Wiley-VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-17843 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -