Divalent Metal-Complexes of 2-Fluorophenoxyacetic Acid - the Crystal-Structures of 2-Fluorophenoxyacetic Acid, Tetraaquabis(2-Fluorophenoxyacetato)Zinc(II) Dihydrate and Aquabis(2-Fluorophenoxyacetato)Bis(Pyridine)Copper(II)

1986 ◽  
Vol 39 (11) ◽  
pp. 1823 ◽  
Author(s):  
CHL Kennard ◽  
EJ Oreilly ◽  
S Schiller ◽  
G Smith ◽  
AH White

The crystal structures of 2-fluorophenoxyacetic acid ( oflpaH ) and the metal complexes aquabis (2-fluorophenoxyacetato) bis (pyridine)copper(II) (1) and tetraaquabis (2-fluorophenoxyacetato)zinc(II) dihydrate (2) have been determined by X-ray diffraction and refined to residuals R 0.036, 0.041, 0.025 for 641, 863 and 1505 observed reflections respectively. The acid crystallizes in a monoclinic cell, space group P21/c with a 6.207(2), b 19.363(8), c 6.999(2) Ǻ, β 114.81(2)� and Z 4. The molecules form planar, centrosymmetric , hydrogen-bonded cyclic dimers [O...O, 2.618(4)Ǻ]. Complex (1) is orthorhombic, space group P2cb with two molecules in a cell of dimensions a 5.621 (2), b 17.218(7), c 13.288(6)Ǻ while (2) is monoclinic, space group P21/c, a 6.597(2), b 5.279(2), c 30.079(10) Ǻ, β 94.65(3)�; with Z 2. Complex (1) has square-pyramidal geometry with the basal plane containing two trans related carboxyl oxygens [Cu-O, 1.944(4)Ǻ] and two trans related pyridine nitrogens [Cu-N, 2.030(5)Ǻ]. A water molecule occupies the apex of the square pyramid [Cu-OW, 2.199(8)Ǻ]. Complex (2) has octahedral geometry with the MO6 octahedron containing two trans related carboxyl oxygens [Zn-O, 2.122(2)Ǻ] and four water oxygens [Zn-OW, 2.069(2), 2.085(2)Ǻ]. Preliminary X-ray data also confirm that the magnesium(II) and manganese(II) complexes of 2-fluorophenoxyacetic acid are isomorphous with (2) but different from the cobalt(II) derivative.

1997 ◽  
Vol 50 (9) ◽  
pp. 903 ◽  
Author(s):  
Trevor W. Hambley ◽  
Walter C. Taylor ◽  
Stephen Toth

Four novel norditerpenoids were isolated from a new encrusting sponge, conveniently labelled Aplysilla pallida. The structures of aplypallidenone (1), aplypallidoxone (2), aplypallidione (3) and aplypallidioxone (4) were elucidated by spectroscopic studies and the crystal structures of aplypallidenone and aplypallidoxone have been determined by X-ray diffraction methods. The structure of (1) was refined to a residual of 0·040 for 1665 independent observed reflections and the structure of (2) was refined to a residual of 0·031 for 1699 independent observed reflections. The crystals of (1) are orthorhombic, space group P212121, a 7·728(2), b 10·838(4), c 24·880(5) Å, Z 4. Those of (2) are monoclinic, space group C 2, a 23·927(7), b 6·674(2), c 14·033(3) Å, Z 4.


1995 ◽  
Vol 73 (9) ◽  
pp. 1520-1525
Author(s):  
Luciano Antolini ◽  
Ugo Folli ◽  
Dario Iarossi ◽  
Adele Mucci ◽  
Silvia Sbardellati ◽  
...  

The crystal structures of the title compounds were determined by single crystal X-ray diffraction techniques. The molecule of the Z isomer, which crystallizes in the monoclinic space group C2/c with Z = 4 in a cell of dimensions a = 14.891 (2), b = 10.780(2), c = 8.769(1) Å, β = 97.47(2)°, V = 1395.7(7) Å3 has crystallographic twofold symmetry. The E form crystallizes in the orthorhombic space group Pbca with a = 11.730(1), b = 6.932(1), c = 16.841(1) Å, V = 1369.4(2) Å3 and Z = 4. Its molecules have crystallographically dictated [Formula: see text] symmetry. In both isomers the phenyl rings are roughly perpendicular to the average ethylene plane. The atoms characterizing this plane show significant deviations from planarity in the Z isomer. Marked bond-angle distortions at the ethene carbons of both structures are observed. The 1H and 13C NMR spectra of the compounds were measured and, particularly in the case of the 1H chemical shifts, fall into two quite separate spectral regions. At low temperature, two conformational isomers, those with different relative orientation of the C—Cl bonds of the phenyl rings, are observed in the spectrum of each compound. Keywords: chlorostilbenes, overcrowded molecules. X-ray structure, conformations, NMR spectroscopy.


1985 ◽  
Vol 38 (9) ◽  
pp. 1381 ◽  
Author(s):  
CHL Kennard ◽  
EJ O'Reilly ◽  
G Smith ◽  
TCW Mak

The crystal structures of 2-formylphenoxyacetic acid ( ofpaH ), tetraaquabis (2-formylphenoxyacetato)-cobalt(II) (1) and tetraaquabis (2- formylphenoxyacetato )zinc(II) (2) have been determined by X-ray diffraction and refined to residuals R 0.039, 0.058 and 0.045 for 1197, 1178 and 1230 observed reflections respectively. 2-Formylphenoxyacetic acid crystallizes in a monoclinic cell, space group P21/n with a 8.066(2), b 7.375(1), c 14.206(2) Ǻ, β 98.12(1)° and Z 4. The planar molecules form unusual hydrogen-bonded chain polymers (O…O 2.694(3)Ǻ] linked through the carboxyl groups. The complexes (1) and (2) are isomorphous, the comparative cells being a 5.036(1), b 13.463(3), c 15.083(4) Ǻ, β 96.88(2)° for (1), and a 5.044(1), b 13.481(3), c 15.055(4) Ǻ, β 96.95(2)° for (2), with Z 2 and space group P21. The complexes have four waters and two trans-related carboxyl oxygens [mean M-O distances 2.129(5) and 2.117(3) Ǻ respectively] completing almost regular octahedral stereochemistries . The nickel(II) complex [Ni( ofpa )(H2O)4] is probably not isostructural with (1) and (2), and the copper(II) complex is also different, with formula [Cu( ofpa )2(H2O)2].


1982 ◽  
Vol 35 (2) ◽  
pp. 457 ◽  
Author(s):  
RM Carman ◽  
SS Smith ◽  
CHL Kennard ◽  
G Smith ◽  
AH White ◽  
...  

The crystal structures of two γ-lactones of the bicyclo[2,2,2]octane series, endo-3-carboxy-exo-5- iodobicyclo[2,2,2]octane-2,6-carbolactone (2; R = CO2H) and exo-3-methoxycarbonyl-endo-5-acetoxybicyclo[2,2,2] octane-2,6-carbolactone (7b), have been determined by direct methods from three-dimensional X-ray data and refined by least-squares to final residuals of 0.033 (2; R = CO2H) and 0.036 (7b) for 1918 and 630 'observed' reflections respectively. Crystals for (2; R = CO2H) are monoclinic, space group P21/c with Z 8 in a cell of dimensions a 7.192(2), b 23.785(8), c 13.199(5) �, β 105.35(2)�, while (7b) crystallizes in the orthorhombic space group P212121 with Z 4 in a cell of dimensions a 13.347(7), b 11.839(7), c 8.227(11) �.


2020 ◽  
Vol 75 (5) ◽  
pp. 509-516 ◽  
Author(s):  
Timotheus Hohl ◽  
Torben Sinn ◽  
Constantin Hoch

AbstractFour solvent complexes of beryllium iodide were prepared by dissolving BeI2 in N,N-dimethyl formamide (DMF), pyridine (Pyr), N-methyl pyrrolidone (NMP) and 2,6-dimethyl pyridine (2,6-lutidine, Lut). Their crystal structures were established from single crystal X-ray diffraction. For [Be(DMF)4]I2 a new modification is reported (monoclinic, space group P21/c, a = 12.491(2), b = 11.593(2), c = 15.310(3) Å, β = 94.7073(6)°). In [Be(Pyr)4]I2 (monoclinic, space group C2/c, a = 17.8799(13), b = 7.6174(5), c = 18.2611(14) Å, β = 113.508(4)°) and [Be(NMP)4]I2 (orthorhombic, space group Pbca, a = 13.941(5), b = 15.754(3), c = 24.634(7) Å) homoleptic tetrahedral complex cations are formed, while the sterically demanding solvent ligand Lut yields a neutral complex with covalently bound iodine ligands [BeI2(Lut)2] (monoclinic, space group P21/c, a = 7.8492(9), b = 24.265(3), c = 27.037(3) Å, β = 97.076(3)°). Their electrochemical stability with respect to their application as beryllium electrolytes for deposition of beryllium from solution is discussed.


1988 ◽  
Vol 41 (5) ◽  
pp. 683 ◽  
Author(s):  
TCW Mak ◽  
WH Yip ◽  
CHL Kennard ◽  
G Smith ◽  
EJ Oreilly

The crystal structures of perfluorophenoxyacetic acid [(2,3,4,5,6- pentafluorophenoxy )acetic acid] and its anhydrous complexes with silver(I) and mercury(I) have been determined by X-ray diffraction and refined to residuals R = 0.046, 0.042 and 0.104 for 1235, 1789 and 2750 observed reflections respectively. The acid forms the usual hydrogen- bonded cyclic dimers [O---O, 2.705(3)Ǻ] with the oxyacetic acid side- chain synclinally oriented. Crystals age triclinic, space group Pī with Z 2 in a cell of dimensions a 7.479(1), b 7.592(2), c 8.463(2)Ǻ,α 80.15(2),β 85.34(2),γ 61.31(1)Ǻ. The silver complex, [Ag2L2],(1), has crystals with a 5.992(3), b 30.22(2), c 5.277(2)Ǻ, β 106.42(5)°, space group P21/a and Z 2. The bis-carboxylato (O,O′) dimers have Ag-Ag 2.943(1)Ǻ with Ag-O, 2.203, 2.230(3)Ǻ and O-Ag-O 161.6(2)°. The complex with mercury(I), [Hg2L2]n, (2), is centrosymmetric with the usual linear O-Hg-Hg-O-bonds [Hg-Hg, 2.514(1)Ǻ; Hg-O, 2.13(1)Ǻ; O-Hg-Hg, 173.9(2)°]. Longer peripheral bonds to Hg [Hg-O, 2.63(1)Ǻ] produce a polymeric structure. Crystals of (2) are triclinic, space group Pī with Z 1 in a cell of dimensions a 5.038(1), b 5.970(1), c 15.774(6)Ǻ, α 80.77(2),β 86.42(2),γ 84.38(2)°.


1992 ◽  
Vol 47 (3) ◽  
pp. 305-309 ◽  
Author(s):  
Anja Edelmann ◽  
Sally Brooker ◽  
Norbert Bertel ◽  
Mathias Noltemeyer ◽  
Herbert W. Roesky ◽  
...  

Abstract The Molecular Structures of [2,4,6-(CF3)3C6H2S]2 (1) [2,4,6-Me3C6H2Te]2 and [2-Me2N-4,6-(CF3)2C6H2Te]2 (3) have been determined by X-ray diffraction. Crystal data: 1: orthorhombic, space group P212121, Z = 4, a = 822.3(2), b = 1029.2(2), c = 2526.6(5) pm (2343 observed independent reflexions, R = 0.042); 2: orthorhombic, space group Iba 2, Z = 8, a = 1546.5(2), b = 1578.4(2), c = 1483.9(1) pm (2051 observed independent reflexions, R = 0.030); 3: monoclinic, space group P 21/c, Z = 4, a = 1118.7(1), b = 1536.5(2), c = 1492.6(2) pm, β = 98.97(1)° (3033 observed independent reflexions, R = 0.025).


1988 ◽  
Vol 41 (3) ◽  
pp. 283 ◽  
Author(s):  
GB Robertson ◽  
PA Tucker

The structures of two crystalline modifications of mer -(Pme2Ph)3H-cis-Cl2IrIII, (1), have been determined from single-crystal X-ray diffraction data. Modification (A) is monoclinic, space group P21/c with a 12.635(1), b 30.605(3), c 14.992(2)Ǻ, β 110.01(2)° and Z = 8. Modification (B) is orthorhombic, space group Pbca with a 27.646(3), b 11.366(1), c 17.252(2)Ǻ and Z = 8. The structures were solved by conventional heavy atom techniques and refined by full-matrix least- squares analyses to conventional R values of 0.037 [(A), 8845 independent reflections] and 0.028 [(B), 5291 independent reflections]. Important bond lengths [Ǻ] are Ir -P(trans to Cl ) 2.249(1) av. (A) and 2.234(1) (B), Ir -P(trans to PMe2Ph) 2.339(2) av. (A) and 2.344(1), 2.352(1) (B), Ir-Cl (trans to H) 2.492(2), 2.518(2) (A) and 2.503(1) (B) and Ir-Cl (trans to PMe2Ph)2.452(2) av. (A) and 2.449(1)(B). Differences in chemically equivalent metal- ligand bond lengths emphasize the importance of non-bonded contacts in determining those lengths.


1996 ◽  
Vol 49 (12) ◽  
pp. 1301 ◽  
Author(s):  
GW Allen ◽  
ECH Ling ◽  
LV Krippner ◽  
TW Hambley

The preparation and purification of [Pt( hpip )Cl2] and [Pd( hpip )Cl2] ( hpip = homopiperazine = 1,4-diazacycloheptane) are described. Crystal structures of [Pt( hpip )Cl2] and [Pd( hpip )Cl2] have been determined by X-ray diffraction methods and refined to R values of 0.023 (932 F) and 0.023 (948 F). The crystals of [Pt( hpip )Cl2] are orthorhombic, space group Pbcm , a 7.7019(8), b 9.8080(12), c 12.1944(14) Ǻ, and those of [Pd( hpip )Cl2] are monoclinic, space group P21/m, a 6.1001(9), b 11.527(2), c 6.458(I) Ǻ, β 106.30(2)°. The seven- membered rings of the ligands in both complexes adopt boat-like conformations in which the five- membered chelate ring has an eclipsed N-C-C-N group and the six- membered chelate ring adopts a chair conformation. Molecular mechanics methods were used to investigate whether this conformation was a crystallographic artefact but it was found to be real. An alternative conformation in which the six-membered chelate ring adopts a skew-boat conformation was also investigated. It was found to be less stable than the conformation observed in the crystal structures, but to a degree that depends on whether non-bonded interactions involving the metal atom were included or not.


2003 ◽  
Vol 58 (7) ◽  
pp. 620-626 ◽  
Author(s):  
Franziska Emmerling ◽  
Caroline Röhr

The new alkaline metal arsenates(III) were synthesized at a temperature of 500 °C via reaction of stoichiometric mixtures of the elemental alkali metals A and As2O3. In the crystal structures of the four title compounds, which have been determined by single crystal x-ray diffraction, the As(III) atoms are in ψ-tetrahedral coordination by oxygen exclusively. In NaAsO2 (orthorhombic, space group Pbcm, a = 1429.6(9), b = 677.3(3), c = 509.1(2) pm, Z = 8) and the compounds AAsO2 (A = K/Rb, orthorhombic, space group Pbcm, a = 715.1(2)/729.7(5), b =748.0(1)/775.2(5), c = 539.20(17)/541.1(3) pm, Z = 4) the AsO3 ψ-tetrahedra are condensed to form zig-zag chains [AsOO2/2]−. In the Cs phase Cs3As5O9 with a lower alkaline metal content (trigonal, space group P31m, a = 845.5(3), c = 602.6(2) pm, Z = 1) the two crystallographically independent ψ-tetrahedra AsO3/2 and AsOO2/2 are connected in a 2:3 ratio to give polar sheets [As5O9]3−.


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