scholarly journals Organic and inorganic templates bearing CCo3(CO)9 cluster fragments: X-ray crystal structures of C(CH2OCOCCl3)4 and of CH3C(O)CHC(OH)MLn where MLn = CCo3(CO)9 or (C6H5)Cr(CO)3

1995 ◽  
Vol 73 (7) ◽  
pp. 1196-1205 ◽  
Author(s):  
Lisa C.F. Chao ◽  
Andreas Decken ◽  
James F. Britten ◽  
Michael J. McGlinchey

Pentaerythritol and trichloroacetyl chloride react to yield the tetrakis-trichloroacetate ester C(CH2-O2C-CCl3)4, 5, which crystallizes in the triclinic space group [Formula: see text] with a = 9.874(2) Å, b = 11.811(2) Å, c = 12.858(3) Å, α = 114.35(3)°, β = 95.63(3)°, γ = 99.11 (3)°, and V = 1326.5(5) Å3 for Z = 2. The molecule adopts a geometry in which the trichloroacetate chains fold to produce a flattened tetrahedron, giving a molecule of approximate D2d symmetry. Treatment of 5 with CO2(CO)8 gave, as the highest molecular weight product, the tris-cluster complex C[CH2-O2C-CCo3(CO)9]3(CH2-O2C-CCl3), 6, rather than the tetra-cluster C[CH2-O2C-CCo3(CO)9]4, 7. A space-filling model of 7, derived by replacing the CCl3 groups in 5 by CCo3(CO)9 moieties, exhibited considerable molecular crowding. Reaction of several 1,1,1-trichloroacetylacetonate salts with Co2(CO)8 gave the corresponding cluster complexes of Co(II), Co(III), or Al(III). The uncomplexed cluster ligand CH3C(O)CHC(OH)CCo3(CO)9, 9, crystallizes in the orthorhombic space group Pna21 with a = 16.226(2) Å, b = 11.6300(10) Å, c = 9.919(2) Å, V = 1871.7(4) Å3 for Z = 4. The direction of enolization of 9 has been studied by EHMO calculations. The tendency to enolize is also found in (benzoylacetone)Cr(CO)3, 17, which crystallizes in the tetragonal space group P43212 with a = 10.0840(10) Å, b = 10.0840(10) Å, c = 25.387(5) Å, V = 2581.5(6) Å3 for Z = 8. Keywords: inorganometallic clusters.

1998 ◽  
Vol 53 (2) ◽  
pp. 206-210 ◽  
Author(s):  
D. Sonnak ◽  
W. Preetz

Abstract X-ray structure determinations have been performed on single crystals of trans-(Ph4P)2-[B6H4I2] (1) (triclinic, space group P1̄, a = 9.9680(12), b = 10.9690(11), c = 11.0470(14) Å,α = 88.167(9), β = 80.466(12), γ = 68.839(11)°, Z = 1), mer-(Ph4P)2[B6H3I3] · 2 CH2Cl2 (2)(triclinic, space group P1̄, a = 11.8694(11), b = 15.1699(13), c = 17.051(2) Å, α = 75.118(9), β = 71.953(10), γ = 69.331(8)°, Z = 2), trans-(Ph4P )2[B6H2I4] · 2 CH3CN (3) (monoclinic, space group P21/n, a = 14.9665(10), b = 7.6783(10), c = 23.385(3) Å, β = 95.78(9)°, Z = 2), and (CH2Py2)[B6HI5] (4) (orthorhombic, space group Pnma, a = 13.660(2), b = 11.8711(13), c = 13.839(2) Å, Z = 4). The B6 octahedra are compressed in the direction of the B-I bonds, resulting in shortened diagonal B ··· B distances with average values of the groups I-B ··· B-I = 2.37 and I-B ··· B-H = 2.43 Å as compared with H-B ··· B-H = 2.49 Å.


1999 ◽  
Vol 55 (1) ◽  
pp. 85-94 ◽  
Author(s):  
James A. Kaduk ◽  
Joseph T. Golab

The crystal structures of 2,6-naphthalenedicarboxylic acid (NDA) and dimethyl 2,6-naphthalenedicarboxylate (NDC) have been solved ab initio using a combination of X-ray powder diffraction and computational chemistry techniques. These two crystal structures, and that of 2,6-dimethylnaphthalene (DMN), have been refined by the Rietveld technique. DMN crystallizes in the orthorhombic space group Pbca, with a = 7.4544 (4), b = 6.0826 (6), c = 20.0946 (12) Å, V = 911.1 (1) Å3 and Z = 4. The structure consists of a herringbone stacking parallel to a, resulting in loosely bound layers perpendicular to c. NDA crystallizes in the triclinic space group P1¯, with a = 3.7061 (8), b = 7.4688 (14), c = 8.5352 (22) Å, α = 86.62 (2), β = 85.49 (2), γ = 87.99 (2)°, V = 235.00 (6) Å3 and Z = 1. The structure consists of loosely packed hydrogen-bonded chains along [11¯1]. NDC crystallizes in the monoclinic space group P21/c, with a = 13.41931 (14), b = 6.14869 (5), c = 7.15257 (5) Å, β = 100.400 (1)°, V = 580.47 (1) Å3 at 300 K and Z = 2. The structure consists of layers of NDC molecules perpendicular to a. The ester group is twisted 20° out of the mean ring plane in NDC. The conformations of the carboxyl groups in NDA and NDC differ. MP2 calculations suggest that the observed twist in NDC corresponds to an increase in conformational energy of 9 kJ mol−1.


1999 ◽  
Vol 54 (6) ◽  
pp. 767-771 ◽  
Author(s):  
L. Homolya ◽  
S. Strueß ◽  
W. Preetz

The crystal structures of trans-(n-Bu4N)2[ReCl4I(NCS)] (triclinic, space group P1, a = 11.268(3), b = 11.696(2), c = 18.109(3) A, a = 98.68(2) β = 106.40(2), γ= 97.58(2)°, Z = 2)and trans-(n-Bu4N)2 [ReCl4I(NCSe)] (orthorhombic, space group P212121 a = 11.839(2), b = 12.2679( 10), c = 31.136(5) A, Z = 4) have been determined by single crystal X-ray diffraction analysis. Based on the molecular parameters of the X-ray determinations the low temperature (10 K) IR and Raman spectra o f the (n-Bu4N) salts have been assigned by normal coordinate analysis. The valence force constants are fd(ReN) = 1.69(NCS) and 1.65(NCSe) mdyn/Å


1986 ◽  
Vol 41 (10) ◽  
pp. 1223-1229 ◽  
Author(s):  
H.-D. Hausen ◽  
W. Schwarz ◽  
G . Rajca ◽  
J. Weidlein

Abstract Spectra and Crystal Structures of the Adducts C l5Sb • [N(/-C3H 7)C N (i-C3H 7)] and C l4Sn • 2 [N(/-C3H 7)CN(/-C3H 7)j X-Ray, Vibrational Data, Diisopropylcarbodiimide Adducts of SbCl5, SnCl4 Thecarbodiimide adducts Cl5Sb <-(—N (R) = C = N R)(1) and Cl4S n ^ (-N (R) = C = N R) 2(2)(R = /-C3H 7) have been prepared by the reaction o f R —N = C —N — R with SbCl5 in a 1:1 and with SnCl4 in a 2:1 molar ratio, respectively. The vibrational spectra (IR and Raman) of both compounds have been regarded and assigned to the skeleton modes. The X-ray structure determination shows the orthorhombic space group Pna2, with 4 formula units per unit cell for 1. Adduct 2 has a trans-configuration and crystallizes in the triclinic space group P 1 with only one molecule per unit cell.


1998 ◽  
Vol 53 (11) ◽  
pp. 1329-1334 ◽  
Author(s):  
L. Homolya ◽  
S. Strueß ◽  
W. Preetz

The crystal structures of cis-(n-Bu4N)2[ReCl4(NCS)2] (triclinic, space group P1̅, a = 11,245( 1), b = 20.174(3), c = 21.320(8) Å, a =109.06(2), β = 96.46(2), γ = 98.22(5)°, Z = 4) and cis-(Ph4P)2[ReCl4(NCSe)2]·2CH2Cl2 (triclinic, space group P1̅, a = 10.341(2), b = 13.436(3), c = 19.616(4) Å, α = 92.70(2), β = 92.02(2), γ = 89.99( 1)°, Z= 2) have been determined by single crystal X-ray diffraction analysis. Both ambidentate ligands NCS and NCSe are bonded via the N atom. Using the molecular parameters of the X-ray determinations the low temperature (10 K) IR and Raman spectra of the (n-Bu4N) salts have been assigned by normal coordinate analysis based on a modified valence force field. The valence force constants fd(ReN) are 1,78(NCS) and 1,79(NCSe) mdyn/ Å.


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−.


2007 ◽  
Vol 62 (10) ◽  
pp. 1271-1276 ◽  
Author(s):  
Liang Chen ◽  
Xian-Wen Wanga ◽  
Jing-Zhong Chen ◽  
Jian-Hong Liu

The complexes Mn(Cl3CCOO)2(4,4′-bpy) (1) and [Cu2(ClCH2COO)(2,2′-bpy)2(OH)(H2O)]-(NO3)2(2) (bpy = bipyridine) were generated under mild reaction conditions and characterized by IR spectra, thermogravimetric analysis (TGA), X-ray powder diffraction (XRD), and single crystal X-ray diffraction. Compound 1 exhibits a two-dimensional network with octahedrally coordinated Mn(II) atoms linked by 4,4′-bpy ligands and Cl3COO− ligands. Compound 2 features a supramolecular structure of binuclear complexes, with edge-sharing five-coordinated square-pyramidal units bridged by the ClCH2COO− ligand, an OH− group and a water molecule. Complex 1 crystallizes in the orthorhombic space group Pbcn with cell parameters: a = 16.5390(17), b = 11.6396(17), c = 9.9181(12) Å, V = 1909.3(4) Å3, Z = 4, wR2 = 0.1576. Complex 2 crystallizes in the triclinic space group P1̅ with cell parameters: a = 7.6190(15), b = 11.151(2), c = 16.640(3) Å , α = 73.13(3), β = 80.89(3), γ = 74.51(3)°, V = 1298.73(4) Å3, Z = 2, wR2 = 0.1265.


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.


2011 ◽  
Vol 66 (4) ◽  
pp. 359-365 ◽  
Author(s):  
Olaf Reckeweg ◽  
Armin Schulz ◽  
Francis J. DiSalvo

Single crystals of Eu5(BO3)3Cl were obtained by serendipity by reacting Eu2O3 and Mg with B2O3 at 1300 K in the presence of an NaCl melt for 13 h in silica-jacketed Nb ampoules. Ba5(BO3)3X (X = Cl, Br) crystals were formed by direct synthesis from appropriate amounts of Ba(OH)2, H3BO3 and the respective barium halide (hydrate) in alumina crucibles kept in the open atmosphere at 1300 K for 13 h. The crystal structures of the title compounds were determined with single-crystal X-ray diffraction. All compounds crystallize isotypically to Sr5(BO3)3Cl in the orthorhombic space group C2221 (no. 20, Z = 4) with the lattice parameters a = 1000.34(7), b = 1419.00(9), c = 739.48(5) pm for Eu5(BO3)3Cl, a = 1045.49(5), b = 1487.89(8), c = 787.01(4) pm for Ba5(BO3)3Cl, and a = 1048.76(7), b = 1481.13(9) and c = 801.22(5) pm for Ba5(BO3)3Br. The Raman spectra of all compounds were acquired and are presented and compared to literature data. The incremental volume of the orthoborate (BO3)3− anion has been determined and is compared to the Biltz volume


1999 ◽  
Vol 64 (1) ◽  
pp. 89-98 ◽  
Author(s):  
Bohumil Kratochvíl ◽  
Alexandr Jegorov ◽  
Svetlana Pakhomova ◽  
Michal Hušák ◽  
Petr Bulej ◽  
...  

The structures of O-acetyl-(4R)-4-(E-2-butyl)-4,N-dimethyl-L-threonyl-cyclosporin A (1) and O-acetyl-(4R)-4-[E-2-(4-bromobutyl)]-4,N-dimethyl-L-threonyl-cyclosporin A (2) were determined by X-ray diffraction methods and compared with the structure of related cyclosporins. In contrast to expectation, neither the acetylation nor the subsequent bromination of 1 affects the conformation and packing of cyclosporins in the solid state. Both compounds are isomorphous and crystallize in the orthorhombic space group P212121 with a = 12.936(2) Å, b = 15.590(2) Å, c = 36.280(3) Å, and a = 12.916(3) Å, b = 15.675(4) Å, c = 36.715(7) Å, for 1 and 2, respectively.


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