Syntheses and reactivity of square-planar Rh(I) complexes, LRh(CO) (L = unsymmetric tridentate chelating pyrazolylgallate ligand). X-ray crystal structures of [Me2Gapz(OCH2CH2NH2)]Rh(CO) and [Me2Gapz(OCH2CH2NMe2)]Rh(COMe)I (pz = pyrazolyl, N2C3H3)

1985 ◽  
Vol 63 (11) ◽  
pp. 3019-3026 ◽  
Author(s):  
Brenda M. Louie ◽  
Steven J. Rettig ◽  
Alan Storr ◽  
James Trotter
Keyword(s):  
Crystal Structures ◽  
Heavy Atom ◽  
Least Square ◽  
Insertion Reaction ◽  
Space Group ◽  
Physical Measurements ◽  
Square Planar ◽  
Migratory Insertion ◽  
Complex Crystal

The syntheses and characterization of a number of square-planar Rh(I) monocarbonyl complexes incorporating un-symmetrical, tridentate, pyrazolylgallate ligands in a meridional coordination mode are described. Oxidative addition reactions of these complexes are detailed and a facile migratory insertion reaction, following the addition of methyl iodide, has resulted in a five-coordinate square-pyramidal Rh(III) acetyl complex. Crystal structures of two compounds are presented, [Me2Gapz(OCH2CH2NH2)]Rh(CO) and [Me2Gapz(OCH2CH2NMe2)]Rh(COMe)I, and confirm the molecular arrangements predicted on the basis of other physical measurements. Crystals of the former are monoclinic, a = 10.212(2), b = 7.8484(5), c = 16.733(2) Å, β = 105.133(6)°, z = 4, space group P21/c; and those of the latter are monoclinic, a = 10.0960(11), b = 11.5352(8), c = 15.871(2) Å, β = 105.764(6)°, z = 4, space group P21/n. Both structures were solved by conventional heavy atom methods and were refined by full-matrix least-square procedures to R = 0.026 and 0.036, respectively, for 2142 and 2941 reflections with I ≥ 3σ(I).

Synthesis and characterization of LMo(CO)3M(PPh3)x (where L = tridentate pyrazolyl-gallate or -borate ligand; M = Rh, x = 2; M = Cu, x = 1). X-ray crystal structures of [MeGapz3]Mo(CO)3Rh(PPh3)2 and [MeGapz3]Mo(CO)3Cu(PPh3) (where pz = pyrazolyl, N2C3H3)

1986 ◽  
Vol 64 (2) ◽  
pp. 373-386 ◽  
Author(s):  
Gregory A. Banta ◽  
Brenda M. Louie ◽  
Emmanuel Onyiriuka ◽  
Steven J. Rettig ◽  
Alan Storr
Keyword(s):  
Least Squares ◽  
Crystal Structures ◽  
Heavy Atom ◽  
Synthesis And Characterization ◽  
Octahedral Structure ◽  
Full Matrix ◽  
Space Group ◽  
X Ray

The reactions of the LMo(CO)3− ions (L = MeGapz3, HBpz3, Me2Gapz(OCH2CH2NMe2)) with [Cu(PPh3)Cl]4 and Rh(PPh3)3Cl have yielded complexes with Mo—Cu and Mo—Rh bonds. The X-ray crystal structures of two such complexes have been determined. Crystals of [MeGapz3]Mo(CO)3Cu(PPh3) are monoclinic, a = 17.071(2), b = 16.738(1), c = 23.641(3) Å, β = 104.899(6)°, Z = 8, space group P21/n, and those of [MeGapz3]Mo(CO)3Rh(PPh3)2, are triclinic, a = 12.519(3), b = 17.182(4), c = 12.071(2) Å, α = 105.02(1), β = 109.87(1), γ = 97.10(2)°, Z = 2, space group [Formula: see text]. Both structures were solved by conventional heavy atom methods and were refined by full-matrix least-squares procedures to R = 0.040 and Rw = 0.035 for 6296 reflections with I ≥ 2σ(I) and R = 0.036 and Rw = 0.037 for 5642 reflections with I ≥ 3σ(I), respectively. The former complex provides a rare example of a 3:3:1, or capped octahedral structure, with a short (mean) Mo—Cu distance of 2.513(9) Å. The latter compound displays one terminal and two bridging CO ligands and a Mo—Rh distance of 2.6066(5) Å.

Pyrazagaboles, pyrazolyl-bridged heterocycles containing boron and gallium

1990 ◽  
Vol 68 (1) ◽  
pp. 59-63 ◽  
Author(s):  
Steven J. Rettig ◽  
Mark Sandercock ◽  
Alan Storr ◽  
James Trotter
Keyword(s):  
Least Squares ◽  
Crystal Structures ◽  
Structural Characterization ◽  
Heavy Atom ◽  
Full Matrix ◽  
Space Group ◽  
The Mean

The synthesis and structural characterization of representative and novel pyrazagaboles, boron- and gallium-containing compounds with a central six-membered heterocyclic B—(N—N)2—Ga ring feature, are detailed. Crystals of dimethylgallium-bis(μ-pyrazolyl)dimethylboron are orthorhombic, a = 7.6135(5), b = 16.2917(5), c = 22.331(1) Å, Z = 8, space group Pbca, and those of hydroxy(methyl)galliumbis(μ-pyrazolyl)dimethylboron are orthorhombic, a = 7.6197(3), b = 16.2184(7), c = 22.190(1) Å, Z = 8, space group Pbca. Both structures were solved by conventional heavy atom methods and were refined by full-matrix least-squares procedures to R = 0.054 and 0.040 for 1243 and 1272 reflections with I ≥ 1.5 and 3σ(I), respectively. The crystal structures are isomorphous and both feature six-membered B—(N—N)2—Ga rings having highly asymmetric boat conformations, unlike those observed for the majority of the homobinuclear analogs previously reported. The mean Ga—N and B—N distances in the two compounds are 1.977 and 1.61 Å. Keywords: pyrazagaboles, pyrazolyl-bridged heterocycles, crystal structures, synthesis of pyrazagaboles.

Synthesis and characterization of [Me2Ga(3,5-Me2pz)2]Rh(CO)PPh3 and the X-ray structure of its toluene solvate

1985 ◽  
Vol 63 (2) ◽  
pp. 503-508 ◽  
Author(s):  
Brenda M. Louie ◽  
Steven J. Rettig ◽  
Alan Storr ◽  
James Trotter
Keyword(s):  
Physical Properties ◽  
Least Squares ◽  
Heavy Atom ◽  
Synthesis And Characterization ◽  
Boat Conformation ◽  
Full Matrix ◽  
Space Group ◽  
X Ray ◽  
Square Planar

Details of the synthesis and physical properties of [Me2Ga(3,5-Me2pz)2]Rh(CO)PPh3 are given. Crystals of [dimethylbis(3,5-dimethyl-1-pyrazolyl)gallato-N,N′](triphenylphosphine)carbonylrhodium(I) – toluene (1:1) are triclinic, a = 10.690(2), b = 12.928(2), c = 13.998(2) Å, α = 77.44(1), β = 83.50(1), γ = 72.70(1)°, Z = 2, space group [Formula: see text]. The structure was solved by conventional heavy-atom methods and was refined by full-matrix least-squares procedures to R = 0.039 and Rw = 0.048 for 5987 reflections with I ≥ 3σ(I). The Rh(I) is in a distorted square planar environment with Rh—N = 2.090(3) and 2.097(2), Rh—CO = 1.815(4), and Rh—P = 2.2700(8) Å. The central six-membered RhGaN4 ring has a steep boat conformation with a [Formula: see text] separation of 3.3819(4) Å.

Distorted chiolite crystal structures of α-Na5M3F14 (M=Cr,Fe,Ga) studied by X-ray powder diffraction

2003 ◽  
Vol 18 (2) ◽  
pp. 128-134 ◽  
Author(s):  
A. Le Bail ◽  
A.-M. Mercier
Keyword(s):  
Crystal Structures ◽  
Powder Diffraction ◽  
Room Temperature ◽  
Rietveld Refinements ◽  
Space Group ◽  
X Ray ◽  
Precise Characterization

The crystal structures of the chiolite-related room temperature phases α-Na5M3F14 (MIII=Cr,Fe,Ga) are determined. For all of them, the space group is P21/n, Z=2; a=10.5096(3) Å, b=7.2253(2) Å, c=7.2713(2) Å, β=90.6753(7)° (M=Cr); a=10.4342(7) Å, b=7.3418(6) Å, c=7.4023(6) Å, β=90.799(5)° (M=Fe), and a=10.4052(1) Å, b=7.2251(1) Å, c=7.2689(1), β=90.6640(4)° (M=Ga). Rietveld refinements produce final RF factors 0.036, 0.033, and 0.035, and RWP factors, 0.125, 0.116, and 0.096, for MIII=Cr, Fe, and Ga, respectively. The MF6 polyhedra in the defective isolated perovskite-like layers deviate very few from perfect octahedra. Subtle octahedra tiltings lead to the symmetry decrease from the P4/mnc space group adopted by the Na5Al3F14 chiolite aristotype to the P21/n space group adopted by the title series. Facile twinning precluded till now the precise characterization of these compounds.

Tetrahalogenotellurate(II): Synthese und Kristallstrukturen von Verbindungen mit den Ionen TeX42- (X = Cl, Br, I)/Tetrahalotellurates(II): Syntheses and Crystal Structures of Compounds with TeX42- Ions (X = Cl, Br, I)

1985 ◽  
Vol 40 (2) ◽  
pp. 251-257 ◽  
Author(s):  
Siegfried Pohl ◽  
Wolfgang Saak ◽  
Bernt Krebs
Keyword(s):  
Single Crystal ◽  
Crystal Structures ◽  
Acetonitrile Solution ◽  
Monoclinic Space Group ◽  
Space Group ◽  
X Ray ◽  
Bond Lengths ◽  
Square Planar

Abstract The compounds [(C6H5)4As]2 TeCl4 (1), [(C2H5)4 N]2 TeBr4 · CH3CN (2), and [(C2H5)4N]2TeI4 (3) were prepared by the reaction of Te, X2 , and excess (C2H5)4NX (X = Br, I) in acetonitrile solution or by heating of [(C6H5)4 As]2TeCl6 , Te, and (C6H5)4 ASCl for several hours in the same solvent.The structures of 1-3 were determined from single crystal X-ray data.1 crystallizes in the monoclinic space group P21/n with a = 1061.8(2), b = 1614.2(3), c = 1341.7(3) pm, β = 94.21° and Z = 2; 2: tetragonal, P4/mmm, a = 1039.7(2), c = 690.5(1), Z = 1; 3: tetragonal, I4/mmm, a = 1061.7(2), c = 1342.8(4), Z = 2. In 1-3 Te(II) exhibits a square planar coordination. The Te -CI, Te -Br, and Te-I bond lengths were found to be 260.7 (mean), 275.3, and 298.5 pm, respectively.

scholarly journals The crystal structures of kidwellite and ‘laubmannite’, two complex fibrous iron phosphates

2004 ◽  
Vol 68 (1) ◽  
pp. 147-165 ◽  
Author(s):  
U. Kolitsch
Keyword(s):  
Crystal Structures ◽  
Metal Cation ◽  
Iron Phosphate ◽  
Group Symmetry ◽  
X Ray Diffraction ◽  
Narrow Channels ◽  
Iron Phosphates ◽  
Space Group ◽  
X Ray ◽  
Complex Crystal

AbstractThe previously unknown, complex crystal structures of two fibrous ferric iron phosphate minerals have been solved using single-crystal X-ray diffraction data. The structure of a slightly arsenatian kidwellite has been refined in space group P2/c (a = 20.117(4), b = 5.185(1), c = 13.978(3)Å, β = 107.07(3)°, V = 1393.8(5)Å3, Z = 2) to R1 = 5.21%; a revision of both space group symmetry and chemical formula is proposed. The idealized formula is Na(Fe3+,M)9+x(OH)11(H2O)3(PO4)6, where M = Fe3+, Cu2+ or other metal cation, and x ≈ 0.3. The structure of a slightly arsenatian ‘laubmannite’ (as defined by Moore, 1970) has been refined in space group Pbcm (a = 5.172(1), b = 13.999(3), c = 31.083(6)Å, V = 2250.5(8)Å3, Z = 4) to R1 = 3.14%. The revised, idealized formula is (Fe3+,Fe2+,M)8+x(OH,H2O)9(-H2O)2(PO4)5, where M = Fe3+, Cu2+ or other metal cation, and x ≈ 0.1. The framework structures of both minerals are similar. Dominant building units are dimers composed of face- and edge-sharing FeO6 octahedra. Whereas kidwellite contains an additional trimer built of three corner-sharing FeO6 octahedra, ‘laubmannite’ instead contains a dimer built of two corner-sharing FeO6 octahedra. Kidwellite contains only trivalent iron, while one of the Fe sites in ‘laubmannite’ is occupied by a mixture of Fe3+ and Fe2+ in a 1:1 ratio. In both structures, the FeO6-based building units are linked via corners to PO4 tetrahedra; the M sites are located in narrow channels and have very low occupancies (~2 to 7%) and strongly distorted [6]- or [5+1]-coordinations. Close structural relations between kidwellite and ‘laubmannite’, and other fibrous iron phosphates explain observations of epitaxial intergrowths of them.

Mono- and difunctional furan-based 1,2,3,5-dithiadiazolyl radicals; preparation and solid state structures of 2,5-[(S2N2C)OC4H2(CN2S2)] and 2,5-[(S2N2C)OC4H2(CN)]

1992 ◽  
Vol 70 (3) ◽  
pp. 919-925 ◽  
Author(s):  
A. Wallace Cordes ◽  
Charles M. Chamchoumis ◽  
Robin G. Hicks ◽  
Richard T. Oakley ◽  
Kelly M. Young ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Solid State ◽  
Crystal Structures ◽  
Monoclinic Space Group ◽  
Orthorhombic Space Group ◽  
Space Group ◽  
The Mean ◽  
Solid State Structures ◽  
Solid State Characterization

The preparation and solid state characterization of the bifunctional radical furan-2,5-bis(1,2,3,5-dithiadiazolyl) 2,5-[(S2N2C)OC4H2(CN2S2)] and the related monofunctional radical 2-cyanofuran-5-(1,2,3,5-dithiadiazolyl) 2,5-[(S2N2C)OC4H2(CN)] are described. The crystal structure of 2,5-[(S2N2C)OC4H2(CN2S2)] is orthorhombic, space group Pna21, and consists of interleaved arrays of dimers, for which the mean interannular [Formula: see text] contact is 3.137 Å. The crystal structure of the monofunctional radical 2,5-[(S2N2C)OC4H2(CN)] is monoclinic, space group P21/n, and consists of a ribbon-like network of dimers (mean interannular [Formula: see text] interconnected by close head-to-tail [Formula: see text] contacts. The dimer units form stacks parallel to z, with a mean interdimer [Formula: see text] separation of 3.956 Å. The similarities and differences between these two crystal structures and those of related benzene-substituted systems are discussed. Keywords: dithiadiazolyl radicals, furan-based diradicals, cyanofuran-based radicals, radical dimers, crystal structures.

Rhodium(I) complexes containing bidentate pyrazolylgallate ligands. X-ray crystal structures of [Me2Gapz2]Rh(COD), [Rh(μ-3,5-Me2pz)(CO)2]2, and [Rh(μ-3,5-Me2pz)(COD)]2

1984 ◽  
Vol 62 (6) ◽  
pp. 1057-1067 ◽  
Author(s):  
Brenda M. Louie ◽  
Steven J. Rettig ◽  
Alan Storr ◽  
James Trotter
Keyword(s):  
Solid State ◽  
Structural Parameters ◽  
Heavy Atom ◽  
Boat Conformation ◽  
Nmr Studies ◽  
Space Group ◽  
H Nmr ◽  
Square Planar ◽  
Dirhodium Complexes

The synthesis and characterization of the complexes [Me2Gapz2]Rh(LL) (where LL = COD, (CO)2, (PPh3)2, or (PPh3)(CO)), incorporating the bidentate, chelating, dimethylbis(1-pyrazolyl)gallate ligand are described. Non-rigidity in solution has been demonstrated by 1H nmr studies for some of the complexes. A crystal structure determination of the COD complex has confirmed the boat conformation for the Ga—(N—N)2—Rh six-membered ring in this complex in the solid state. In addition, the solid state structures of the 3,5-dimethylpyrazolyl bridged dirhodium complexes [Rh(μ-3,5-Me2pz)(CO)2]2 and [Rh(μ-3,5-Me2pz)(COD)]2 have been determined. Crystals of [Me2Gapz2]Rh(COD) are orthorhombic, a = 22.7447(8), b = 11.9776(5), c = 6.4635(3) Å, Z = 4, space group Pnma; those of [Rh(μ-3,5-Me2pz)(CO)2]2 are monoclinic, a = 8.7403(6), b = 16.3594(6), c = 25.434(2) Å, β = 95.286(3)°, Z = 8, space group P21/c; and those of [Rh(μ-3,5-Me2pz)(COD)]2 are triclinic, a = 10.350(2), b = 11.401(2), c = 12.355(2) Å, α = 112.485(7), β = 99.394(9), γ = 105.387(8)°, Z = 2, space group [Formula: see text]. All three structures were solved by conventional heavy atom techniques and were refined by full-matrix least-squares procedures to final conventional R values of 0.026, 0.024, and 0.037 for 1824, 5135, and 6109 reflections with I ≥ 3σ(I), respectively. In each case the Rh atoms have distorted square planar coordination geometry. Important mean structural parameters are Rh—N = 2.087(2), Rh—C = 2.129(2), [Formula: see text] for [Me2Gapz2]Rh(COD); Rh—N = 2.063(6), Rh—CO = 1.852(9), [Formula: see text] for [Rh(μ-3,5-Me2pz)(CO)2]2; and Rh—N = 2.084(1), Rh—C = 2.131(7), [Formula: see text] for [Rh(μ-3,5-Me2pz)(COD)]2.

Structure and magnetic properties of monophenylphosphinate bridged chain polymers of manganese(II), [MnL2(HPhPO2)2]x (where L = HPhPO2H, CH3CONH2, H2O, HCONH(CH3), and C5H5N)

1992 ◽  
Vol 70 (3) ◽  
pp. 732-741 ◽  
Author(s):  
Jing-Long Du ◽  
Steven J. Rettig ◽  
Robert C. Thompson ◽  
James Trotter ◽  
Peter Betz ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Heavy Atom ◽  
Indirect Evidence ◽  
Magnetic Coupling ◽  
Coupling Constants ◽  
Space Group ◽  
Linear Chains ◽  
Pyridine Complex ◽  
Square Planar ◽  
Neutral Ligands

Crystals of Mn(CH3CONH2)2(HPhPO2)2 are monoclinic, a = 5.668(2), b = 7.500(2), c = 23.104(2) Å, β = 95.52(2)°, Z = 2, space group P21/c, and those of Mn(HPhPO2H)2(HPhPO2)2 are monoclinic, a = 23.281(1), b = 5.508(2), c = 20.5489(6) Å, β = 90.424(4)°, Z = 4, space group C2/c. The structures were solved by heavy-atom methods and were refined by full-matrix least-squares procedures to R = 0.028 and 0.035 for 2081 and 2117 reflections with I ≥ 3σ(I), respectively. Both compounds have structures consisting of polymeric chains propagating along the crystallographic b axis; two phosphinate ligands bridge adjacent manganese atoms forming square planar MO4 units, and six coordination about the metal is achieved by axially O-bonded neutral ligands. Indirect evidence supports similar structures for the other complexes studied here. The complexes are antiferromagnetic and the magnetic susceptibilities have been analyzed according to two Heisenberg models for linear chains. The exchange coupling constants range from −0.30 cm−1 for the acetamide complex to −0.06 cm−1 for the pyridine complex. Magnetostructural correlations involving these complexes and the previously studied Mn(HCONH2)2(HPhPO2)2, reveal that the magnitude of the magnetic coupling is enhanced by symmetrically bridging O—P—O units and short Mn–O–P–O–Mn pathways for exchange. Keywords: polymeric manganese monophenylphosphinates, crystal structures, magnetic properties.

Conformation of azaphosphorinane ring. Crystal structures of 2,2,6,6-tetramethyl-4,4-diphenyl-1,4-azaphosphorinanium perchlorate and 2,2,6,6-tetramethyl-4-oxo-4-phenyl-1,4-azaphosphorinan-1-oxyl (stable nitroxy radical)

1983 ◽  
Vol 61 (3) ◽  
pp. 427-433 ◽  
Author(s):  
Miroslaw Cygler ◽  
Janusz Skolimowski
Keyword(s):  
Crystal Structures ◽  
Heavy Atom ◽  
Phenyl Group ◽  
Direct Methods ◽  
Chair Conformation ◽  
Monoclinic Space Group ◽  
Compound I ◽  
Orthorhombic Space Group ◽  
Space Group ◽  
Unit Cell Dimensions

Crystal structures of 2,2,6,6-tetramethyl-4,4-diphenyl-1,4-azaphosphorinanium perchlorate (I) and 2,2,6,6-tetramethyl-4-oxo-4-phenyl-1,4-azaphosphorinan-1-oxyl (II) were determined. Compound I crystallizes in the monoclinic space group C2/c with unit cell dimensions a = 18.2967(7), b = 10.9413(6), c = 20.8714(13) Å, β = 90.79(1)° (at 115 K), and II crystallizes in the orthorhombic space group Pn21a with a = 8.076(1), b = 10.139(1), c = 17.894(1) Å. Intensity data were measured on a diffractometer at 115 K for I and at the room temperature for II. The structures were solved by a combination of heavy-atom and direct methods and refined to R = 0.036 (3968 reflections) for I and 0.039 (1451 reflections) for II.The azaphosphorinane ring adopts a chair conformation in both molecules, being flattened in the P part in I and in the N part in II. In molecule I the equatorial phenyl group is nearly parallel to the approximate plane of symmetry of the molecule, and the axial phenyl group is perpendicular to that plane. In molecule II the P=O bond is axial and the phenyl group is equatorial. The CN(O)C group is not planar. The N—O bond makes an angle of 18.0(3)° with the CNC plane. The CNC angle of 129.3(3)° is larger than that found in nitroxypiperidine analogues.

Sign in / Sign up

Export Citation Format

Share Document