X-Ray Structural Studies of Small-Bite Ligands on Large Cations – Lanthanide(III) Ions and Dimethylphosphate

2020 ◽  
Vol 73 (6) ◽  
pp. 539 ◽  
Author(s):  
Eric J. Chan ◽  
Jack M. Harrowfield ◽  
Brian W. Skelton ◽  
Allan H. White
Keyword(s):  
Single Crystal ◽  
Structural Studies ◽  
X Ray ◽  
Structural Characterisation ◽  
The Third ◽  
Lanthanide Series ◽  
Binuclear Species ◽  
Lighter Lanthanides

Reactions of lanthanide chlorides or trifluoracetates (tfa) or picrates with trimethylphosphate alone in the first two cases or trimethylphosphate plus 1,10-phenanthroline or 2,2′;6′,2′′-terpyridine in the third, result in the formation of crystalline products containing dimethylphosphate (dmp–). Single crystal X-ray structural characterisation of these materials has shown that the stoichiometrically simple Ln(dmp)3 species obtained with chloride reactants and the lighter lanthanides are polymeric and commonly dimorphic, while the stoichiometrically more variable mixed dmp/tfa complexes have structures closely related to one phase of the Ln(dmp)3 family, and the presence of picrate and aza-aromatic ligands enables the isolation of Y and Lu derivatives containing binuclear species. In all, the dmp– ligands adopt exclusively the κ1O;κ1O′ bridging mode, the overall results indicating that this should apply to the complete lanthanide series.

Lewis-Base Adducts of Lead(II) Compounds. XVI. Synthetic and Structural Studies of Some Adducts of 2-Aminomethylpyridine With Lead(II) Compounds

1996 ◽  
Vol 49 (10) ◽  
pp. 1127 ◽  
Author(s):  
JM Harrowfield ◽  
H Miyamae ◽  
BW Skelton ◽  
AA Soudi ◽  
AH White
Keyword(s):  
Single Crystal ◽  
Room Temperature ◽  
Lewis Base ◽  
Structural Studies ◽  
Problem Structure ◽  
Coordination Environment ◽  
X Ray ◽  
The Third ◽  
Structure Determinations ◽  
Centrosymmetric Dimers

Syntheses and room-temperature single-crystal X-ray structure determinations are recorded for 2:1 adducts of 2-aminomethylpyridine ('amp') with lead(II) nitrate and thiocyanate . [(amp)2Pb(NO3)2]2 is triclinic, Pī, a 11.616(4), b 11.145(6), c 7.341(3) Ǻ, α 83.87(4), β 89.17(3), γ 64.12(3)°, Z = 1 dimer ; R was 0.043 for No 3529 independent 'observed' (I > 3σ(I)) reflections. [(amp)2Pb(SCN)2]2 is also triclinic, Pī , a 12.121(9), b 9.301(14), c 8.615(8) Ǻ, α 70.11(10), β 84.00(7), γ 79.38(10)°, Z = 1 dimer (R 0.033 for No 3467). Both complexes are centrosymmetric dimers ; the coordination environment is made up in each case of a pair of N,N°-bidentate bases, one terminally bound anion (O,O°-chelating nitrate or S-bonded thiocyanate ) and bridging anions. In the case of the thiocyanates, these bridge end-on, so that the lead(II) environment is seven-coordinate PbN5S2; in the nitrate, the anion chelates through two of its oxygen atoms, bridging via the third, so that the lead(II) environment is nine-coordinate PbN4O5. A 'problem structure', [(amp)2Pb(ClO4)2], monoclinic, C2/c (?), a 14.528(3), b 8.203(3), c 15.495(6) Ǻ, β 91.14(3)°, Z = 4 f.u ., R 0.044 for No 1775, is also recorded, the crystal seemingly a disordered aggregate of [(N, N′-amp)2Pb(OClO3)2] moieties.

Lewis-Base Adducts of Lead(II) Compounds. XVIII. Synthetic and Structural Studies of Some 1:1 and 2:1 Adducts of 2,4,6-Tris (2-pyridyl)-1,3,5-triazine With Lead(II) Nitrate

1996 ◽  
Vol 49 (10) ◽  
pp. 1147 ◽  
Author(s):  
JM Harrowfield ◽  
DL Kepert ◽  
H Miyamae ◽  
BW Skelton ◽  
AA Soudi ◽  
...  
Keyword(s):  
Single Crystal ◽  
Polymer Chain ◽  
Room Temperature ◽  
Lewis Base ◽  
Lead Atom ◽  
Structural Studies ◽  
Complex Species ◽  
X Ray ◽  
The Third ◽  
Metal Ligand

Adducts of lead(II) nitrate with 2,4,6-tris(2-pyridyl)-1,3,5-triazine (' trz ') have been synthesized and structurally characterized by room-temperature single-crystal X-ray studies, for 1:1 and 1:2 stoichiometry. Crystals of [( trz ) Pb (NO3)2](∞|∞) are monoclinic, P 21/c, a 10.531 (1), b 12.856(2), c 16.874(3) Ǻ, β 102.83(1)°, Z = 4 f.u .; R was 0.027 for No = 2773 'observed' (I > 3σ(I)) reflections. The complex is an infinite polymer; the plane of the tridentate trz ligand lies normal to the polymer axis ( Pb -N(central; distal) 2.523(5); 2.594(5), 2.568(5) Ǻ) with unsymmetrically bidentate nitrate groups to either side ( Pb -O 2.598(6), 2.928(7); 2.556(6), 2.911(7) Ǻ). The third oxygen of each nitrate group bridges to the next lead atom in the polymer chain ( Pb -O 3.008(5), 3.083(6)Ǻ). [( trz )2Pb(NO3)2] is monoclinic, C 2/c, a 15.723(5), b 10.034(2), c 24.379(15) Ǻ, β 106.84(4)°, Z = 4 f.u .; R was 0.038 for No 3030. The compound is a methanol monosolvate. The complex species is mononuclear, with the lead atom located on a crystallographic 2 axis and 10-coordinated by pairs of symmetry-related tridentate trz ( Pb -N(central; distal) 2.779(4); 2.800(5), 2.818(5) Ǻ) and bidentate nitrate ligands ( Pb -O 2.796(6), 2.689(5)Ǻ). A hexahydrate has also been obtained (triclinic, Pī a 23.580(9), b 10.147(4), c 9.762(4)Ǻ, α 113.14(3), β 92.11(3), γ 101.60(3)°, Z = 2 f.u ; R 0.041 for No 5633); although metal-ligand distances are similar to those found in the methanol solvate, and quasi-2 symmetry is retained, a very different stereochemistry is evident in respect of the relative dispositions of the ligands about the (quasi)-2 axis, involving a substantial twist of the two nitrate ligands relative to the triazines, and a flattening of the latter. The coordination polyhedron is different in the two 1:2 adducts. In the methanol solvate the stereochemistry is pentagonal antiprismatic whereas in the hexahydrate it is bicapped square antiprismatic.

Die Kristallstrukturen der isotypen Verbindungen Ba3[MoN4] und Ba3[WN4] / The Crystal Structures of the Isotypic Compounds Ba3[MoN4] and Ba3[WN4]

1991 ◽  
Vol 46 (5) ◽  
pp. 566-572 ◽  
Author(s):  
Axel Gudat ◽  
Peter Höhn ◽  
Rüdiger Kniep ◽  
Albrecht Rabenau
Keyword(s):  
Transition Metals ◽  
Single Crystal ◽  
Crystal Structures ◽  
Structure Type ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ternary Compounds ◽  
The Third

The isotypic ternary compounds Ba3[MoN4] and Ba3[WN4] were prepared by reaction of the transition metals with barium (Ba3N2, resp.) under nitrogen. The crystal structures were determined by single crystal X-ray diffraction: Ba3[MoN4] (Ba3[WN4]): Pbca; Z = 8; a = 1083.9(3) pm (1091.8(3) pm), b = 1030.3(3) pm (1037.5(3) pm), c = 1202.9(3) pm (1209.2(4) pm). The structures contain isolated tetrahedral anions [MN4]6- (M = Mo, W) which are arranged in form of slightly distorted hexagonal layers and which are stacked along [010] with the sequence (···AB···). Two of the three Ba atoms are situated between, the third one is placed within the layers of [MN4]-groups. In this way the structures can be derived from the Na3As structure type.

Comparative Structural Studies on Three-Coordinate Copper(I) Halide Complexes With Tertiary Phosphines. Crystal Structures of [(PPh2Mes)CuX]2 and [(PPhMes2)CuX]2 (Mes = Mesityl X = Cl, Br, I)

1992 ◽  
Vol 45 (7) ◽  
pp. 1155 ◽  
Author(s):  
GA Bowmaker ◽  
D Camp ◽  
RD Hart ◽  
PC Healy ◽  
BW Skelton ◽  
...  
Keyword(s):  
Single Crystal ◽  
Crystal Structures ◽  
Copper Atom ◽  
Structural Studies ◽  
Coordination Environment ◽  
X Ray ◽  
Tertiary Phosphines ◽  
Structure Determinations ◽  
Halide Complexes ◽  
The Subject

The 1 : 1 complexes of the substituted triphenylphosphine ligands mesityldiphenylphosphine and dimesitylphenylphosphine with copper(1) chloride, bromide and iodide have been the subject of single-crystal X-ray structure determinations at 295 K. All six complexes crystallize as air-stable dimeric molecules, [(PPh2Mes)CuX]2 and [ (PPhMes2)CUX]2 with each copper atom in a distorted trigonal PCuX2. coordination environment. Crystals of [(PPh2Mes)CuCl]2 (1) are monoclinic, P21/n, a 9.961(3), b 18.687(6), c 11.009(7) Ǻ, β 114.63(4)°; R was 0.049 for 2450 'observed' reflections. [(PPh2Mes)CuBrI2 (2) is monoclinic, P21/n, a 9.939(2), b 18.832(6), c 11.238(6) Ǻ, β 115.36(3)°; R was 0.046 for 1803 'observed' reflections. [(PPh2Mes)CuI]2.4/3 C6H6 (3) is rhornbohedral, R3, a 36.877(8), c 9.047(5) A; R was 0.039 for 2537 'observed' reflections. Crystals of [(PPhMes2)CuCl]2.2MeCN (4) are triclinic, Pi, a 15.783(7), b 9.570(4), c 8.914(4) Ǻ, α 72.43(3), β 76.37(3), γ 74.03(3)°; R was 0.045 for 3341 'observed' reflections. [(PPhMes2)CuBr]2.3C6H6 (5) is monoclinic, C2/c, a 9.694(6), b 30.15(2), c 20.66(2) Ǻ, β 98.00(7)°; R was 0.047 for 2117 'observed' reflections. [(PPhMes2)CuI]2.2MeCN (6) is orthorhombic, PP1nb, a 11.694(8), b 14.77(1), c 29.76(3) Ǻ; R was 0.049 for 3447 'observed' reflections. Cu-P bond lengths are: 2.196(2) A (1); 2.198(3) Ǻ (2); 2.222(5) and 2.226(5) Ǻ (3); 2.202(1) Ǻ (4); 2.197(3) A (5); 2.201(4) and 2.264(5) Ǻ (6). The geometries of the LCuX2 and CuX2Cu units are compared with data reported for other monomeric and dimeric compounds for both phosphorus- and nitrogen-based ligands L.

Studies of Australian soft corals. XXXII. The structure determination of degraded xenicin-type diterpenes from several Efflatounaria species

1983 ◽  
Vol 36 (11) ◽  
pp. 2279 ◽  
Author(s):  
BF Bowden ◽  
JC Coll ◽  
VA Patrick ◽  
DM Tapiolas
Keyword(s):  
Single Crystal ◽  
Chemical Transformation ◽  
Structure Determination ◽  
High Field ◽  
Soft Corals ◽  
X Ray ◽  
The Third

Three new diterpenes have been isolated from soft corals of the genus Efflatounaria (Coelenterata, Octocorallia, Alcyonacea, Xeniidae). The structure of the first compound (4) was elucidated on the basis of high-field 1H n.m.r. spectroscopy while that of the second metabolite (5) was determined by single-crystal X-ray analysis. The third diterpene (6) was structurally related to (5), and its structure was confirmed by chemical transformation. All three diterpenes can be derived from xenicin-type precursors, by cleavage and recyclization.

Polypyridines, Picrates, Lanthanides: A Plethora of Stacks?

2020 ◽  
Vol 73 (6) ◽  
pp. 529
Author(s):  
Eric J. Chan ◽  
Simon A. Cotton ◽  
Jack M. Harrowfield ◽  
Brian W. Skelton ◽  
Alexandre N. Sobolev ◽  
...  
Keyword(s):  
Nitro Group ◽  
The Other ◽  
Molar Ratio ◽  
Lanthanide Ion ◽  
X Ray ◽  
The Third ◽  
Group Oxygen ◽  
Structure Determinations ◽  
Lighter Lanthanides ◽  
Trigonal Prismatic

Reactions of the lanthanide(iii) picrates (picrate=2,4,6-trinitrophenoxide=pic) with 1,10-phenanthroline (phen) and 2,2′:6′,2′′-terpyridine (terpy) in a 1:2 molar ratio have provided crystals suitable for X-ray structure determinations in instances predominantly involving the lighter lanthanides. In all, the aza-aromatic ligands chelate the lanthanide ion, none being found as ‘free’ ligands within the lattice. The complexes of 1,10-phenanthroline have been characterised in two forms, one unsolvated (Ln=La, Sm, Eu; monoclinic, C2/c, Z 8), one an acetonitrile monosolvate (Ln=Gd; monoclinic, P21/a, Z 4), the latter being the only previously known form (with Ln=La). In both forms, the LnIII is nine-coordinate, in an approximately tricapped trigonal-prismatic environment, with two picrate ligands chelating through phenoxide and 2-nitro group oxygen atoms, the third being bound through phenoxide-O only. The 2,2′:6′,2′′-terpyridine complexes, all acetonitrile monosolvates defined for Ln=La, Gd, Er, and Y (monoclinic, C2/c, Z 4), are ionic, one picrate having been displaced from the primary coordination sphere. For Ln=La, the two bound picrates are again chelating, making the LaIII 10-coordinate in a distorted bicapped square-antiprismatic environment but in the other species they are bound through phenoxide-O only, making the LnIII ions eight-coordinate in a distorted square-antiprismatic environment. Stacked arrays of the ligands can be found in both series of complexes, with intramolecular picrate–picrate and picrate–aza-aromatic stacks being prominent features.

Optical, electrical, and X-ray-structural studies on Verneuil-grown SrTiO3 single crystal: Annealing study

2007 ◽  
Vol 401-402 ◽  
pp. 433-436 ◽  
Author(s):  
S. Mochizuki ◽  
F. Fujishiro ◽  
K. Shibata ◽  
A. Ogi ◽  
T. Konya ◽  
...  
Keyword(s):  
Single Crystal ◽  
Structural Studies ◽  
X Ray ◽  
Annealing Study
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