Synthesis and structural characterization of N,N′-diarylpiperazine N,N′-dioxide tetrahydrates (aryl = o-tolyl, p-tolyl, p-chlorophenyl)

1988 ◽  
Vol 66 (8) ◽  
pp. 1836-1847 ◽  
Author(s):  
Chun-Kiu Kwok ◽  
Thomas C. W. Mak
Keyword(s):  
Crystal Packing ◽  
Direct Method ◽  
Water Molecules ◽  
Compound I ◽  
Space Group ◽  
X Ray ◽  
A Site ◽  
Compound Ii

The synthesis and X-ray structure determination of N,N′-di(o-tolyl)piperazine N,N′-dioxide tetrahydrate, I, N,N′-di(p-tolyl)piperazine N,N′-dioxide tetrahydrate, II, and N,N′-di(p-chlorophenyl)piperazine N,N′-dioxide tetrahydrate, III, are described. Compound I crystallizes in space group [Formula: see text] with a = 7.778(1), b = 7.915(2), c = 8.919(2) Å, α = 106.25(2), β = 99.56(1), γ = 108.80(2)°, and Z = 1. Compound II crystallizes in space group [Formula: see text] with a = 6.558(1), b = 7.134(2), c = 11.610(3) Å; α = 73.23(2), β = 78.08(2), γ = 72.67(2)°, and Z = 1. Compound III crystallizes in space group P21/c with a = 9.159(3), b = 12.390(4), c = 8.339(4) Å, β = 97.38(3)°, and Z = 2. The structures of I–III were solved by the direct method and refined to R = 0.049 (1749 observed MoKα reflections), 0.055 (2651 observed reflections), and 0.035 (1827 observed reflections), respectively. In each case, the N,N′-dioxide molecule occupies a site of symmetry [Formula: see text]. The piperazine ring takes the chair form, with two N—O bonds oriented axially in a trans configuration. The structures are characterized by strong hydrogen bonding between the water molecules, as well as between the N-oxide groups and water molecules, giving rise to puckered layers composed of various combinations of edge-sharing four-membered, six-membered, ten-membered, and twelve-membered rings. The aryl rings, which protrude on both sides of each puckered layer, constitute hydrophobic regions separating the hydrophilic layers in the crystal packing.

scholarly journals Crystal structure determination of two pyridine derivatives: 4-[(E)-2-(4-methoxyphenyl)ethenyl]-1-methylpyridin-1-ium hexafluoro-λ6-phosphane and 4-[(E)-2-[4-(dimethylamino)phenyl]ethenyl]-1-phenyl-1λ5-pyridin-1-ylium hexafluoro-λ6-phosphane

2019 ◽  
Vol 75 (2) ◽  
pp. 288-291
Author(s):  
J. Arul Martin Mani ◽  
M. Mercina ◽  
S. Antony Inglebert ◽  
P. Narayanan ◽  
V. Joseph ◽  
...  
Keyword(s):  
Double Bond ◽  
Benzene Ring ◽  
Pyridine Ring ◽  
Crystal Packing ◽  
Pyridine Derivatives ◽  
Compound I ◽  
Π Interactions ◽  
Molecular Salts ◽  
Compound Ii

The title molecular salts, C16H16NO+·PF6 −, (I), and C21H21N2 +·PF6 −, (II), are pyridine derivatives. In compound (I), the cation comprises a methyl N-substituted pyridine ring and a methoxy-substituted benzene ring connected by a C=C double bond. The F atoms of the PF6 − anion are disordered over two sets of sites with refined occupancy factors of 0.614 (7):0.386 (7). In compound (II), the cation comprises a pyridine ring attached to unsubstituted phenyl ring and a dimethylaniline ring, which are connected by a C=C double bond. The anion is PF6 −. In both salts, the cation adopts an E configuration with respect to the C=C bond. The pyridine ring makes a dihedral angle of 9.86 (12)° with the methoxy-substituted benzene ring in compound (I) and 11.2 (3)° with the dimethylamine-substituted benzene ring in compound (II). In compound (I), the crystal packing is stabilized by weak C—H...F intermolecular interactions which result in R 4 3(14) ring motifs, forming molecular sheets running parallel to (\overline{1}03). These are further stabilized by weak P—F...π interactions. In compound (II), the crystal packing is stabilized by C—H...F interactions, which result in R 6 6(40) ring motifs, forming molecular sheets running parallel to (101) and these are further connected by π–π interactions.

Synthesis and X-ray powder diffraction characterization of tetra- and hexa-imidazole complexes of magnesium(II)

2008 ◽  
Vol 23 (4) ◽  
pp. 286-291 ◽  
Author(s):  
Norberto Masciocchi ◽  
Luigi Garlaschelli ◽  
Giulia Peli
Keyword(s):  
Powder Diffraction ◽  
Molecular Structures ◽  
Water Molecules ◽  
Powder Diffraction Data ◽  
Monoclinic System ◽  
Space Group ◽  
X Ray ◽  
Imidazole Complexes ◽  
Full Profile

X-ray powder diffraction data for two ionic salts containing imidazole (Him) complexes of the magnesium(II) ion, [Mg(Him)4(H2O)2]Cl2 and [Mg(Him)6](NO3)2, are reported. Their crystal and molecular structures were determined by simulated annealing and full-profile Rietveld refinement methods. [Mg(Him)4(H2O)2]Cl2 was found to crystallize in the monoclinic system with space group C2/c, a=12.3980(3) Å, b=11.0234(2) Å, c=14.4691(3) Å, and β=107.024(1)°. [Mg(Him)6](NO3)2 crystallizes in the trigonal R-3 space group with a=b=12.4631(4) Å and c=14.9449(6) Å. Both species contain centrosymmetric complexes, and Mg is octahedrally coordinated by six imidazoles, as in [Mg(Him)6](NO3)2, or by four imidazoles and two water molecules, as in [Mg(Him)4(H2O)2]Cl2. Additional analytic, thermogravimetric, calorimetric, and spectroscopic characterizations were also performed.

Synthesis and Structural Characterization of N,N´- Dipropyl-N,N,N´,N´-tetramethyl-1,2- ethylenediammonium Dichloride and Dibromide

2011 ◽  
Vol 66 (7) ◽  
pp. 755-758
Author(s):  
Sari M. Närhi ◽  
Janne Asikkala ◽  
Jatta Kostamo ◽  
Marja K. Lajunen ◽  
Raija Oilunkaniemi ◽  
...  
Keyword(s):  
Hydrogen Bonding ◽  
Water Molecules ◽  
Monoclinic Crystal System ◽  
X Ray Diffraction ◽  
Monoclinic Crystal ◽  
Triclinic Crystal System ◽  
Space Group ◽  
X Ray ◽  
Crystal System

N,N´-Dipropyl-N,N,N´ ,N´-tetramethyl-1,2-ethylenediammonium dichloride (1) and dibromide (2) were prepared by the reaction of N,N,N´,N´-tetramethyl-1,2-ethylenediamine and the corresponding 1-halopropane. The structures of the compounds were characterized by single-crystal X-ray diffraction. 1 · 2H2O crystallizes in the triclinic crystal system, space group P1, with Z = 1, and 2 in the monoclinic crystal system, space group P21/c, with Z = 2. The crystal structures of the salts consist of discrete dications and halide anions. The packing in 1 · 2H2O consists of layers of cations with the chloride anions and water molecules forming hydrogen-bonded chains between the cation layers. In 2, the strongest H· · ·Br hydrogen bonds of 2.8138(6) and 2.8187(7) °A link the cations and anions into doublestranded chains. In both salts, cations and anions are also linked together by a further weak C-H· · ·Cl/Br hydrogen bonding network.

Structural Systematics of Rare Earth Complexes. XII Solvated 1 : 1 Adducts of Some Lanthanoid(III) Carboxylates with 1,10-Phenanthroline and 2,2′:6′,2″-Terpyridine

1999 ◽  
Vol 52 (6) ◽  
pp. 481 ◽  
Author(s):  
Cameron J. Kepert ◽  
Lioubov I. Semenova ◽  
Lu Wei-Min ◽  
Brian W. Skelton ◽  
Allan H. White
Keyword(s):  
Rare Earth ◽  
Single Crystal ◽  
Structural Characterization ◽  
Structure Determination ◽  
Room Temperature ◽  
Water Molecules ◽  
X Ray ◽  
Structural Characterizations

A room-temperature single-crystal X-ray structure determination of the 1 : 1 adduct of 1,10-phenanthroline (`phen") with lutetium(III) acetate (as its dihydrate) is recorded. Crystals are triclinic, P 1, a 12·430(8), b 10·681(4), c 8·134(8) Å, α 74·76(6), β 84·81(7), γ 74·29(4)°, Z = 2 f.u.; conventional R on |F| was 0·031 for No 3939 independent ‘observed’ (I > 3σ(I)) diffractometer reflections. The complex [(N,N′-phen)(O,O′-ac)Lu(O-ac-O′)4Lu(O,O′-ac)(N,N′-phen)].2H2O is binuclear, the lutetium being eight-coordinated by bidentate phen and ac (acetate) ligands and four oxygen atoms from the bridging acetate ligands. Also recorded is the structural characterization of 1 : 1 Lu(ac)2Cl/tpy (tpy = 2,2′:6′,2″-terpyridine) as its pentahydrate; this complex is triclinic, P 1, a 12·410(3), b 11·559(4), c 9·976(4) Å, α 85·19(3), β 70·30(3), γ 65·70(2)°, Z = 2, R 0·049 for No 4717. The complex is shown to be [(tpy)(H2O)2Lu(O2CCH3)2]Cl.3H2O, with the lutetium nine-coordinated by tridentate tpy, a pair of bidentate acetates and two unidentate water molecules, with the chloride uncoordinated. Structural characterizations of a number of 1 : 1 adducts of variously solvated lanthanoid(III) trichloroacetates, Ln(tca)3, with tpy are also recorded. Yb(tca)3/tpy/MeOH (1 : 1 : 1) is triclinic, P 1, a 14·016(4), b 12·951(5), c 9·604(3) Å, α 73·89(3), β 76·56(3), γ 69·20(3)°, Z = 2 f.u., R 0·057 for No 4465. The complex is mononuclear, the eight-coordinate N3YbO5 array containing tridentate tpy, unidentate methanol, and two unidentate and one bidentate chelating anions. 1 : 1 : 1 Ln(tca)3/tpy/OH2 adducts for Ln = La(-)Nd are triclinic, P 1, a ≈ 13·4, b ≈ 12·47, c ≈ 11·5 Å, α ≈ 114·5, β ≈ 89·9, γ ≈ 115·6°, Z = 1 binuclear array, R 0·061, 0·071 for No 3240, 2394. The two Ln atoms are O,O′-bridged by a pair of anions, the N3LnO6 nine-coordinate lanthanoid environment being completed by a tridentate tpy, one water, one unidentate and one bidentate anion. A 1 : 1 : 1 Lu(tca)3/tpy/OH2 array, by contrast, is triclinic, P 1, a 16·569(8), b 14·815(5), c 14·375(6) Å, α 62·05(3), β 81·35(4), γ 77·97(3)°, Z = 4 ‘mononuclear’ f.u., R 0·067 for No 6710. The array, remarkably, contains species of both of the above types in a 1 : 2 binuclear-to-mononuclear ratio, but with water replacing methanol in the mononuclear array.

scholarly journals Two Crystal Forms of a Hydrated 2:1 β-Cyclodextrin Fluconazole Complex: Single Crystal X-ray Structures, Dehydration Profiles, and Conditions for Their Individual Isolation

Molecules ◽  
2021 ◽  
Vol 26 (15) ◽  
pp. 4427
Author(s):  
Andrea Sala ◽  
Zakiena Hoossen ◽  
Alessia Bacchi ◽  
Mino R. Caira
Keyword(s):  
Physicochemical Properties ◽  
Crystal Water ◽  
Crystal Forms ◽  
Space Group ◽  
X Ray ◽  
Pharmaceutical Ingredients ◽  
Crystallization Conditions ◽  
Water Contents

Inclusion complexes between cyclodextrins (CDs) and active pharmaceutical ingredients (APIs) have potential for pharmaceutical formulation. Since crystallization of a given complex may result in the isolation of multiple crystal forms, it is essential to characterize these forms with respect to their structures and physicochemical properties to optimize pharmaceutical candidate selection. Here, we report the preparation and characterization of two crystallographically distinct hydrated forms of an inclusion complex between β-cyclodextrin (β-CD) and the antifungal API fluconazole (FLU) as well as temperature–concentration conditions required for their individual isolation. Determination of crystal water contents was achieved using thermoanalytical methods. X-ray analyses revealed distinct structural differences between the triclinic (TBCDFLU, space group P1) and monoclinic (MBCDFLU, space group C2) crystal forms. Removal of the crystals from their mother liquors led to rapid dehydration of the MBCDFLU crystal, while the TBCDFLU crystal was stable, a result that could be reconciled with the distinct packing arrangements in the respective crystals. This study highlights (a) the importance of identifying possible multiple forms of a cyclodextrin API complex and controlling the crystallization conditions, and (b) the need to characterize such crystal forms to determine the extent to which their physicochemical properties may differ.

Zwitterionic and free forms of arylmethyl Meldrum's acids

2015 ◽  
Vol 71 (9) ◽  
pp. 752-758 ◽  
Author(s):  
Inese Mierina ◽  
Anatoly Mishnev ◽  
Mara Jure
Keyword(s):  
Crystal Packing ◽  
Building Blocks ◽  
Compound I ◽  
Molecular Conformations ◽  
X Ray ◽  
Methoxy Groups ◽  
Classical Hydrogen Bond ◽  
Meldrum's Acids ◽  
Compound Ii ◽  
Derivatives Of

C-Alkyl (including C-arylmethyl) derivatives of Meldrum's acids are attractive building blocks in organic synthesis, mainly due to the unusually high acidity of the resulting compounds. Three examples, namely 5-[4-(diethylamino)benzyl]-2,2-dimethyl-1,3-dioxane-4,6-dione, C17H23NO4, (I), 2,2-dimethyl-5-(2,4,6-trimethoxybenzyl)-1,3-dioxane-4,6-dione, C16H20O7, (II), and 5-(4-hydroxy-3,5-dimethoxybenzyl)-2,2-dimethyl-1,3-dioxane-4,6-dione, C15H18O7, (III), have been synthesized, characterized by NMR and IR spectroscopy, and studied by single-crystal X-ray structure analysis. The nature of the different substituents resulted in remarkable differences in both the molecular conformations and the crystal packing arrangements. The presence of a substituent with a basic centre in compound (I) leads to the formation of an inner salt accompanied by drastic changes in the conformation of the 1,3-dioxane-4,6-dione fragment. By virtue of strong N—H...O hydrogen bonds, the residues are assembled into infinite chains with the graph-set descriptorC(10). Compound (II) contains methoxy groups in both theortho- andpara-positions of the arylmethyl fragment. Because of the absence of classical hydrogen-bond donors in this structure, the crystal packing is controlled by van der Waals forces and weak C—H...O interactions. Compound (III) contains methoxy groups in bothmeta-positions and a hydroxy group in thepara-position. Supramolecular tetrameric synthons which comprise hydrogen-bonded dimers associated into tetramers through π–π interactions of overlapping benzene rings were observed.

scholarly journals Crystal and Molecular Structure of 7-Methyl-5,6,7,8-tetrahydro[1]benzothieno[2,3-d]pyrimidin-4[3H]one

2012 ◽  
Vol 9 (2) ◽  
pp. 525-531
Author(s):  
Mohamed Ziaulla ◽  
Afshan Banu ◽  
Shridhar I. Panchamukhi ◽  
Imtiyaz Ahmed M. Khazi ◽  
Noor Shahina Begum
Keyword(s):  
Molecular Structure ◽  
Crystal Structure ◽  
Crystal And Molecular Structure ◽  
Direct Method ◽  
Monoclinic Space Group ◽  
Space Group ◽  
X Ray ◽  
Π Interactions ◽  
R Factor

X-ray characterization of 7-methyl-5,6,7,8-tetrahydro[1]benzothieno [2,3-d]pyrimidin-4[3H]one is described. The compound crystallizes in the monoclinic space group P21/c with a=7.0013(2)Å, b=8.3116(3)Å, c=18.374(6)Å, β=91.746(2)°, V=1068.76(6)Å3, z=4. The structure was solved using the direct method and refined to reliability R-factor of 0.0639 using 3180 independent reflections The crystal structure is further stabilized by intermolecular C-H...N, N-H...N C-H...O, N-H...O, and π-π interactions.

Characterization of a Crystalline Residue From a Swimming Pool: Disodium Copper(II) Tetrakis(isocyanurate) Hexahydrate

1992 ◽  
Vol 45 (11) ◽  
pp. 1927 ◽  
Author(s):  
RD Hart ◽  
BW Skelton ◽  
AH White
Keyword(s):  
Chemical Analysis ◽  
Structure Determination ◽  
Title Compound ◽  
Swimming Pool ◽  
Water Molecules ◽  
Formula Unit ◽  
Sodium Ions ◽  
X Ray

Coupled with chemical analysis, a single-crystal X-ray structure determination of lilac deposit from a swimming pool, shows the deposit to be the title compound Na2Cu(C3H2N3O3)4.6H2O. Crystals are triclinic, P1, a 10.459(1), b 10.434(3), c 6.762(4) � , α: 71.73(4), β 83.67(4), γ 62.82(2), Z 1 formula unit; 1265 'observed' diffractometer reflections were refined to R 0.052. The copper atoms are located on crystallographic inversion centres, four-coordinated by a pair of water molecules [Cu-O, 1.937(6) � ] and a pair of ligand nitrogen atoms [Cu-N, 1.941(9) � ]. Interactions from ligand oxygen atoms to sodium ions link the structure into a polymeric array.

Structural Study of a new Compound Based on Acid 1,4-Cyclohexanedicarboxylic (1,4-CDC)

2010 ◽  
Vol 6 (1) ◽  
pp. 891-896
Author(s):  
Manel Halouani ◽  
M. Dammak ◽  
N. Audebrand ◽  
L. Ktari
Keyword(s):  
Aqueous Solution ◽  
Water Molecules ◽  
Carboxyl Group ◽  
X Ray Diffraction ◽  
Compound I ◽  
Unit Cell Parameters ◽  
Monoclinic System ◽  
X Ray ◽  
Cell Parameters ◽  
Cyclohexanedicarboxylic Acid

One nickel 1,4-cyclohexanedicarboxylate coordination polymers, Ni2 [(O10C6H4)(COO)2].2H2O  (I), was hydrothermally synthesized from an aqueous solution of Ni (NO3)2.6H2O, (1,4-CDC) (1,4-CDC = 1,4-cyclohexanedicarboxylic acid) and tetramethylammonium nitrate. Compound (I) crystallizes in the monoclinic system with the C2/m space group. The unit cell parameters are a = 20.1160 (16) Å, b = 9.9387 (10) Å, c = 6.3672 (6) Å, β = 97.007 (3) (°), V= 1263.5 (2) (Å3) and Dx= 1.751g/cm3. The refinement converged into R= 0.036 and RW = 0.092. The structure, determined by single crystal X-ray diffraction, consists of two nickel atoms Ni (1) and Ni (2). Lots of ways of which is surrounded by six oxygen atoms, a carboxyl group and two water molecules.

New Coordination Compounds of Fe(III) with Organic Ligands

2009 ◽  
Vol 59 (12) ◽  
Author(s):  
Mihaela Flondor ◽  
Ioan Rosca ◽  
Doina Sibiescu ◽  
Mihaela-Aurelia Vizitiu ◽  
Daniel-Mircea Sutiman ◽  
...  
Keyword(s):  
Chemical Analysis ◽  
Complex Compounds ◽  
Organic Ligands ◽  
X Ray Diffraction ◽  
X Ray ◽  
Elemental Chemical Analysis ◽  
Structural Formulae ◽  
Paramagnetic Properties

In this paper the synthesis and the study of some complex compounds of Fe(III) with ligands derived from: 2-(4-chloro-phenylsulfanyl)-1-(2-hydroxy-3,5-diiodo-phenyl)-ethanone (HL1), 1-(3,5-dibromo-2-hydroxy-phenyl)-2-phenylsulfanyl-ethanone(HL2), and 2-(4-chloro-phenylsulfanyl)-1-(3,5-dibromo-2-hydroxy-phenyl)-ethanone (HL3) is presented. The characterization of these complexes is based on method as: the elemental chemical analysis, IR and ESR spectroscopy, M�ssbauer, the thermogravimetric analysis and X-ray diffraction. Study of the IR and chemical analysis has evidenced that the precipitates form are a complexes and the combination ratio of M:L is 1:2. The central atoms of Fe(III) presented paramagnetic properties and a octaedric hybridization. Starting from this precipitation reactions, a method for the gravimetric determination of Fe(III) with this organic ligands has been possible. Based on the experimental data on literature indications, the structural formulae of the complex compounds are assigned.

Sign in / Sign up

Export Citation Format

Share Document