scholarly journals Success or Failure of Chiral Crystallization of Similar Heterocyclic Compounds

Molecules ◽  
2020 ◽  
Vol 25 (23) ◽  
pp. 5691
Author(s):  
Cyprian M. Chunkang ◽  
Iris E. Ikome ◽  
Emmanuel N. Nfor ◽  
Yuta Mitani ◽  
Natsuki Katsuumi ◽  
...  
Keyword(s):  
Hydrogen Bonds ◽  
Single Crystal ◽  
Single Crystals ◽  
Heterocyclic Compounds ◽  
Van Der Waals ◽  
Van Der Waals Forces ◽  
The Other ◽  
X Ray ◽  
Other Hand

Single crystals of two achiral and planar heterocyclic compounds, C9H8H3O(CA1) and C8H5NO2 (CA4), recrystallized from ethanol, were characterized by single crystal X-ray analysis, respectively, and chiral crystallization was observed only for CA1 as P212121 (# 19), whereas it was not observed for CA4 P21/c (# 14). In CA1, as a monohydrate, the hydrogen bonds were pronounced around the water of crystallization (O4), and the planar cyclic sites were arranged in parallel to slightly tilted positions. On the other hand, an anhydride CA4 formed a dimer by hydrogen bonds between adjacent molecules in the crystal, which were aggregated by van der Waals forces and placed in parallel planar cyclic sites.

Variable-temperature neutron diffraction studies of the short, strong N...O hydrogen bonds in the 1:2 co-crystal of benzene-1,2,4,5-tetracarboxylic acid and 4,4'-bipyridyl

2003 ◽  
Vol 59 (6) ◽  
pp. 794-801 ◽  
Author(s):  
John A. Cowan ◽  
Judith A. K. Howard ◽  
Garry J. McIntyre ◽  
Samuel M.-F. Lo ◽  
Ian D. Williams
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonds ◽  
Neutron Diffraction ◽  
Single Crystal ◽  
Variable Temperature ◽  
Intermediate Position ◽  
The Other ◽  
Tetracarboxylic Acid ◽  
Other Hand

The 1:2 adduct of benzene-1,2,4,5-tetracarboxylic acid and 4,4′-bipyridyl at 100 K has been studied by single-crystal neutron diffraction at 20, 200 and 296 K. The structure contains two short, strong N...O hydrogen bonds: one O—H...N hydrogen bond [O...N 2.6104 (17) Å at 20 K] and one short N—H...O hydrogen bond [N...O 2.5220 (17) Å at 20 K]. The N—H distance in the N—H...O hydrogen bond changes from 1.207 (3) Å at 20 K to 1.302 (4) Å at 296 K and the N...O distance increases to 2.5315 (16) Å at 296 K. At 200 K the H atom lies in an intermediate position 1.251 (6) Å from the N atom with an N...O separation of 2.520 (4) Å. The O—H...N hydrogen bond, on the other hand, does not change with temperature.

scholarly journals On the interpretation of X-ray, single crystal, rotation photographs

1926 ◽  
Vol 113 (763) ◽  
pp. 117-160 ◽  
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
The Other ◽  
X Rays ◽  
X Ray ◽  
Powder Method ◽  
Convenient Form ◽  
Other Hand ◽  
Rotation Method ◽  
Laue Method

In the development of the study of crystals by X-rays the methods used divide themselves naturally into four types : the Bragg Ionisation Spectrometer method, the Laue method, the Powder method of Debye and Scherrer, and the Rotating Crystal method of Rinne, Schiebold and Polyani. The techniques of the first three of these methods are fully explained in such books as ‘ X-Rays and Crystal Structure,’ by W. H. and W. L. Bragg, ‘ The Structure of Crystals,’ by Wyckoff, and ‘ Krystalle und Rontgenstrahlen,’ by Ewald, as well as in original papers. On the other hand, the rotation method is only slightly touched on in these works, the literature is scattered in a great number of papers, and the technique has not so far been described at any length in a convenient form. Particularly in English, references to it are scanty. In this paper the author has tried to give a concise account of the method, together with various types of charts and tables as it is used in the Davy Faraday Laboratory. The methods described differ in certain respects from those used on the Continent,* but they have been found to be rapid and sufficiently accurate.

Structural and spectroscopic studies of dipotassium 3,3,3′,3′-tetramethylcystinate trihydrate, K2[C10H18N2O4S2]3H2O

1984 ◽  
Vol 62 (6) ◽  
pp. 1127-1133 ◽  
Author(s):  
Romolo Faggiani ◽  
Helen Elaine Howard-Lock ◽  
Colin James Lyne Lock ◽  
Maria Lurdes Martins ◽  
Philip Stuart Smalley
Keyword(s):  
Hydrogen Bonds ◽  
Single Crystal ◽  
Spectroscopic Studies ◽  
The Other ◽  
Ionic Interactions ◽  
Water Molecules ◽  
Torsional Angle ◽  
X Ray Diffraction ◽  
Standard Methods ◽  
X Ray

The compound dipotassium 3,3,3′,3′-tetramethylcystinate trihydrate, K2[C10H18O4N2S2]3H2O, has been prepared and characterized by single crystal X-ray diffraction. Crystals were monoclinic, P21a = 6.160(1), b = 26.473(8), c = 6.193(1) Å, β = 113.94(1)°, with two formula units in the unit cell. Intensities were measured on a Syntex P21, diffractometer with use of MoKα radiation. The structure was solved by standard methods and refined to R1 = 0.0469, R2 = 0.0472 based on 2303 independent observed reflections. The C—S bonds (1.877(6), 1.891(6) Å) are longer than in many similar compounds although the S—S bond (2.040(2) Å) is not. The C—S—S—C torsional angle (108.7(3)°) is larger than normal in dithiol compounds. Other distances and angles are normal. Two types of potassium coordination are present, one a distorted octahedron, the other a distorted trigonal prism. In addition to the ionic interactions, hydrogen bonds involving the water molecules are important in stabilizing the structure.

Darstellung und Strukturbeschreibung von NaCa3 Mn(V2O7)(V3O10) / Preparation and Structure of NaCa3Mn(V2O7)(V3O10)

1998 ◽  
Vol 53 (5-6) ◽  
pp. 507-511 ◽  
Author(s):  
R. Rettich ◽  
Hk. Müller-Buschbaum
Keyword(s):  
Single Crystal ◽  
Single Crystals ◽  
Argon Atmosphere ◽  
Statistical Distribution ◽  
The Other ◽  
Space Group ◽  
X Ray ◽  
Point Position ◽  
Symmetry Space ◽  
Symmetry Space Group

Abstract Single crystals of NaCa3 Mn(V2O7)(V3O10) have been prepared by crystallization from flux in argon atmosphere. X-Ray single crystal methods led to triclinic symmetry, space group C1i - P 1̄, a = 6.8798(9), b = 6.902(1), c = 15.480(2) Å, α = 87.39(1), β = 85.32(1), γ = 86.25(2) °, Z = 2. The compound belongs to the rare trivanadates showing V2O7 and V3O10 groups incorporated into a NaCaMn/O framework. One point position of the cations is occupied by Ca2+, three by Na+ and Ca2+ in a statistical distribution and a fourth one by Mn2+. The surrounding of Mn2+ and the statistically occupied position M(3) are octahedra, the other metal positions are centers of capped trigonal prisms.

Molekül-und Kristallstrukturen des Dibrom- und Dijodmaleinsäurethioanhydrids Zum Verständnis der Korrelation zwischen / Crystal Structures of Dibrom- and Diiod Maleic Acid Thioanhydride

1980 ◽  
Vol 35 (1) ◽  
pp. 14-17 ◽  
Author(s):  
Walter Gonschorek
Keyword(s):  
Single Crystal ◽  
Crystal Structures ◽  
Maleic Acid ◽  
Van Der Waals ◽  
Van Der Waals Forces ◽  
Space Group ◽  
X Ray ◽  
Lattice Constants ◽  
Molecular And Crystal Structures

Abstract The molecular and crystal structures of dibrom maleic acid thioanhydride and diiod maleic acid thioanhydride have been determined by means of single-crystal X-ray intensities. The crystal structures are isomorphous and have the space group P41212 (enantiomorphous with P43212). The lattice constants are a = 7.543 Å, c = 12.155 Å (DBMTA) and a = 7.816 Å, c = 12.348 Å (DIMTA). The five-membered rings of the molecules are planar with maximum deviations of 0.003 Å (DBMTA) and 0.005 Å (DIMTA). Adjacent molecules are held together by van-der-Waals-forces.

Thermolysis of Some Spirobenzopyran-3’,2-[1,3,4]oxadithiino- [5,6-c]benzopyran-4’-ones in the Presence of Some Homodienes and Crystallographic Studies of Some Adducts

2006 ◽  
Vol 61 (11) ◽  
pp. 1413-1420 ◽  
Author(s):  
Mohamed I. Hegab ◽  
A. M. Moustafa
Keyword(s):  
Single Crystal ◽  
The Other ◽  
X Ray Diffraction ◽  
X Ray ◽  
Other Hand ◽  
Good Support

The very reactive α-oxo-thioketone derivatives 2a - d, generated via thermolysis of spirobenzopyran- 3’,2-[1,3,4]oxadithiino[5,6-c]benzopyran-4’-ones 1a - d, reacted with 2,3-dimethyl-1,3-butadiene and 1,3-cyclohexadiene under [4+2]-cycloaddition to afford spirobenzopyran-3’,6-thiapyran-4’-one adducts 3a - d and spirobenzopyran-3’,3-thiabicyclo[2.2.2]oct-5-en-4’-one adducts 4a - d, respectively. On the other hand, the reaction of α-oxo-thioketones 2a - d with isoprene afforded regioselectively only 3-methyl-thiapyran derivatives 5a - d. Single crystal X-ray diffraction studies of 4b, 4c, and 5a give a good support for the established structure.

Säure-Base-Eigenschaften des zyklischen Triamins N,N′,N″-Trimethyl-1,4,7-triazacyclononan: Die Kristallstruktur seiner monoprotonierten Form [C9H22N3]ClO4) / Acid-Base Properties of the Cyclic Triamine N,N′,N″-Trimethyl-1,4,7-triazacyclononane and Crystal Structure of its Monoprotonated Form [C9H22N3](ClO4)

1987 ◽  
Vol 42 (3) ◽  
pp. 279-281 ◽  
Author(s):  
K. Wieghardt ◽  
S. Brodka ◽  
K. Peters ◽  
E. M. Peters ◽  
A. Simon
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonds ◽  
Single Crystal ◽  
The Other ◽  
X Ray Diffraction ◽  
Acid Base ◽  
Amine Nitrogen ◽  
X Ray ◽  
Acidic Proton ◽  
Proposed Model

The crystal structure of the monohydroperchlorate of N,N',N"-trimethyl-1,4,7-triazacyclo-nonane, [C9H22N3](ClO4), has been determined by single crystal X-ray diffraction. The acidic proton of the cation is bonded to one amine nitrogen and it forms hydrogen bonds to the other two N-atoms in agreement with a proposed model, which has been invoked to interpret successive protonation constants of cyclic triamines. The salt [Me6[9]aneN3](BF4)3 has also been prepared

Crystal and Molecular Structure of cis-2,2',3',2"-Tetraacetoxy-1,1':4',1"-ternaphthyl

1996 ◽  
Vol 61 (5) ◽  
pp. 726-732
Author(s):  
Jaroslav Podlaha ◽  
Ivana Císařová ◽  
Martin Bělohradský ◽  
Jiří Závada
Keyword(s):  
Molecular Structure ◽  
Single Crystal ◽  
Title Compound ◽  
Crystal And Molecular Structure ◽  
Van Der Waals ◽  
Van Der Waals Forces ◽  
X Ray Diffraction ◽  
X Ray ◽  
The Mean ◽  
Configuration And Conformation

The configuration and conformation of the title compound as a representative of conformationally locked ternaphthyls was determined by single-crystal X-ray diffraction. The arrangement of the mean planes of naphthyl and acetoxy groups results from intramolecular van der Waals forces.

ScOH(CH3SO3)2, a Basic Methanesulfonate of Scandium with Chain Structure

2004 ◽  
Vol 59 (1) ◽  
pp. 33-36 ◽  
Author(s):  
Mathias S. Wickleder ◽  
Ingrid Müller
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonds ◽  
Single Crystal ◽  
Single Crystals ◽  
Structure Determination ◽  
Ir Spectrum ◽  
Methanesulfonic Acid ◽  
Chain Structure ◽  
Orthorhombic Space Group ◽  
X Ray

Abstract Single crystals of ScOH(CH3SO3)2 were obtained from a solution of Sc2(CO3)3 in methanesulfonic acid at pH 7. According to the X-ray single crystal structure determination, the compound crystallizes with the non-centrosymmetric orthorhombic space group Pmc21 (Z = 8, a = 743.92(8), b = 1497.7(3), c = 1540.1(2) pm, Rall = 0.0925) and contains the Sc3+ ions in octahedral coordination of oxygen atoms which belong to two OH− and four CH3SO3 − ions. The linkage of the Sc3+ ions leads to chains according to the formulation 1∞[Sc(CH3SO3)4/2(OH)2/2] which are oriented along the [100] direction and connected via hydrogen bonds. The IR spectrum of the compound shows the typical bands of the CH3SO3 − ion.

scholarly journals X-ray crystal structure of trans-bis(pyridin-3-yl)ethylene: comparing the supramolecular structural features among the symmetrical bis(n-pyridyl)ethylenes (n = 2, 3, or 4) constitutional isomers

2020 ◽  
Vol 76 (12) ◽  
pp. 1859-1862
Author(s):  
Jay Quentin ◽  
Eric W. Reinheimer ◽  
Leonard R. MacGillivray
Keyword(s):  
Molecular Structure ◽  
Crystal Structure ◽  
Hydrogen Bonds ◽  
Single Crystal ◽  
Structural Features ◽  
The Other ◽  
Two Dimensional ◽  
X Ray Diffraction ◽  
X Ray ◽  
Packing Assembly

The molecular structure of trans-bis(pyridin-3-yl)ethylene (3,3′-bpe), C12H10N2, as determined by single-crystal X-ray diffraction is reported. The molecule self-assembles into two dimensional arrays by a combination of C—H...N hydrogen bonds and edge-to-face C—H...π interactions that stack in a herringbone arrangement perpendicular to the crystallographic c-axis. The supramolecular forces that direct the packing of 3,3′-bpe as well as its packing assembly within the crystal are also compared to those observed within the structures of the other symmetrical isomers trans-1,2-bis(n-pyridyl)ethylene ( n , n ′-bpe, where n = n′ = 2 or 4).

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