Control of the Mode of Polymorphic Transition Inducing Preferential Enrichment by Modifying the Molecular Structure or Adding Seed Crystals: Significant Influence of CH/F Hydrogen Bonds

2008 ◽  
Vol 8 (2) ◽  
pp. 540-548 ◽  
Author(s):  
Masahiro Horiguchi ◽  
Shinichiro Okuhara ◽  
Eiji Shimano ◽  
Daisuke Fujimoto ◽  
Hiroki Takahashi ◽  
...  
Keyword(s):  
Molecular Structure ◽  
Hydrogen Bonds ◽  
Significant Influence ◽  
Polymorphic Transition ◽  
Seed Crystals

Synthesis, crystal and molecular structure, and vibrational spectra of the complex (COOH)2•2H2O•18-crown-6

1986 ◽  
Vol 64 (1) ◽  
pp. 142-147 ◽  
Author(s):  
Suzanne Deguire ◽  
François Brisse ◽  
Jacques Ouellet ◽  
Rodrigue Savoie
Keyword(s):  
Molecular Structure ◽  
Hydrogen Bonds ◽  
Oxalic Acid ◽  
Raman Spectra ◽  
Vibrational Spectra ◽  
Crystal And Molecular Structure ◽  
Unit Cell ◽  
Infrared And Raman Spectra ◽  
O 18 ◽  
Stoichiometric Complex

A stoichiometric complex of formula (COOH)2•2H2O•18-crown-6 has been obtained from oxalic acid and the macrocyclic polyether 18-crown-6. The crystals of the complex have a monoclinic unit cell and belong to the P21/c space group. The components in the adduct are linked through hydrogen bonds in a polymer-like fashion: -crown–H2O–HOOCCOOH–OH2–crown–, where the oxalic acid molecules are present in two distinct disordered orientations. The infrared and Raman spectra of the complex are also reported and interpreted.

Crystal and molecular structure of diorganoammonium oxalatotrimethylstannate, [R2NH2][Me3Sn(C2O4)] (R=i-Bu, cyclohexyl)

2011 ◽  
Vol 34 (5-6) ◽  
pp. 127-130 ◽  
Author(s):  
Yaya Sow ◽  
Libasse Diop ◽  
Kieran C. Molloy ◽  
Gabrielle Kociok-Köhn
Keyword(s):  
Molecular Structure ◽  
Hydrogen Bonds ◽  
Diffraction Study ◽  
Crystal And Molecular Structure ◽  
X Ray Diffraction ◽  
X Ray ◽  
Trigonal Bipyramidal ◽  
Trans Complex ◽  
A Chain ◽  
Distorted Trigonal Bipyramidal

Abstract The title compounds [R2NH2][C2O4SnMe3](R=i-Bu, Cy), in which tin atoms adopt a distorted trigonal bipyramidal configuration, have been prepared and submitted to an X-ray diffraction study. These compounds have been obtained from the reaction of (Cy2NH2)2C2O4·H2O or (i-Bu2NH2)2C2O4 with SnMe3Cl. In both [R2NH2][C2O4SnMe3] compounds, the trans complex has an almost regular trigonal bipyramidal geometry around the tin atom. The SnMe3 residues are connected as a chain with bridging oxalate anions in a trans-SnC3O2 framework, the oxygen atoms being in axial positions. The cations connect linear adjacent chains through NH…O hydrogen bonds giving layered structures.

3-Bromo-2-bromomethyl-1-phenylsulfonyl-1H-indole

2007 ◽  
Vol 63 (3) ◽  
pp. o1521-o1522
Author(s):  
P. Sakthivel ◽  
K. Sethusankar ◽  
P. Jai Sankar ◽  
P. S. Joseph
Keyword(s):  
Molecular Structure ◽  
Hydrogen Bonds ◽  
Dihedral Angle ◽  
Title Compound ◽  
Phenyl Ring ◽  
Compound C ◽  
The Mean

The phenyl ring in the title compound, C15H11Br2NO2S, makes a dihedral angle of 81.8 (1)° with the mean plane of the indole system. The molecular structure is stabilized by C—H...O hydrogen bonds.

Crystal and molecular structure of B,B-bis(p-tolyl)boroxazolidine and the orthorhombic form of B,B-diphenylboroxazolidine

1976 ◽  
Vol 54 (20) ◽  
pp. 3130-3141 ◽  
Author(s):  
Steven J. Rettig ◽  
James Trotter
Keyword(s):  
Molecular Structure ◽  
Statistical Analysis ◽  
Hydrogen Bonds ◽  
Crystal And Molecular Structure ◽  
Direct Methods ◽  
Length Variation ◽  
Full Matrix ◽  
Space Group ◽  
Phenyl Rings ◽  
Related Compounds

Crystals of B,B-bis(p-tolyl)boroxazolidine, 1c, are trigonal, a = 25.1028(9), c = 12.4184(7) Å, Z = 18, space group [Formula: see text]. And crystals of B,B-diphenylboroxazolidine, 1a, are orthorhombic, a = 17.6420(4), b = 14.2527(3), c = 10.205(1) Å, Z = 8, space group Pbca. Both structures were solved by direct methods and were refined by full-matrix least-squares procedures to final R values of 0.057 and 0.040 for 2230 and 1828 reflections with I ≥ 3σ(I) respectively. Both molecules have structures similar to related compounds and feature intermolecular N—H … O hydrogen bonds (N … O = 2.982(2) for 1c and 2.896(2) Å for 1a). Bond lengths are: for 1c; O—C, 1.413(3), O—B, 1.478(3), N—C, 1.488(3), N—B, 1.657(3), C(sp3)—C(sp3), 1.501(4), B—C, 1.616(3) and 1.623(3), mean C—C(ar), 1.395, N—H, 0.93(2) and 0.94(2), mean C(sp3)—H, 1.00, and mean C(ar)—H, 1.00 Å; for 1a; O—C, 1.409(2), O—B, 1.476(2), N—C, 1.489(2), N—B, 1.655(2), C(sp3)—C(sp3), 1.507(3), B—C, 1.613(2) and 1.620(2), mean C—C(ar), 1.391, N—H, 0.93(2) and 0.92(2), mean C(sp3)—H, 1.00, and mean C(ar)—H, 0.98 Å. A statistical analysis of the phenyl C—C distances in compounds 1a, 1b, and 1c has provided an example of statistically significant substituent-induced bond length variation in the phenyl rings.

scholarly journals (Z)-3-(1-Chloroprop-1-enyl)-2-methyl-1-phenylsulfonyl-1H-indole

2013 ◽  
Vol 69 (12) ◽  
pp. o1781-o1781 ◽  
Author(s):  
M. Umadevi ◽  
V. Saravanan ◽  
R. Yamuna ◽  
A. K. Mohanakrishnan ◽  
G. Chakkaravarthi
Keyword(s):  
Molecular Structure ◽  
Hydrogen Bond ◽  
Hydrogen Bonds ◽  
Phenyl Ring ◽  
Three Dimensional ◽  
Ring System ◽  
Indole Ring ◽  
Compound C ◽  
Dimensional Network ◽  
A Chain

In the title compound, C18H16ClNO2S, the indole ring system forms a dihedral angle of 75.07 (8)° with the phenyl ring. The molecular structure is stabilized by a weak intramolecular C—H...O hydrogen bond. In the crystal, molecules are linked by weak C—H...O hydrogen bonds, forming a chain along [10-1]. C—H...π interactions are also observed, leading to a three-dimensional network.

scholarly journals Crystal structures of three indole derivatives: 3-ethnyl-2-methyl-1-phenylsulfonyl-1H-indole, 4-phenylsulfonyl-3H,4H-cyclopenta[b]indol-1(2H)-one and 1-{2-[(E)-2-(5-chloro-2-nitrophenyl)ethenyl]-1-phenylsulfonyl-1H-indol-3-yl}ethan-1-one chloroform monosolvate

2015 ◽  
Vol 71 (9) ◽  
pp. 1036-1041
Author(s):  
S. Gopinath ◽  
K. Sethusankar ◽  
Bose Muthu Ramalingam ◽  
Arasambattu K. Mohanakrishnan
Keyword(s):  
Molecular Structure ◽  
Hydrogen Bonds ◽  
Crystal Structures ◽  
Dihedral Angles ◽  
Indole Derivatives ◽  
Indole Ring ◽  
Asymmetric Unit ◽  
Ring Systems ◽  
Benzene Rings ◽  
Independent Molecules

The title compounds, C17H13NO2S, (I), C17H13NO3S, (II), and C24H17ClN2O5S·CHCl3, (III), are indole derivatives. Compounds (I) and (II) crystalize with two independent molecules in the asymmetric unit. The indole ring systems in all three structures deviate only slightly from planarity, with dihedral angles between the planes of the pyrrole and benzene rings spanning the tight range 0.20 (9)–1.65 (9)°. These indole ring systems, in turn, are almost orthogonal to the phenylsulfonyl rings [range of dihedral angles between mean planes = 77.21 (8)–89.26 (8)°]. In the three compounds, the molecular structure is stabilized by intramolecular C—H...O hydrogen bonds, generatingS(6) ring motifs with the sulfone O atom. In compounds (I) and (II), the two independent molecules are linked by C—H...O hydrogen bonds and C—H...π interactions, while in compound (III), the molecules are linked by C—H...O hydrogen bonds, generatingR22(22) inversion dimers.

scholarly journals Bis(4,6-di-tert-butyl-2-{N-[4-(diethylamino)phenyl]carboximidoyl}phenolato)cobalt(II)

IUCrData ◽  
2017 ◽  
Vol 2 (6) ◽  
Author(s):  
C.Vidya Rani ◽  
L. Mitu ◽  
G. Chakkaravarthi ◽  
G. Rajagopal
Keyword(s):  
Molecular Structure ◽  
Hydrogen Bonds ◽  
Crystal Packing ◽  
Title Complex ◽  
Dihedral Angles ◽  
Minor Components ◽  
Tetrahedral Geometry ◽  
Acta Cryst ◽  
Distorted Tetrahedral Geometry ◽  
Benzene Rings

In the title complex, [Co(C25H35N2O)2], the cobalt(II) atom has a distorted tetrahedral geometry provided by pairs of O and N atoms. The dihedral angles between the benzene rings of the same ligand are 52.39 (9) and 34.96 (9)°. The molecular structure is stabilized by weak intramolecular C—H...O hydrogen bonds. The crystal packing is stabilized mainly by van der Waals forces. The structure contains a solvent-accessible void of 276 Å3which was treated using the SQUEEZE routine fromPLATON[Spek (2015).Acta Cryst.C71, 9–18]. The methyl C atoms of thetert-butyl groups are rotationally disordered, with site occupancies of 0.802 (3) and 0.548 (9) for the major components and 0.198 (3) and 0.452 (9) for the minor components.

scholarly journals Study on the unsaturated hydrogen bond behavior of bio-based polyamide 56

e-Polymers ◽  
2019 ◽  
Vol 19 (1) ◽  
pp. 23-31
Author(s):  
Shouyun Zhang ◽  
Jinghong Ma
Keyword(s):  
Hydrogen Bond ◽  
Infrared Spectroscopy ◽  
Hydrogen Bonds ◽  
Metal Oxides ◽  
Significant Influence ◽  
Polymer Chains ◽  
Experimental Results ◽  
Bond Behavior ◽  
Unit Structure

AbstractIn this paper, the unsaturated hydrogen bonds (H-bonds) of the bio-based polyamide 56 (PA56) with an odd-even unit structure were analyzed by infrared spectroscopy. It was proved that the bio-based PA56 had less saturated H-bonds, which became attenuated and blue-shifted at the temperature exceeding 260°C. Besides, as H-bond was decayed and broken, new unsaturated H-bonds readily formed. Moreover, the experimental results obtained strongly indicate that the unsaturated H-bonds of bio-based polyamide 56 could react with polar metal oxides. Besides, the intercalation of montmorillonite was found to have a significant influence on the hydrogen bond between polymer chains.

scholarly journals 2-(4,5-Dimethoxy-2-nitrophenyl)-4-methoxy-9-phenylsulfonyl-9H-carbazole-3-carbaldehyde

2014 ◽  
Vol 70 (4) ◽  
pp. o424-o425 ◽  
Author(s):  
P. Narayanan ◽  
K. Sethusankar ◽  
Velu Saravanan ◽  
Arasambattu K. Mohanakrishnan
Keyword(s):  
Molecular Structure ◽  
Hydrogen Bonds ◽  
Dihedral Angle ◽  
Title Compound ◽  
Crystal Packing ◽  
Ring System ◽  
Maximum Deviation ◽  
Π Interactions ◽  
Compound C ◽  
Ring Motif

In the title compound, C28H22N2O8S, the carbazole ring system is roughly planar, with a maximum deviation of 0.084 (3) Å for the C atom connected to the 4,5-dimethoxy-2-nitrophenyl ring. The dihedral angle between the carbazole system and the dimethoxy-substituted nitrophenyl ring is 57.05 (10)°. The aldehyde C atom deviates by 0.164 (5) Å from its attached carbazole ring system. The molecular structure is stabilized by C—H...O interactions which generate twoS(6) and oneS(7) ring motif. In the crystal, molecules are linked by C—H...O hydrogen bonds, formingR33(15) ring motifs, which are further crosslinked byR32(19) ring motifs, resulting in (002) layers. The crystal packing also features C—H...π interactions.

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