C–halogen···π interactions and their influence on molecular conformation and crystal packing: a database study

2000 ◽  
Vol 3 (2) ◽  
pp. 135-154 ◽  
Author(s):  
M.D Prasanna ◽  
T.N Guru Row
2014 ◽  
Vol 70 (7) ◽  
pp. o766-o767 ◽  
Author(s):  
Fatmah A. M. Al-Omary ◽  
Hazem A. Ghabbour ◽  
Ali A. El-Emam ◽  
C. S. Chidan Kumar ◽  
Hoong-Kun Fun

The title compound, C19H23N3S, is a functionalized triazoline-3-thione derivative. The benzyl ring is almost normal to the planar 1,2,4-triazole ring (r.m.s. deviation = 0.007 Å) with a dihedral angle of 86.90 (7)°. In the crystal, molecules are linked by pairs of N—H...S hydrogen bonds, forming inversion dimers that encloseR22(8) loops. The crystal packing is further stabilized by weak C—H...π interactions that link adjacent dimeric units into supramolecular chains extending along thea-axis direction.


2012 ◽  
Vol 68 (6) ◽  
pp. o1816-o1816
Author(s):  
Ji-Lai Liu ◽  
Ming-Hui Sun ◽  
Jing-Jun Ma

The title compound, C15H14N2O2, was obtained from the reaction of 3-hydroxybenzaldhyde and 4-methylbenzohydrazide in methanol. In the molecule, the benzene rings form a dihedral angle of 2.9 (3)°. In the crystal, N—H...O and O—H...O hydrogen bonds link the molecules into layers parallel to (101). The crystal packing also exhibits π–π interactions between the aromatic rings [centroid–centroid distance = 3.686 (4) Å].


2014 ◽  
Vol 70 (5) ◽  
pp. o621-o621
Author(s):  
Yizhen Li ◽  
Pu Mao ◽  
Yongmei Xiao ◽  
Liangru Yang ◽  
Lingbo Qu

In the title compound, C30H25N3O3, the central imidazole ring forms dihedral angles of 77.34 (6), 12.56 (6) and 87.04 (6)°, respectively, with theo-nitrobenzene ring and the phenyl substituents in the 5- and 4-positions. The molecular conformation is stabilized by weak intramolecular C—H...π interactions. In the crystal, molecules are linked by O—H...N hydrogen bonds, forming chains running parallel to theb-axis direction.


2016 ◽  
Vol 72 (3) ◽  
pp. 198-202
Author(s):  
Carine Duhayon ◽  
Yves Canac ◽  
Laurent Dubrulle ◽  
Carine Maaliki ◽  
Remi Chauvin

Electrostatic interactions between localized integral charges make the stability and structure of highly charged small and rigid organics intriguing. Can σ/π-electron delocalization compensate reduced conformational freedom by lowering the repulsion between identical charges? The crystal structure of the title salt, C14H16N42+·2CF3SO3−, (2), is described and compared with that of the 2,2′′-bis(diphenylphosphanyl) derivative, (4). The conformations of the dications and their interactions with neighbouring trifluoromethanesulfonate anions are first analyzed from the standpoint of formal electrostatic effects. Neither cation exhibits any geometrical strain induced by the intrinsic repulsion between the positive charges. In contrast, the relative orientation of the imidazolium rings [i.e. antifor (2) andsynfor (4)] is controlled by different configurations of the interactions with the closest trifluoromethanesulfonate anions. The long-range arrangement is also found to be specific: beyond the formal electrostatic packing, C—H...O and C—H...F contacts have no definite `hydrogen-bond' character but allow the delineation of layers, which are either pleated or flat in the packing of (2) or (4), respectively.


2003 ◽  
Vol 6 (2) ◽  
pp. 69-77 ◽  
Author(s):  
Ishu Saraogi ◽  
V.G. Vijay ◽  
Soma Das ◽  
K. Sekar ◽  
T.N. Guru Row

2012 ◽  
Vol 68 (6) ◽  
pp. m829-m829
Author(s):  
Lining Yang ◽  
Yanxiang Zhi ◽  
Jiahui Hei ◽  
Yanqing Miao

The asymmetric unit of the title compound, [Mn(C6H6N4)2(H2O)2](C8H4O4), contains one-half each of the centrosymmetric cation and anion. The MnII atom is coordinated by four N atoms [Mn—N = 2.2168 (14) and 2.2407 (14) Å] from two 2,2′-biimidazole ligands and two water molecules [Mn—O = 2.2521 (14) Å] in a distorted octahedral geometry. Intermolecular N—H...O and O—H...O hydrogen bonds consolidate the crystal packing, which also exhibits π–π interactions between five-membered rings, with a centroid–centroid distance of 3.409 (2) Å.


1983 ◽  
Vol 61 (4) ◽  
pp. 737-742 ◽  
Author(s):  
D. F. R. Gilson ◽  
G. Gomez ◽  
I. S. Butler ◽  
P. J. Fitzpatrick

The barriers to cyclopentadienyl ring rotation in the solid phase have been measured by spin-lattice relaxation time methods for the organometallic complexes CpMn(CO)3 (7.24 kJ mol−1), CpRe(CO)3 (7.15 kJ mol−1), and CpV(CO)4 (7.07 kJ mol−1), where Cp = η5-C5H5. Nonbonded atom–atom potential calculations of the barriers in these complexes and in BzCr(CO)3 (Bz = η6-C6H6) show that the molecular conformation of the Mn and Re compounds is determined by crystal packing forces and that concerted ring motions are possible for the cyclopentadienyl complexes, but not for the benzene chromium tricarbonyl.


2017 ◽  
Vol 73 (10) ◽  
pp. 1483-1487
Author(s):  
P. Sivakumar ◽  
S. Israel ◽  
G. Chakkaravarthi

The title salt (I), C6H8N+·C20H17O8−, comprises a 2-methylpyridinium cation and a 2,3-bis(4-methylbenzoyloxy)succinate mono-anion while the salt (II), 2C6H8N+·2C20H17O8−·5H2O, consists of a pair of 4-methylpyridinium cations and 2,3-bis(4-methylbenzoyloxy)succinate mono-anions and five water molecules of solvation in the asymmetric unit. In (I), the dihedral angle between the aromatic rings of the anion is 40.41 (15)°, comparing with 43.0 (3) and 85.7 (2)° in the conformationally dissimilar anion molecules in (II). The pyridine ring of the cation in (I) is inclined at 23.64 (16) and 42.69 (17)° to the two benzene moieties of the anion. In (II), these comparative values are 4.7 (3), 43.5 (3)° and 43.5 (3), 73.1 (3)° for the two associated cation and anion pairs. The crystal packing of (I) is stabilized by inter-ionic N—H...O, O—H...O and C—H...O hydrogen bonds as well as weak C—H...π interactions, linking the ions into infinite chains along [100]. In the crystal packing of (II), the anions and cations are also linked by N—H...O and O—H...O hydrogen bonds involving also the water molecules, giving a two-dimensional network across (001). The crystal structure is also stabilized by weak C—H...O and C—H...π interactions.


2016 ◽  
Vol 72 (10) ◽  
pp. 758-764 ◽  
Author(s):  
Chi Nguyen Thi Thanh ◽  
Thong Pham Van ◽  
Hai Le Thi Hong ◽  
Luc Van Meervelt

Crystallization experiments with the dinuclear chelate ring complex di-μ-chlorido-bis[(η2-2-allyl-4-methoxy-5-{[(propan-2-yloxy)carbonyl]methoxy}phenyl-κC1)platinum(II)], [Pt2(C15H19O4)2Cl2], containing a derivative of the natural compound eugenol as ligand, have been performed. Using five different sets of crystallization conditions resulted in four different complexes which can be further used as starting compounds for the synthesis of Pt complexes with promising anticancer activities. In the case of vapour diffusion with the binary chloroform–diethyl ether or methylene chloride–diethyl ether systems, no change of the molecular structure was observed. Using evaporation from acetonitrile (at room temperature), dimethylformamide (DMF, at 313 K) or dimethyl sulfoxide (DMSO, at 313 K), however, resulted in the displacement of a chloride ligand by the solvent, giving, respectively, the mononuclear complexes (acetonitrile-κN)(η2-2-allyl-4-methoxy-5-{[(propan-2-yloxy)carbonyl]methoxy}phenyl-κC1)chloridoplatinum(II) monohydrate, [Pt(C15H19O4)Cl(CH3CN)]·H2O, (η2-2-allyl-4-methoxy-5-{[(propan-2-yloxy)carbonyl]methoxy}phenyl-κC1)chlorido(dimethylformamide-κO)platinum(II), [Pt(C15H19O4)Cl(C2H7NO)], and (η2-2-allyl-4-methoxy-5-{[(propan-2-yloxy)carbonyl]methoxy}phenyl-κC1)chlorido(dimethyl sulfoxide-κS)platinum(II), determined as the analogue {η2-2-allyl-4-methoxy-5-[(ethoxycarbonyl)methoxy]phenyl-κC1}chlorido(dimethyl sulfoxide-κS)platinum(II), [Pt(C14H17O4)Cl(C2H6OS)]. The crystal structures confirm that acetonitrile interacts with the PtIIatomviaits N atom, while for DMSO, the S atom is the coordinating atom. For the replacement, the longest of the two Pt—Cl bonds is cleaved, leading to acisposition of the solvent ligand with respect to the allyl group. The crystal packing of the complexes is characterized by dimer formationviaC—H...O and C—H...π interactions, but no π–π interactions are observed despite the presence of the aromatic ring.


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