Crystal structures of 7-azaindole, an unusual hydrogen-bonded tetramer, and of two of its methylmercury(II) complexes

1990 ◽  
Vol 68 (1) ◽  
pp. 193-201 ◽  
Author(s):  
Pascal Dufour ◽  
Yves Dartiguenave ◽  
Michèle Dartiguenave ◽  
Nathalie Dufour ◽  
Anne-Marie Lebuis ◽  
...  

Crystals of 7-azaindole ([Formula: see text], a = 11.312(4), b = 14.960(6), c = 15.509(5) Å, α = 102.86(3), β = 108.78(3), γ = 90.71(3)°, Z = 16, R = 0.052) contain tetrameric units of approximate S4 symmetry, in which the molecules are associated by means of four complementary N—H … N hydrogen bonds. [CH3Hg(7-azaindole)]NO3 ([Formula: see text], a = 7.818(3), b = 7.884(3), c = 9.135(4) Å, α = 97.89(3), β = 109.13(3), γ = 103.28(3)°, Z = 2, R = 0.039) contains well-separated nitrate ions and complex cations in which the methylmercury group is linearly bonded to the pyridine nitrogen atom, whereas the five-membered ring remains protonated. In the neutral [CH3Hg(azaindolate)] complex ([Formula: see text], a = 10.926(10), b = 11.333(8), c = 11.647(10) Å, α = 92.13(8), β = 104.83(9), γ = 111.86(7)°, Z = 6, R = 0.048), methylmercury groups have substituted the N—H proton in the five-membered ring for the three symmetry-independent molecules. Intermolecular secondary Hg … N bonds are found with pyridine nitrogens. Keywords: azaindole, methylmercury, crystal structure.

2020 ◽  
Vol 76 (9) ◽  
pp. 1503-1507
Author(s):  
Oleksandr S. Vynohradov ◽  
Vadim A. Pavlenko ◽  
Inna S. Safyanova ◽  
Kateryna Znovjyak ◽  
Sergiu Shova ◽  
...  

The title compound, [Cu2(C5H7N2)(C4H10NO2)Cl2(C5H8N2)], is a pyrazolate aminoalcohol complex which contains two dimethylpyrazole molecules in monodentate and bidentate-bridged coordination modes and a monodeprotonated diethanolamine molecule. Both copper atoms are involved in the formation of non-planar five-membered chelate rings. One Cu atom is in a distorted tetrahedral environment formed by the pyridine nitrogen atom of the protonated dimethylpyrazole molecule, the N atom of the deprotonated bridged dimethylpyrazole, the Cl atom and the bridged O atom of the monodeprotonated diethanolamine. The second Cu atom has an intermediate environment between trigonal bipyramidal and square pyramidal, formed by the N atom of the deprotonated bridged dimethylpyrazole, the Cl atom and the N atom of the aminoalcohol, and two O atoms of the deprotonated and protonated OH groups. In the crystal, N—H...Cl hydrogen bonds link the molecules into antisymmetric chains running along the a-axis direction. Adjacent chains are connected by O—H...O hydrogen bonds involving the hydroxyl group as donor.


2002 ◽  
Vol 55 (9) ◽  
pp. 561 ◽  
Author(s):  
W. Li ◽  
S.-L. Zheng ◽  
C.-R. Zhu ◽  
Y.-X. Tong ◽  
X.-M. Chen

The interesting three-dimensional hydrogen-bonded self-assembled network of [(CH2)6N4CH3]+ cations and [CoCl4]2– anions has been prepared and structurally characterized. In the title complex, the quaternization of one hexamethylenetetramine nitrogen atom has been trapped, and further stabilized by the large [CoCl4]2– anions, featuring C–H���Cl hydrogen bonds (3.497–3.709 �) between the methylene groups of [(CH2)6N4CH3]+ cations and the chlorine atoms of the [CoCl4]2– anions.


2014 ◽  
Vol 7 (1) ◽  
pp. 15-19 ◽  
Author(s):  
Danica Čechová ◽  
Alena Martišková ◽  
Jan Moncol

Abstract The crystal structures of the title compounds, [Mn(phen)2Cl2] (I) and [Mn(bipy)2Cl2] (II), have been determined at 150 K. The manganese atoms in both compounds are coordinated by four pyridine nitrogen atoms from two 1,10-phenanthroline or 4,4´-bipyridine ligands and two chloride anions, resulting in a distorted cis-MnN4Cl2 octahedral geometry. Both complexes are connected through C-H・・・Cl hydrogen bonds into frameworks. The π-π stacking interactions are observed in crystal structure of both ones.


2015 ◽  
Vol 71 (10) ◽  
pp. 1117-1120 ◽  
Author(s):  
Dmitrijs Stepanovs ◽  
Daniels Posevins ◽  
Maris Turks

The title compounds consist of a bornane skeleton with attached acetamide, C12H21NO (±)-(1) {systematic name: (±)-N-[(1RS,2RS,4RS)-1,7,7-trimethylbicyclo[2.2.1]heptan-2-yl]acetamide}, and chloroacetamide, C12H20ClNO (±)-(2) {systematic name: (±)-2-chloro-N-[(1RS,2RS,4RS)-1,7,7-trimethylbicyclo[2.2.1]heptan-2-yl]acetamide}, functionalities to the 2-exo-position. The crystal structure of the first monoclinic polymorph of (±)-(1) has been reported previously [Unget al.(2014).Monatsh. Chem.145, 983–992]. Compound (±)-(1) crystallizes in the space groupP21/nwith two independent molecules in the asymmetric unit, in contrast to the above-mentioned polymorph which crystallized in the space groupC2/cwith one molecule in the asymmetric unit. In the title compounds, the bicyclic bornane moieties have normal geometries. In the crystals of both compounds, molecules are linked by N—H...O hydrogen bonds, reinforced by C—H...O contacts, formingtrans-amide chains propagating along thea-axis direction. In the case of compound (±)-(1), neighbouring chains are linked by further C—H...O contacts, forming double-chain ribbons along [100].


2016 ◽  
Vol 72 (10) ◽  
pp. 1429-1433
Author(s):  
Dmitry S. Poplevin ◽  
Fedor I. Zubkov ◽  
Pavel V. Dorovatovskii ◽  
Yan V. Zubavichus ◽  
Victor N. Khrustalev

The isomeric title compounds, C12H13NO4(Ia) and C12H13NO4(IIa), the products of an usual thermal C6-epimerization of 5-oxo-1,2,3,5,5a,6,7,9b-octahydro-7,9a-epoxypyrrolo[2,1-a]isoindole-6-carboxylic acid, represent the two different diastereomers and have very similar molecular geometries. The molecules of both compounds comprise a fused tetracyclic system containing four five-membered rings (pyrrolidine, pyrrolidinone, dihydrofuran and tetrahydrofuran), all of which adopt the usual envelope conformations. The dihedral angle between the basal planes of the pyrrolidine and pyrrolidinone rings are 14.3 (2) and 16.50 (11)°, respectively, for (Ia) and (IIa). The nitrogen atom has a slightly pyramidalized geometry [bond-angle sum = 355.9 and 355.3°, for (Ia) and (IIa)], respectively. In the crystal of (Ia), molecules form zigzag-like hydrogen-bonded chains along [010] through strong O—H...O hydrogen bonds and are further linked by weak C—H...O hydrogen bonds into complex two-tier layers parallel to (100). Unlike (Ia), the crystal of (IIa) contains centrosymmetric cyclic hydrogen-bonded dimers [graph setR22(14)], formed through strong O—H...O hydrogen bonds and are further linked by weak C—H...O hydrogen bonds into ribbons extending across [101].


2017 ◽  
Vol 73 (7) ◽  
pp. 575-581 ◽  
Author(s):  
Philipp Kramer ◽  
Michael Bolte

Kryptoracemates are racemic compounds (pairs of enantiomers) that crystallize in Sohnke space groups (space groups that contain neither inversion centres nor mirror or glide planes nor rotoinversion axes). Thus, the two symmetry-independent molecules cannot be transformed into one another by any symmetry element present in the crystal structure. Usually, the conformation of the two enantiomers is rather similar if not identical. Sometimes, the two enantiomers are related by a pseudosymmetry element, which is often a pseudocentre of inversion, because inversion symmetry is thought to be favourable for crystal packing. We obtained crystals of two kryptoracemates of two very similar compounds differing in just one residue, namely rac-N-[(1S,2R,3S)-2-methyl-3-(5-methylfuran-2-yl)-1-phenyl-3-(pivalamido)propyl]benzamide, C27H32N2O3, (I), and rac-N-[(1S,2S,3R)-2-methyl-3-(5-methylfuran-2-yl)-1-phenyl-3-(propionamido)propyl]benzamide dichloromethane hemisolvate, C25H28N2O3·0.5CH2Cl2, (II). The crystals of both compounds contain both enantiomers of these chiral molecules. However, since the space groups [P212121 for (I) and P1 for (II)] contain neither inversion centres nor mirror or glide planes nor rotoinversion axes, there are both enantiomers in the asymmetric unit, which is a rather uncommon phenomenon. In addition, it is remarkable that (II) contains two pairs of enantiomers in the asymmetric unit. In the crystal, molecules are connected by intermolecular N—H...O hydrogen bonds to form chains or layered structures.


2015 ◽  
Vol 71 (9) ◽  
pp. 1000-1002
Author(s):  
Esra Turan Akın ◽  
Tuncer Hökelek

The asymmetric unit of the title compound, C12H12Cl4O2, contains two crystallographically independent molecules with almost identical conformations (r.m.s. overlay fit for the non-hydrogen atoms = 0.059 Å). In each molecule, the central eight-membered ring has a distorted boat configuration, and two non-planar four-membered rings are fused on either side of the eight-membered ring. A weak C—H...O hydrogen bond links the two independent molecules. In the crystal, weak C—H...O hydrogen bonds link the molecules into a two-dimensional network parallel to (001).


Author(s):  
K. Shakuntala ◽  
S. Naveen ◽  
N. K. Lokanath ◽  
P. A. Suchetan

The crystal structures of three isomeric compounds of formula C14H13Cl2NO2S, namely 3,5-dichloro-N-(2,3-dimethylphenyl)-benzenesulfonamide (I), 3,5-dichloro-N-(2,6-dimethylphenyl)benzenesulfonamide (II) and 3,5-dichloro-N-(3,5-dimethylphenyl)benzenesulfonamide (III) are described. The molecules of all the three compounds are U-shaped with the two aromatic rings inclined at 41.3 (6)° in (I), 42.1 (2)° in (II) and 54.4 (3)° in (III). The molecular conformation of (II) is stabilized by intramolecular C—H...O hydrogen bonds and C—H...π interactions. The crystal structure of (I) features N—H...O hydrogen-bondedR22(8) loops interconnectedvia C(7) chains of C—H...O interactions, forming a three-dimensional architecture. The structure also features π–π interactions [Cg...Cg= 3.6970 (14) Å]. In (II), N—H...O hydrogen-bondedR22(8) loops are interconnectedviaπ–π interactions [intercentroid distance = 3.606 (3) Å] to form a one-dimensional architecture running parallel to theaaxis. In (III), adjacentC(4) chains of N—H...O hydrogen-bonded molecules running parallel to [010] are connectedviaC—H...π interactions, forming sheets parallel to theabplane. Neighbouring sheets are linkedviaoffset π–π interactions [intercentroid distance = 3.8303 (16) Å] to form a three-dimensional architecture.


2006 ◽  
Vol 62 (6) ◽  
pp. 1112-1120 ◽  
Author(s):  
Valerio Bertolasi ◽  
Loretta Pretto ◽  
Valeria Ferretti ◽  
Paola Gilli ◽  
Gastone Gilli

The crystal structures of five β-enaminones are reported: (2Z)-3-(benzylamino)-1,3-diphenyl-prop-2-en-1-one, (2Z)-3-(benzylamino)-3-(2-hydroxyphenyl)-1-phenyl-prop-2-en-1-one, (2Z)-3-(benzylamino)-3-(4-methoxyphenyl)-1-(3-nitrophenyl)-prop-2-en-1-one, 2-{1-[(4-methoxyphenyl)amino]ethylidene}cyclohexene-1,3-dione and 2-{1-[(3-methoxyphenyl)amino]ethylidene}cyclohexene-1,3-dione. The structures were analysed and compared with those of similar compounds in order to establish which factors determine the range (2.53–2.72 Å) of N...O hydrogen-bond distances in intramolecularly hydrogen-bonded β-enaminones. It has been shown that, beyond electronic resonance-assisted hydrogen-bond effects modulated by substituents, the necessary requirements to produce very short N—H...O hydrogen bonding are steric intramolecular repulsions, including the embedding of an enaminonic C—C or C—N bond in an aliphatic six-membered ring. By considering the structural features it is possible to expect the strength of N—H...O hydrogen bonds adopted by specific β-enaminones.


2014 ◽  
Vol 70 (9) ◽  
pp. 912-919
Author(s):  
Quoc Cuong Ton ◽  
Michael Bolte ◽  
Ernst Egert

The crystal structures of eight benzoylhydrazones with different substituents have been investigated, namely 1-benzoyl-2-(propan-2-ylidene)hydrazone, C10H12N2O, (I), 1-benzoyl-2-(1-cyclohexylethylidene)hydrazone, C15H20N2O, (II), 1-benzoyl-2-[1-(naphthalen-2-yl)ethylidene]hydrazone, C19H16N2O, (III), 1-benzoyl-2-(1-cyclohexylbenzylidene)hydrazone, C20H22N2O, (IV), 1-benzoyl-2-(1-phenylbenzylidene)hydrazone, C20H16N2O, (V), 1-benzoyl-2-[1-(4-chlorophenyl)benzylidene]hydrazone, C20H15ClN2O, (VI), 1-benzoyl-2-(4-hydroxybenzylidene)hydrazone methanol monosolvate, C14H12N2O2·CH3OH, (VII), and 1-benzoyl-2-(1,1-diphenylpropan-2-ylidene)hydrazone, C22H20N2O, (VIII). The ten molecules in the eight crystal structures [there are two independent molecules in the structures of (V) and (VI)] show similar conformations and hydrogen-bonding patterns. The C=N—NH—C=O group is planar, but the plane of the phenyl ring of the benzoyl group is rotated by about 30° with respect to that of the keto group [except for (IV), where the groups are coplanar]. Only in the amide group of (VIII) is the N—H groupsynto the C=O bond, whereas the seven other compounds exhibit theanticonformation. Unless prevented by steric hindrance, N—H...O hydrogen bonds help to stabilize the crystal structure, which leads to infinite chains or dimers depending upon the molecular conformation. The molecular packing is supported by intermolecular C—H...O interactions. In the crystal structure of (VII), the methanol solvent molecule participates in two strong hydrogen bonds and two weak C—H...O interactions, thus acting as a link between the molecular chains.


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