0000000001305644
AUTHOR
Katarzyna Gajda
Preparation and molecular structures of N′-(2-heteroarylmethylidene)-3-(3-pyridyl)acrylohydrazides
Abstract The crystal and molecular structures of N′-(2-furylmethylidene)-3-(3-pyridyl)acrylohydrazide and N′-(2-thienylmethylidene)-3-(3-pyridyl)acrylohydrazide are reported, and the influence of the type of the heteroatom on the aromaticity of the aromatic rings is discussed. Both molecules are nearly planar. The geometry of the acrylohydrazide arrangement is comparable to that of homologous compounds. Density functional theory (DFT) calculations were performed in order to analyze the changes in the geometry of the studied compounds in the crystalline state and for the isolated molecule. The most significant changes were observed in the values of the N–N and C–N bond lengths. The harmonic …
Dimethyl 4,4′-(diazenediyl)dibenzoate at 100 K
In the asymmetric part of the unit cell of the title compound, C16H14N2O4, there are two chemically equivalent but crystallographic independent half molecules. The geometric centre of each complete molecule lies on a crystallographic inversion centre. Both molecules are almost planar [mean deviations of atoms in the two molecules are 0.032 (2) and 0.044 (2) Å] and their geometries are similar. In the crystal, molecules are arranged in columns along the a axis. There are no intermolecular donor–acceptor distances shorter than 3.4 Å.
N,N-Dicyclohexylnitramine
Molecules of the title compound, C12H22N2O2, are composed of an nitramine group substituted by two cyclohexane rings. The cyclohexane rings have chair conformations, with the exocyclic C—N bonds in axial orientations. In the crystal, C—H...O hydrogen bonds connect the molecules intoC(6) [-101] zigzag chains.
Theoretical Multipolar Atom Model Transfer in Nitro-Derivatives of N-Methylaniline
The nitroanilines are an example of compounds in which the coexistence of electron-rich and electron-deficient substituents, connected through a conjugated π-electronic system, makes their molecular second-order hyperpolarizability and second-harmonic generation efficiency particularly high. This property makes them extremely interesting from the point of view of charge density distribution analysis. The electron density of three isomeric molecules, i.e., N-methyl-2-nitroaniline, N-methyl-3-nitroaniline, and N-methyl-4-nitroaniline, was calculated theoretically through the multipolar atom model transfer. Two types of refinement models, i.e., multipolar atom model (MAM) and independent atom …
π-Electron delocalization in 2-benzoyl-5-phenylpyrazolidin-3-one
Abstract The crystal and molecular structures of 2-benzoyl-5-phenylpyrazolidin-3-one have been characterized by X-ray diffraction along with density functional theory studies. Cinnamic acid chloride was reacted with benzhydrazide, yielding 2-benzoyl-5-phenylpyrazolidin-3-one. This product was formed in the transformation comprising the nucleophilic addition of benzhydrazide to the styryl fragment of the α,β-unsaturated arrangement and subsequent cyclization. The molecule contains two benzene rings and one five-membered heterocyclic ring with an N–N single bond. The five-membered ring is composed of three atoms of sp 3 hybridization and two atoms of sp 2 hybridization, which cause the flatte…
Synthesis and electronic aspects of tetrahydrobenzothienopyrimidine derivatives
Abstract The chemistry of thiophenes, pyrimidines, triazolopyrimidines and benzothiophenes has drawn much attention because of their biological activities. Their interesting properties are connected with their complex π-electron delocalisation effects. Herein the synthesis, crystal and molecular structures at 100 K and DFT calculated structures of three tetrahydrobenzothienopyrimidine derivatives are reported i.e. 4-hydrazino-5,6,7,8-tetrahydro[1]benzothieno[2,3-d]pyrimidine which was a substrate for 2-phenyl-8,9,10,11-tetrahydro[1]benzothieno[3,2-e][1,2,4]triazolo[1,5-c]pyrimidine and 3-methyl-9,10,11,12-tetrahydro-2H-[1]benzothieno[2′,3′:4,5]pyrimido[1,6-b][1,2,4]triazin-2-one. Moreover t…
4-Fluoro-N-methyl-N-nitroaniline
Molecules of the title compound, C7H7FN2O2, are composed of a nitramine group which is twisted with the respect to the aromatic ring, with an N—N—C—C torsion angle of −117.38 (12)°. In the molecule, the N—N bond length [1.3510 (15) Å] indicates some double-bond character, while the angle between the aromatic ring and the nitramine group rules out further delocalization in the molecule. In the crystal, C—H...F hydrogen bonds connect the molecules intoC11(6) chains along theaaxis. C—H...O hydrogen bonds form, which featureR22(12) loops and further connect these chains.
Substituent effects in trans-p,p'-disubstituted azobenzenes: X-ray structures at 100 K and DFT-calculated structures.
The crystal and molecular structures of twopara-substituted azobenzenes with π-electron-donating –NEt2and π-electron-withdrawing –COOEt groups are reported, along with the effects of the substituents on the aromaticity of the benzene ring. The deformation of the aromatic ring around the –NEt2group inN,N,N′,N′-tetraethyl-4,4′-(diazenediyl)dianiline, C20H28N4, (I), may be caused by steric hindrance and the π-electron-donating effects of the amine group. In this structure, one of the amine N atoms demonstrates clearsp2-hybridization and the other is slightly shifted from the plane of the surrounding atoms. The molecule of the second azobenzene, diethyl 4,4′-(diazenediyl)dibenzoate, C18H18N2O4,…
Substituent effects in nitro derivatives of carbazoles investigated by comparison of low-temperature crystallographic studies with density functional theory (DFT) calculations
The crystal structure of 9H-carbazole, C12H9N, (I), has been redetermined at low temperature for use as a reference structure in a comparative study with the structures of 1-nitro-9H-carbazole, C12H8N2O2, (II), and 9-nitrocarbazole, C12H8N2O2, (III). The molecule of (I) has crystallographically imposed mirror symmetry (Z′ = 0.5). All three solid-state structures are slightly nonplanar, the dihedral angles between the planes of the arene and pyrrole rings ranging from 0.40 (7)° in (III) to 1.82 (18)° in (II). Nevertheless, a density functional theory (DFT) study predicts completely planar conformations for the isolated molecules. To estimate the influence of nitro-group substitution on aroma…
X-ray, conformation and electronic structures of 1-nitropyrrolidine
Abstract The chemistry of pyrrolidine compounds has drawn much attention because of their biological activities. The crystal and molecular structure of 1-nitropyrrolidine (C4H8NNO2) at 150K, along with calculated structures (DFT and MP2), are reported herein. In the solid-state, the asymmetric part of the unit cell is composed of one quartermolecule at the position of two perpendicular mirror planes and the five-membered ring is disordered over a mirror plane, revealing the twisted conformation. Both geometries suggest slight sp3 hybridization of the amine nitrogen atom. The non-planar geometry suggests the lack of conjugation of the amine nitrogen lone pair with the nitro group, however th…
Dimethyl 4,4'-(diazenedi-yl)dibenzoate at 100 K.
In the asymmetric part of the unit cell of the title compound, C16H14N2O4, there are two chemically equivalent but crystallographic independent half molecules. The geometric centre of each complete molecule lies on a crystallographic inversion centre. Both molecules are almost planar [mean deviations of atoms in the two molecules are 0.032 (2) and 0.044 (2) Å] and their geometries are similar. In the crystal, molecules are arranged in columns along theaaxis. There are no intermolecular donor–acceptor distances shorter than 3.4 Å.
CCDC 1533753: Experimental Crystal Structure Determination
Related Article: Karolina Jasiak, Agnieszka Kudelko, Katarzyna Gajda, Błażej Dziuk, Bartosz Zarychta, Krzysztof Ejsmont|2018|Z.Naturforsch.,B:Chem.Sci.|73|725|doi:10.1515/znb-2018-0132
CCDC 995332: Experimental Crystal Structure Determination
Related Article: Katarzyna Gajda, Valeriia Astakhina, Krzysztof Ejsmont, Dmytro Kolomeitsev, Sergiy Kovalenko, Bartosz Zarychta|2015|J.Mol.Struct.|1083|137|doi:10.1016/j.molstruc.2014.11.043
CCDC 992622: Experimental Crystal Structure Determination
Related Article: Katarzyna Gajda, Zdzisław Daszkiewicz, Ewelina Kozubek, Krzysztof Ejsmont, Bartosz Zarychta|2014|Cryst.Growth Des.|14|5737|doi:10.1021/cg500984p
CCDC 988567: Experimental Crystal Structure Determination
Related Article: Katarzyna Gajda, Zdzisław Daszkiewicz, Ewelina Kozubek, Krzysztof Ejsmont, Bartosz Zarychta|2014|Cryst.Growth Des.|14|5737|doi:10.1021/cg500984p
CCDC 995360: Experimental Crystal Structure Determination
Related Article: Katarzyna Gajda, Valeriia Astakhina, Krzysztof Ejsmont, Dmytro Kolomeitsev, Sergiy Kovalenko, Bartosz Zarychta|2015|J.Mol.Struct.|1083|137|doi:10.1016/j.molstruc.2014.11.043
CCDC 995342: Experimental Crystal Structure Determination
Related Article: Katarzyna Gajda, Valeriia Astakhina, Krzysztof Ejsmont, Dmytro Kolomeitsev, Sergiy Kovalenko, Bartosz Zarychta|2015|J.Mol.Struct.|1083|137|doi:10.1016/j.molstruc.2014.11.043
CCDC 1409554: Experimental Crystal Structure Determination
Related Article: Katarzyna Gajda, Krzysztof Ejsmont, Zdzisław Daszkiewicz, Christopher G. Gianopoulos, Bartosz Zarychta|2016|J.Mol.Struct.|1108|590|doi:10.1016/j.molstruc.2015.12.050
CCDC 988568: Experimental Crystal Structure Determination
Related Article: Katarzyna Gajda, Zdzisław Daszkiewicz, Ewelina Kozubek, Krzysztof Ejsmont, Bartosz Zarychta|2014|Cryst.Growth Des.|14|5737|doi:10.1021/cg500984p
CCDC 1520500: Experimental Crystal Structure Determination
Related Article: Monika Olesiejuk, Agnieszka Kudelko, Katarzyna Gajda, Błażej Dziuk, Krzysztof Ejsmont|2018|Z.Naturforsch.,B:Chem.Sci.|73|577|doi:10.1515/znb-2018-0072
CCDC 1533752: Experimental Crystal Structure Determination
Related Article: Karolina Jasiak, Agnieszka Kudelko, Katarzyna Gajda, Błażej Dziuk, Bartosz Zarychta, Krzysztof Ejsmont|2018|Z.Naturforsch.,B:Chem.Sci.|73|725|doi:10.1515/znb-2018-0132