scholarly journals Crystal structure of 2,4,6-trimethylbenzoic anhydride

2017 ◽  
Vol 73 (11) ◽  
pp. 1735-1738
Author(s):  
Michael A. Land ◽  
Katherine N. Robertson ◽  
Jason A. C. Clyburne

The title compound, C20H22O3, was formed in the reaction between 2,4,6-trimethylbenzoic acid andN,N-diisopropylethylamine in the presence of 1,3-dichloro-1,3-bis(dimethylamino)propenium hydrogen dichloride, and was recrystallized from diethyl ether solution. It is the first exclusively alkyl-substituted benzoic anhydride to have been structurally characterized. The asymmetric unit consists of a half molecule, the other half of which is generated by twofold rotation symmetry; the dihedral angle between the symmetry-related aromatic rings is 54.97 (3)°. The geometric parameters of the aromatic ring are typical of those for 2,4,6-trimethylphenyl substituted groups. The C=O and C—O bond lengths are 1.1934 (12) and 1.3958 (11) Å, respectively, and the angle between these three atoms (O=C—O) is 121.24 (9)°. In the crystal, molecules are linked by weak C—H...O hydrogen bonds and C—H...π interactions. The packing features wavy chains that extend parallel to [001].

Author(s):  
Md. Serajul Haque Faizi ◽  
Turganbay S. Iskenderov ◽  
Natalia O. Sharkina

The title compound, C19H16N2O, crystallized with two independent molecules (AandB) in the asymmetric unit. There is an intramolecular O—H...N hydrogen bond in each molecule with the phenol ring being inclined to the central benzene ring by 4.93 (14) and 7.12 (14)° in moleculesAandB, respectively. The conformation of the two molecules differs essentially in the orientation of the terminal aminophenyl ring with respect to the central benzene ring; this dihedral angle is 50.51 (4)° in moleculeAand 54.61 (14)° in moleculeB. The two outer aromatic rings are inclined to one another by 51.39 (14) and 49.88 (14)° in moleculesAandB, respectively. In the crystal, molecules are connected by N—H...O hydrogen bonds generating –A-B–A–B– zigzag chains extending along [010]. The chains are linkedviaC—H...π interactions involving neighbouringAmolecules, forming slabs lying parallel to (100).


2015 ◽  
Vol 71 (6) ◽  
pp. o425-o425 ◽  
Author(s):  
Farook Adam ◽  
Nadiah Ameram ◽  
Wai Mun Tan

There are two molecules in the asymmetric unit of the title compound, C9H10N2OS. In one, the dihedral angle between the aromatic ring and the carbamothioyl group is 52.31 (7)° and in the other it is 36.16 (6)°. Each molecule features an intramolecular N—H...O hydrogen bond, which generates anS(6) ring and the O and S atoms have anantidisposition. In the crystal, molecules are linked by N—H...S and N—H...O hydrogen bonds, generating separate [130] and [1-30] infinite chains. Weak C—H...O and C—H...S interactions are also observed.


2012 ◽  
Vol 68 (6) ◽  
pp. o1915-o1915
Author(s):  
P. Balamurugan ◽  
K. Kanmani Raja ◽  
I. Mohammed Bilal ◽  
G. Chakkaravarthi ◽  
G. Rajagopal

The asymmetric unit of title compound, C19H22INO, contains two independent molecules. Classical intramolecular O—H...N hydrogen bonds stabilize the molecular structures. The crystal structure is stabilized by weak intermolecular C—H...π and π–π [centroid–centroid = 3.8622 (18) Å] interactions. In both molecules, the aromatic rings are nearly perpendicular to each other [dihedral angles = 84.26 (17) and 86.69 (15)°].


2007 ◽  
Vol 63 (11) ◽  
pp. o4374-o4375 ◽  
Author(s):  
Mustafa Odabaşoğlu ◽  
Orhan Büyükgüngör

The crystal structure of the title compound, C7H7F3N+·C8H3Cl2O4 −, is stabilized by five N—H...O, one O—H...O, two C—H...O and three C—H...X (X = F, Cl) hydrogen bonds. Intramolecular O—H...O and C—H...X hydrogen bonds generate edge-fused [S(7)R 4 4(24)S(7)R 2 2(10)S(7)R 4 4(24)S(7)] motifs. The cations and anions are linked to each other by C—H...O hydrogen bonds, forming a chain along the c axis. This chain and the other hydrogen bonds form [R 3 2(6)R 1 2(4)S(7)R 1 2(4)R 4 4(18)R 5 5(24)R 4 4(18)R 1 2(4)R 1 2(4)S(7)R 1 2(4)R 3 2(6)] motifs. The dihedral angle between the planes of the aromatic rings in the cation and anion is 34.86 (1)°.


2014 ◽  
Vol 70 (9) ◽  
pp. o970-o970 ◽  
Author(s):  
Rosa Carballo ◽  
Arantxa Pino-Cuevas ◽  
Ezequiel M. Vázquez-López

The asymmetric unit of the title compound, C9H9N3OS, contains two approximately planar molecules (r.m.s. deviations for 14 non-H atoms = 0.094 and 0.045 Å), with different conformations. In one of them, the C=O group issynto the S atom and in the other it isanti. Each molecule features an intramolecular N—H...N hydrogen bond, which generates anS(5) ring. In the crystal, molecules are linked by N—H...O and N—H...S hydrogen bonds, generating discrete networks; thesynmolecules form [010] chains and theantimolecules form (100) sheets.


2014 ◽  
Vol 70 (9) ◽  
pp. o917-o918 ◽  
Author(s):  
Błażej Dziuk ◽  
Bartosz Zarychta ◽  
Krzysztof Ejsmont

The asymmetric unit of the title compound, C2H8N+·C4H5O4−, consists of two allylammonium cations and two hydrogen succinate anions (Z′ = 2). One of the cations has a near-perfectsyn-periplanar (cis) conformation with an N—C—C—C torsion angle of 0.4 (3)°, while the other is characterized by agaucheconformation and a torsion angle of 102.5 (3)°. Regarding the anions, three out of four carboxilic groups are twisted with respect to the central C–CH2–CH2–C group [dihedral angles = 24.4 (2), 31.2 (2) and 40.4 (2)°], the remaining one being instead almost coplanar, with a dihedral angle of 4.0 (2)°. In the crystal, there are two very short, near linear O—H...O hydrogen bonds between anions, with the H atoms shifted notably from the donor O towards the O...O midpoint. These O—H...O hydrogen bonds form helical chains along the [011] which are further linked to each other through N—H...O hydrogen bonds (involving all the available NH groups), forming layers lying parallel to (100).


2009 ◽  
Vol 65 (6) ◽  
pp. o1416-o1416 ◽  
Author(s):  
Jian-Cheng Zhou ◽  
Nai-Xu Li ◽  
Chuan-Ming Zhang ◽  
Zheng-Yun Zhang

The asymmetric unit of the title compound, C22H26N2O, contains three crystallographically independent molecules, in which the aromatic rings are oriented at dihedral angles of 21.74 (5), 27.59 (5) and 27.87 (5)°. Intramolecular O—H...N hydrogen bonds result in the formation of planar six-membered rings, and these are nearly coplanar with the adjacent rings. In the crystal structure, π–π contacts between the benzene rings [centroid–centroid distances = 3.989 (2), 3.802 (1) and 3.882 (1) Å] may stabilize the structure.


2012 ◽  
Vol 68 (8) ◽  
pp. o2445-o2446 ◽  
Author(s):  
Aliakbar Dehno Khalaji ◽  
Mahsa Nikookar ◽  
Karla Fejfarová ◽  
Michal Dušek

The crystal structure of the title compound, C14H12N2O4, contains four crystallographically independent molecules in the asymmetric unit. All the molecules have similar conformations; the dihedral angles between the aromatic rings are 33.1 (1), 33.76 (9), 31.41 (9) and 32.56 (10)°. Intramolecular O—H...N hydrogen bonds formS(6) ring motifs in each molecule. In the crystal, there are two pairs of pseudo-inversion-related molecules. Along thecaxis, molecules are stacked with π–π interactions between the 2-hydroxyphenyl and 4-methoxy-2-nitrophenyl rings [centroid–centroid distances = 3.5441 (12)–3.7698 (12) Å].


2015 ◽  
Vol 71 (6) ◽  
pp. o419-o420
Author(s):  
Gamal A. El-Hiti ◽  
Keith Smith ◽  
Amany S. Hegazy ◽  
Saud A. Alanazi ◽  
Benson M. Kariuki

There are two molecules in the asymmetric unit of the title compound, C11H16N2O. The pyridine rings and amide groups overlap almost perfectly (r.m.s. overlay fit = 0.053 Å), but the tertiary butyl groups have different orientations: in one molecule, one of the methyl C atoms issynto the amide O atom [O—C—C—C = −0.8 (3)°] and in the other the equivalent torsion angle is 31.0 (2)°. In the crystal, the two independent molecules are linked by a pair of N—H...N hydrogen bonds in the form of anR22(8) loop to form a dimer. A C—H...O interaction connects the dimers into [100] chains.


2009 ◽  
Vol 65 (6) ◽  
pp. o1294-o1295
Author(s):  
Hoong-Kun Fun ◽  
Samuel Robinson Jebas ◽  
Mehtab Parveen ◽  
Zakia Khanam ◽  
Raza Murad Ghalib

In the crystal structure, the title compound, C24H22O8, lies on a twofold rotation axis and the asymmetric unit comprises one half-molecule. The dihedral angle formed by the coumarin unit with the symmetry-related part is 74.78 (14)°. One of the methoxy groups attached to the coumarin unit is considerably twisted, making an angle of 87.17 (17)° with respect to the coumarin unit; the other is twisted by 0.66 (19)°. No classical hydrogen bonds are found in the sturcture; only a weak C—H...π interaction and short intramolecular O...O contacts [2.683 (2)–2.701 (2) Å] are observed.


Sign in / Sign up

Export Citation Format

Share Document