The influence of <i>ortho</i> substituents on the twisting angle of a nitro group with respect to aromatic six-membered carbon rings

Ridder, D. J. A. De; Schenk, H.

doi:10.1107/s0108768194009213

Cited by 12 publications

(7 citation statements)

References 4 publications

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“…Both ortho-nitro groups are twisted from the plane of the aromatic ring with torsion angles O222--N22--C22---C23 -26.5 (4) and O262--N26---C26---C25 -42.0 (4) °. These values are in agreement with the analyses of Walkinshaw (1986) and De Ridder & Schenk (1995). In contrast, apara-nitro group is close to being planar with the aromatic ring [O241--N24---C24---C23 5.0 (5)°].…”

Section: Picrate Ligand In (2)supporting

confidence: 80%

Bond length–bond order relations and calculated geometries for some benzenoid aromatics, including phenanthridine. Structures of 5,6-dimethylphenanthridinium triflate, [N-(6-phenanthridinylmethyl)-aza-18-crown-6-κ⁵ O,O',O'',O''',O''''](picrate-κ²-O,O')potassium, and [N,N'-bis(6-phenanthridinyl-κN-methyl)-7,16-diaza-18-crown-6-κ⁴ O,O',O'',O

Kiralj¹,

Kojić‐Prodić²,

Žinić³

et al. 1996

Acta Crystallogr Sect B

11
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6
0

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The crystal structures of the title compounds are studied in order to investigate the role of novel fluoroionophores in complexation of sodium and potassium. In the potassium complex seven coordination, including the picrate ligand, is encountered. An additional coordination site is via the phenanthridine nitrogen at 3.252 (2)/~ (second coordination). The complex is of C1 symmetry and the aza-18-crown-6 macrocylic ring exhibits a crown-type conformation. The 7,16-diaza-18-crown-6 macrocycle accommodates a six-coordinate sodium with two additional ligands, via nitrogen from phenanthridine units. The complex cation shows a crystallographic twofold symmetry. The macrocycle is not of the crown-type conformation. In both complexes the alkali metals are shifted out of the cavity centres towards a picrate ligand in [N-(6-phenanthridinylmethyl

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Section: Picrate Ligand In (2)supporting
confidence: 80%

Bond length–bond order relations and calculated geometries for some benzenoid aromatics, including phenanthridine. Structures of 5,6-dimethylphenanthridinium triflate, [N-(6-phenanthridinylmethyl)-aza-18-crown-6-κ⁵ O,O',O'',O''',O''''](picrate-κ²-O,O')potassium, and [N,N'-bis(6-phenanthridinyl-κN-methyl)-7,16-diaza-18-crown-6-κ⁴ O,O',O'',O
Kiralj¹,
Kojić‐Prodić²,
Žinić³
et al. 1996
Acta Crystallogr Sect B
11
0
6
0
View full text Add to dashboard Cite

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“…The hydrazone 6 exhibits a nearly planar structure too being only disturbed by the presence of the nitro substituent in the ortho-position of the aromatic ring ( Fig. 4) which is arranged at an angle of 73.6°with respect to the aromatic plane [23]. In this way, the structure differs strongly from the conformation found in the corresponding carboxylic acid [9] which shows a nearly planar structure.…”

Section: Crystal Structures Of the Free Ligandsmentioning
confidence: 97%

“…The six-membered chelate rings are each planar within experimental error and the dihedral angles between the coordination plane and the aromatic rings are almost equal (81.6°). However, the nitro substituents which are arranged at an angle of 14.8 and 33.5°with respect to their aromatic planes [23] document the non-centrosymmetric structure of the molecule. Furthermore, the two pentane-2,4-dione units deviate from planarity and show different conformations.…”

Section: [Ni(l 6 ) 2 ] (10)mentioning
confidence: 99%

3‐(Arylhydrazono)pentane‐2, 4‐diones and their Complexes with Copper(II) and Nickel(II) — Synthesis and Crystal Structures
Marten
¹
,
Seichter
²
,
Weber
³

2005
Zeitschrift anorg allge chemie
48
11
51
0
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A series of new 3-(arylhydrazono)pentane-2,4-diones (1-6) synthesized from pentane-2,4-dione and diazonium salts of respective anilines using the procedure of Japp-Klingemann are described. Complexes with Cu II and Ni II salts are prepared (7-10, respectively). Spectroscopic properties of these compounds have been studied and X-ray crystal structures of selected hydrazones (3, 4, 6) and of the hydrazone complexes (7-10) are reported. The structures of the uncomplexed hydrazones feature an intramolecular N-H···O interaction to yield a six-membered H-bond ring reflecting preference of the hydrazone tautomeric structure. All the complexes are mononuclear 2:1 (L:M) structures of six-membered 869 chelate type involving N 2 O 2 binding sites that are quadratic arranged but differ in the entire coordination environment dependent on the metal and the ligand substitution including distorted octahedral and quadratic pyramidal coordination geometries in the Cu II complexes 7 and 8 or nearly regular square planar coordination geometry in the Ni II complexes 9 and 10, respectively. In the crystal packings, strong and weak H-bond interactions cause supramolecular network structures.

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“…The rotation of an aromatic nitro goup about the C-NO 2 bond is influenced by adjacent substituents. In a study directed at the development of musk odors in aromatic nitro compounds, De Ridder and Schenk examined 1 the data for compounds from the Cambridge Chrystallographic Data Base. They concluded that the out-of-plane rotation angle caused by one or two adjacent groups was affected by the steric hindrance and electronegativity of ortho substituents.…”

mentioning
confidence: 99%

The Influence of para Substituents on the Rotation of Aromatic Nitro Groups
Hanson
¹
,
Hitchcock
²

2004
Journal of Chemical Research
5
1
2
0
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The steric effect of adjacent methyl and methoxyl groups and the electronic effect of para substituents on the rotation of the plane of an aromatic nitro group relative to the plane of the aromatic ring has been investigated by X-ray crystallography. An electron-donating substituent in the para position decreases the rotation whilst an electron-withdrawing substituent increases the rotation of the plane of the nitro group relative to the aromatic ring.

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The influence of ortho substituents on the twisting angle of a nitro group with respect to aromatic six-membered carbon rings

Cited by 12 publications

References 4 publications

3‐(Arylhydrazono)pentane‐2, 4‐diones and their Complexes with Copper(II) and Nickel(II) — Synthesis and Crystal Structures

The Influence of para Substituents on the Rotation of Aromatic Nitro Groups

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