(E)-3-Nitro-N'-(3-nitro-benzyl-idene)-benzohydrazide
1Zibo Vocational Institute, Zibo 255314, People's Republic of China.
Acta Crystallographica. Section E, Structure Reports Online
|March 14, 2012
Summary
Molecular structure analysis reveals a trans conformation in the title compound, C(14)H(10)N(4)O(5). Crystal packing shows molecules forming chains via hydrogen bonds along the c axis.
Area of Science:
- Crystallography
- Molecular Chemistry
Background:
- Understanding molecular conformation and crystal packing is crucial in materials science.
- Hydrogen bonding plays a significant role in supramolecular assembly.
Purpose of the Study:
- To elucidate the molecular structure and crystal packing of the title compound, C(14)H(10)N(4)O(5).
- To investigate the intermolecular interactions present in the crystalline state.
Main Methods:
- Single-crystal X-ray diffraction was employed to determine the three-dimensional structure.
- Analysis of bond lengths, bond angles, and dihedral angles was performed.
- Intermolecular interactions, specifically hydrogen bonding, were identified and analyzed.
Main Results:
- The molecule adopts a trans conformation around the methylidene unit.
- A dihedral angle of 9.8(2)° was measured between the two benzene rings.
- N-H⋯O hydrogen bonds were observed, leading to the formation of molecular chains along the c axis.
Conclusions:
- The study provides detailed structural insights into the title compound.
- The observed hydrogen bonding network dictates the crystal structure and influences material properties.
Related Concept Videos
Electrophilic Aromatic Substitution: Nitration of Benzene
The nitration of benzene is an example of an electrophilic aromatic substitution reaction. It involves the formation of a very powerful electrophile, the nitronium ion, which is linear in shape. The reaction occurs through the interaction of two strong acids, sulfuric and nitric acid.
Diazonium Group Substitution: –OH and –H
Nitrous acid, a weak acid, is prepared in situ via the reaction of sodium nitrite with a strong acid under cold conditions. This nitrous acid prepared in situ reacts with primary arylamines to form arenediazonium salts. Such reactions are known as diazotization reactions. As shown in Figure 1, the formation of arenediazonium salts begins with the decomposition of nitrous acid in an acidic solution to give nitrosonium ions.
1° Amines to Diazonium or Aryldiazonium Salts: Diazotization with NaNO2 Mechanism
Nitrous acid is a relatively weak and unstable acid prepared in situ by the reaction of sodium nitrite and cold, dilute hydrochloric acid. In an acidic solution, the nitrous acid undergoes protonation when it loses water to form a nitrosonium ion—an electrophile. Nitrous acid reacts with primary amines to give diazonium salts. The reaction is called diazotization of primary amines.
Nitrosation of Enols
The nitrosation reaction is one of the methods of preparing 1,2-diketones. The enol tautomer of the starting ketone reacts with sodium nitrite in hydrochloric acid, generating the 1,2-diketone after hydrolysis.
meta-Directing Deactivators: –NO2, –CN, –CHO, –⁠CO2R, –COR, –CO2H
All meta-directing substituents are deactivating groups. These substituents withdraw electrons from the aromatic ring, making the ring less reactive toward electrophilic substitution. For example, the nitration of nitrobenzene is 100,000 times slower than that of benzene because of the deactivating effect of the nitro group. The first step in an electrophilic aromatic substitution is the addition of an electrophile to form a resonance-stabilized carbocation. The energy diagrams for the...
Diazonium Group Substitution with Halogens and Cyanide: Sandmeyer and Schiemann Reactions
Arenediazonium substitution reactions occur when the diazonium group is substituted by various functional groups such as halides, hydroxyl, nitrile, etc. For instance, arenediazonium salts react with copper(I) salts of chloride, bromide, or cyanide to form corresponding aryl chlorides, bromides, and nitriles. These reactions are named Sandmeyer reactions. Although the mechanism of this reaction is complicated, as illustrated in Figure 1, they are believed to progress via an aryl copper...


