Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Five-Membered Heterocyclic Aromatic Compounds: Overview

Five-Membered Heterocyclic Aromatic Compounds: Overview

Heterocyclic aromatic compounds are cyclic compounds that are aromatic and have one or more heteroatoms—atoms other than carbon, in the ring. Depending upon the number of atoms present in the ring, they can be either five or six-membered. Examples of five-membered heterocyclic aromatic compounds include pyrrole, furan, thiophene, and imidazole. Pyrrole consists of one nitrogen atom having one lone pair of electrons. Furan and thiophene have one oxygen and one sulfur heteroatom, respectively.

Aromatic Hydrocarbon Cations: Structural Overview

Aromatic Hydrocarbon Cations: Structural Overview

Cycloheptatriene is a neutral monocyclic unsaturated hydrocarbon that consists of an odd number of carbon atoms and an intervening sp3 carbon in the ring. The three double bonds in the ring correspond to 6 π electrons, which is a Huckel number, and therefore satisfies the criteria of 4n + 2 π electrons. However, the intervening sp3 carbon disrupts the continuous overlap of p orbitals. As a result, cycloheptatriene is not aromatic.
Removing one hydrogen from the intervening CH2 group with both...

Basicity of Heterocyclic Aromatic Amines

Basicity of Heterocyclic Aromatic Amines

Heterocyclic amines, where the N atom is a part of an alicyclic system, are similar in basicity to alkylamines. Interestingly, the heterocyclic amine having a nitrogen atom as part of an aromatic ring has much less basicity than its corresponding alicyclic counterpart. For this reason, as presented in Figure 1, piperidine (pKb = 2.8) is significantly more basic than pyridine (pKb = 8.8).

Nomenclature of Aromatic Compounds with Multiple Substituents

Nomenclature of Aromatic Compounds with Multiple Substituents

When more than one substituent is present on the benzene ring, the IUPAC nomenclature depends on the number of substituents present.
For disubstituted benzene derivatives, with two groups attached to the benzene ring, three constitutional isomers are possible. For example, consider dimethyl benzene, often called xylene, where the second methyl group can be substituted at the second, third, or fourth carbon. The relative position of the substituents is represented by prefixes ortho, meta, or...

Hybridization of Atomic Orbitals II

Hybridization of Atomic Orbitals II

sp3d and sp3d 2 Hybridization

Structure of Benzene: Molecular Orbital Model

Structure of Benzene: Molecular Orbital Model

According to the molecular orbital (MO) model, benzene has a planar structure with a regular hexagon of six sp2 hybridized carbons. As shown in Figure 1, each carbon is bonded to three other atoms with C–C–C and H–C–C bond angles of 120°. The C–H bond length is 109 pm, and the C–C bond length is 139 pm which is midway between the single bond length of sp3 hybridized carbons (154 pm) and sp2 hybridized carbons (133 pm).

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

Luminescent mesoporous bioactive glass nanoparticles: Samarium-doping for enhanced bone regeneration, antibacterial activity, and bioimaging.

Biomaterials advances·2026

Same author

Modulating Cytotoxicity in HeLa Cells <i>via</i> Aromatic Ring Variation in Cu(I) Complexes.

ACS applied bio materials·2026

Same author

The Multifaceted Benefits of Triphala: Uncovering Phytochemical and Pharmacological Properties From Antiquity to Modern Times.

Chemistry & biodiversity·2025

Same author

Structural insights and <i>in vitro</i> and <i>in vivo</i> anticancer evaluation of dithiocarbamate-based metal complexes against murine lymphoma.

Dalton transactions (Cambridge, England : 2003)·2025

Same author

Embryonic toxicology evaluation of novel <i>Cissus quadrangularis</i>, bioceramics and tendon extracellular matrix incorporated scaffolds for periodontal bone regeneration using zebrafish model.

Journal of oral biology and craniofacial research·2025

Same author

Unraveling the pathogenomics of <i>Rhizoctonia solani</i> infecting proso millet (<i>Panicum miliaceum</i> L.): genomic perspective on ruthless virulence and adaptive evolution.

Frontiers in microbiology·2025

Search research articles

Related Experiment Video

Updated: May 17, 2026

Microwave-Assisted Preparation of 1-Aryl-1H-pyrazole-5-amines

Microwave-Assisted Preparation of 1-Aryl-1H-pyrazole-5-amines

Published on: June 23, 2019

2-Ethyl-3,5,6-triphenyl-pyrazine.

N Anuradha¹, A Thiruvalluvar, S Chitra

¹Postgraduate Research Department of Physics, Rajah Serfoji Government College (Autonomous), Thanjavur 613 005, Tamilnadu, India.

Acta Crystallographica. Section E, Structure Reports Online

|November 6, 2012

Summary

This summary is machine-generated.

This study reveals significant non-planarity in the pyrazine ring of a C24H20N2 molecule, described as a flattened twist-boat conformation. Steric crowding is the likely cause of this distortion in the crystal structure.

More Related Videos

Synthesis of pH Dependent Pyrazole, Imidazole, and Isoindolone Dipyrrinone Fluorophores using a Claisen-Schmidt Condensation Approach

Synthesis of pH Dependent Pyrazole, Imidazole, and Isoindolone Dipyrrinone Fluorophores using a Claisen-Schmidt Condensation Approach

Published on: June 10, 2021

Facile Preparation of (2Z,4E)-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate

Facile Preparation of (2Z,4E)-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate

Published on: June 21, 2017

Related Experiment Videos

Last Updated: May 17, 2026

Microwave-Assisted Preparation of 1-Aryl-1H-pyrazole-5-amines

Microwave-Assisted Preparation of 1-Aryl-1H-pyrazole-5-amines

Published on: June 23, 2019

Synthesis of pH Dependent Pyrazole, Imidazole, and Isoindolone Dipyrrinone Fluorophores using a Claisen-Schmidt Condensation Approach

Synthesis of pH Dependent Pyrazole, Imidazole, and Isoindolone Dipyrrinone Fluorophores using a Claisen-Schmidt Condensation Approach

Published on: June 10, 2021

Facile Preparation of (2Z,4E)-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate

Facile Preparation of (2Z,4E)-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate

Published on: June 21, 2017

Area of Science:

Organic Chemistry
Crystallography

Background:

Molecular structure determination is crucial for understanding chemical properties.
Non-planar conformations can arise from steric hindrance and influence molecular interactions.

Purpose of the Study:

To elucidate the three-dimensional structure of the C24H20N2 molecule.
To investigate the conformational characteristics of the pyrazine and benzene rings.

Main Methods:

Single-crystal X-ray diffraction was employed to analyze the molecular and crystal structure.
Detailed analysis of bond lengths, bond angles, and dihedral angles was performed.

Main Results:

The pyrazine ring exhibits significant deviation from planarity, adopting a flattened twist-boat conformation.
Dihedral angles between adjacent benzene rings and the ethyl-substituted benzene ring were quantified.
The ethyl group displays positional disorder within the crystal lattice.

Conclusions:

Steric crowding is identified as the probable cause for the observed pyrazine ring distortion.
The study provides detailed structural insights into this specific organic molecule.
The absence of intermolecular hydrogen bonds was noted in the crystal packing.