Related Experiment Video
Updated: Jun 5, 2026

08:12
A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species
Published on: August 16, 2018
2-Phenyl-imidazo[1,2-a]pyridine-3-carbaldehyde.
Acta Crystallographica. Section E, Structure Reports Online
|January 5, 2011
Summary
This study details the crystal structure of a novel organic compound, revealing a specific dihedral angle between its fused ring systems. Molecular chains are formed via hydrogen bonds and further linked by pi-pi stacking interactions.
Area of Science:
- Crystallography
- Organic Chemistry
- Supramolecular Chemistry
Background:
- Understanding the three-dimensional arrangement of molecules is crucial for predicting material properties.
- Imidazo[1,2-a]pyridine derivatives are known for their diverse biological and photophysical applications.
Purpose of the Study:
- To elucidate the crystal structure and intermolecular interactions of a specific imidazo[1,2-a]pyridine derivative.
- To characterize the packing arrangement and bonding in the solid state.
Main Methods:
- Single-crystal X-ray diffraction analysis was employed to determine the molecular and crystal structure.
- Analysis of hydrogen bonding and pi-pi stacking interactions was performed.
Main Results:
- The crystal structure of C(14)H(10)N(2)O was determined, showing a dihedral angle of 28.61° between the imidazo[1,2-a]pyridine and phenyl rings.
- Molecules form extended chains along the a-axis through C-H⋯O and C-H⋯N hydrogen bonds.
- Inter-ribbon linkage occurs via π-π stacking between pyridine rings with a centroid-centroid distance of 3.7187 Å.
Conclusions:
- The study provides detailed insights into the solid-state structure and supramolecular assembly of the title compound.
- The identified hydrogen bonding and π-π stacking interactions are key factors governing the crystal packing.
Related Concept Videos
Aryldiazonium Salts to Azo Dyes: Diazo Coupling
The reaction of weakly electrophilic aryldiazonium (also called arenediazonium) salts with highly activated aromatic compounds leads to the formation of products with an —N=N— link, called an azo linkage. This reaction, presented in Figure 1, is known as diazo coupling and occurs without the loss of the nitrogen atoms of the aryldiazonium salt. Highly activated aromatic compounds such as phenols or arylamines favor the diazo coupling reaction. The coupling generally occurs at the para position.
IUPAC Nomenclature of Aldehydes
Aldehydes are named based on the systematic nomenclature rules set by the IUPAC. For acyclic aldehydes, the longest carbon chain containing the aldehydic (–CHO) group is considered the parent chain. The aldehyde is named by replacing the last letter “e” in the hydrocarbon name with “al”. For instance, a simple, seven-carbon-membered acyclic aldehyde is called heptanal, derived from heptane. The carbon chain is numbered starting from the aldehydic carbon, although the aldehydic carbon’s locant...
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).
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...
Removing one hydrogen from the intervening CH2 group with both...
Benzene to Phenol via Cumene: Hock Process
The synthesis of phenol from benzene via cumene and cumene hydroperoxide is called the Hock process. First, a Friedel–Crafts alkylation reaction of benzene with propene gives cumene. Then cumene forms cumene hydroperoxide via a radical chain reaction. In the chain initiation step, the benzylic hydrogen is abstracted to give a benzylic radical. In the chain propagation step, the benzylic radical reacts with an oxygen diradical to form a cumene hydroperoxide radical. The cumene hydroperoxide...
Carbocations
Carbocations are one of the reaction intermediates formed during several nucleophilic substitutions or elimination reactions. A carbocation is an electron-deficient species with the central carbon atom having six electrons and three bonded atoms. The central carbon in a carbocation is sp2 hybridized with trigonal planar geometry. It has an empty p orbital perpendicular to the plane of the structure that can accept electrons. Thus, carbocations act as strong electrophiles and may react with any...

![Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F60786.jpg&w=3840&q=50)