Related Experiment Video
Updated: May 4, 2026

Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
N'-[(E)-1-(2-Hy-droxy-phen-yl)ethyl-idene]pyrazine-2-carbohydrazide
Shahid Hameed1, Mushtaq Ahmad2, M Nawaz Tahir3
1Department of Chemistry, Quaid-i-Azam University, Islamabad, Pakistan.
Abstract:
The title compound, C13H12N4O2, crystallized with two independent mol-ecules (A and B) in the asymmetric unit. Mol-ecule B is planar to within 0.044 (3) Å for all non-H atoms, while mol-ecule A is slightly twisted, with a dihedral angle of 6.29 (4)° between the mean planes of the pyrazine-2-carbohydrazide and 1-(2-hy-droxy-phen-yl)ethanone moieties (r.m.s. deviations = 0.0348 and 0.0428 Å, respectively). S(5) and S(6) ring motifs are formed in both mol-ecules due to the presence of intra-molecular O-H⋯N and N-H⋯N hydrogen bonds. In the crystal, mol-ecules A and B are linked by a C-H⋯O hydrogen bond. They stack along the a-axis direction, forming columns with π-π inter-actions involving inversion-related pyrazine and benzene rings [centroid-centroid distances = 3.5489 (13)-3.8513 (16) Å].
Related Concept Videos
Aromatic Hydrocarbon Cations: Structural Overview
Removing one hydrogen from the intervening CH2 group...
Structures of Carboxylic Acid Derivatives
Carboxylic acid derivatives contain an acyl group attached to a heteroatom such as chlorine, oxygen, or nitrogen. The carbonyl carbon and oxygen are both sp2-hybridized with an unhybridized p orbital.
The three sp2 orbitals of the carbonyl carbon form three σ bonds, one each with the carbonyl oxygen, the α carbon, and the heteroatom, whereas the other two sp2 orbitals of the carbonyl oxygen are occupied by the lone pairs. Further, the...
Diazonium Group Substitution: –OH and –H
Hydrolysis of Chlorobenzene to Phenol: Dow Process
Aryldiazonium Salts to Azo Dyes: Diazo Coupling
Five-Membered Heterocyclic Aromatic Compounds: Overview

![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)