Related Experiment Video
Updated: Jan 5, 2026

Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
Published on: February 15, 2016
The crystal structures and Hirshfeld surface analyses of four
M NizamMohideen1, S Syed Abuthahir1, V Viswanathan2
1PG & Research Department of Physics, The New College (Autonomous), University of Madras, Chennai 600 014, Tamil Nadu, India.
Abstract:
The title compounds, 4-(5-acetamido-3-acetyl-2-methyl-2,3-di-hydro-1,3,4-thia-diazol-2-yl)phenyl benzoate, C20H19N3O4S (I), 4-(5-acetamido-3-acetyl-2-methyl-2,3-di-hydro-1,3,4-thia-diazol-2-yl)phenyl isobutyrate 0.25-hydrate, C17H21N3O4S·0.25H2O (II), 4-(5-acetamido-3-acetyl-2-methyl-2,3-di-hydro-1,3,4-thia-diazol-2-yl)phenyl propionate, C16H19N3O4S (III) and 4-(5-acetamido-3-acetyl-2-methyl-2,3-di-hydro-1,3,4-thia-diazol-2-yl)phenyl cinnamate chloro-form hemisolvate, C22H21N3O4S·0.5CHCl3 (IV), all crystallize with two independent mol-ecules (A and B) in the asymmetric unit in the triclinic P space group. Compound II crystallizes as a quaterhydrate, while compound IV crystallizes as a chloro-form hemisolvate. In compounds I, II, III (mol-ecules A and B) and IV (mol-ecule A) the five-membered thia-diazole ring adopts an envelope conformation, with the tetra-substituted C atom as the flap. In mol-ecule B of IV this ring is flat (r.m.s. deviation 0.044 Å). The central benzene ring is in general almost normal to the mean plane of the thia-diazole ring in each mol-ecule, with dihedral angles ranging from 75.8 (1) to 85.5 (2)°. In the crystals of all four compounds, the A and B mol-ecules are linked via strong N-H⋯O hydrogen bonds and generate centrosymmetric four-membered R 4 4(28) ring motifs. There are C-H⋯O hydrogen bonds present in the crystals of all four compounds, and in I and II there are also C-H⋯π inter-actions present. The inter-molecular contacts in the crystals of all four compounds were analysed using Hirshfeld surface analysis and two-dimensional fingerprint plots.
Related Concept Videos
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 unhybridized p...
Crystal Field Theory - Tetrahedral and Square Planar Complexes
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
Prochirality
Ionic Crystal Structures
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...
Crystal Field Theory - Octahedral Complexes
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
UV–Vis Spectroscopy: Woodward–Fieser Rules
![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)
