Related Experiment Video
Updated: Jun 17, 2025

Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions
Published on: July 30, 2017
Crystal and mol-ecular structure of 2-methyl-1,4-phenyl-ene bis-(3,5-di-bromo-benzoate)
Nathan J Weeks1, Moira K Lauer1, Gary J Balaich1
1Department of Chemistry & Chemistry Research Center, USAF Academy, Colorado Springs, CO 80840, USA.
Abstract:
The aryl diester compound, 2-methyl-1,4-phenyl-ene bis-(3,5-di-bromo-benzoate), C21H12Br4O4, was synthesized by esterification of methyl hydro-quinone with 3,5-di-bromo-benzoic acid. A crystalline sample was obtained by cooling a sample of the melt (m.p. = 502 K/DSC) to room temperature. The mol-ecular structure consists of a central benzene ring with anti-3,5-di-bromo-benzoate groups symmetrically attached at the 1 and 4 positions and a methyl group attached at the 2 position of the central ring. In the crystal structure (space group P), mol-ecules of the title aryl diester are located on inversion centers imposing disorder of the methyl group and H atom across the central benzene ring. The crystal structure is consolidated by a network of C-H⋯Br hydrogen bonds in addition to weaker and offset π-π inter-actions involving the central benzene rings as well as the rings of the attached 3,5-di-bromo-benzoate groups.
Related Concept Videos
Structure of Benzene: Molecular Orbital Model
Structure of Benzene: Kekulé Model
He proposed that benzene has a cyclic structure of six carbon atoms attached to one hydrogen atom each, with three alternating pi bonds.
VSEPR Theory and the Effect of Lone Pairs
VSEPR Theory and the Basic Shapes
NMR Spectroscopy of Benzene Derivatives
Nomenclature of Aromatic Compounds with Multiple Substituents
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...

