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Updated: Feb 18, 2026
Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
Published on: February 15, 2016
Crystal structure of 2,4,6-tri-methyl-benzoic anhydride
Michael A Land1, Katherine N Robertson1, Jason A C Clyburne1
1Atlantic Centre for Green Chemistry, Department of Chemistry, Saint Mary's University, 923 Robie Street, Halifax, Nova Scotia, B3H 3C3 Canada.
Abstract:
The title compound, C20H22O3, was formed in the reaction between 2,4,6-tri-methyl-benzoic acid and N,N-diiso-propyl-ethyl-amine in the presence of 1,3-di-chloro-1,3-bis-(di-methyl-amino)-propenium hydrogen dichloride, and was recrystallized from diethyl ether solution. It is the first exclusively alkyl-substituted benzoic anhydride to have been structurally characterized. The asymmetric unit consists of a half mol-ecule, the other half of which is generated by twofold rotation symmetry; the dihedral angle between the symmetry-related aromatic rings is 54.97 (3)°. The geometric parameters of the aromatic ring are typical of those for 2,4,6-tri-methyl-phenyl substituted groups. The C=O and C-O bond lengths are 1.1934 (12) and 1.3958 (11) Å, respectively, and the angle between these three atoms (O=C-O) is 121.24 (9)°. In the crystal, mol-ecules are linked by weak C-H⋯O hydrogen bonds and C-H⋯π inter-actions. The packing features wavy chains that extend parallel to [001].
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