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Updated: Jun 1, 2026
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Metal-free Synthesis of Ynones from Acyl Chlorides and Potassium Alkynyltrifluoroborate Salts
Published on: February 24, 2015
Mesit-yl(2,4,6-trimeth-oxy-phen-yl)borinic acid
Sergiusz Luliński1, Janusz Serwatowski
1Physical Chemistry Department, Faculty of Chemistry, Warsaw University of Technology, Noakowskiego 3, 00-664 Warsaw, Poland.
Summary
This study details the molecular structure of C(18)H(23)BO(4), revealing specific dihedral angles and intramolecular hydrogen bonding. Crystal analysis shows intermolecular interactions forming a 3D network.
Area of Science:
- Crystallography
- Organic Chemistry
- Supramolecular Chemistry
Background:
- Understanding molecular geometry and intermolecular interactions is crucial in crystal engineering.
- Borinic acids and their derivatives exhibit diverse structural motifs and reactivity.
- Aromatic systems with electron-donating groups influence molecular conformation and intermolecular forces.
Purpose of the Study:
- To elucidate the detailed molecular structure of the title compound C(18)H(23)BO(4).
- To investigate the conformational preferences of the aromatic rings and substituent groups.
- To characterize the intra- and intermolecular interactions governing crystal packing.
Main Methods:
- Single-crystal X-ray diffraction analysis was employed to determine the molecular and crystal structure.
- Geometric parameters, including dihedral angles and atomic deviations from planes, were precisely measured.
- Analysis of non-covalent interactions, such as hydrogen bonds and C-H···O/π contacts, was performed.
Main Results:
- The dihedral angle between the aromatic ring planes is 84.88(3)°.
- The borinic acid group (BOH) exhibits a twist of 19.5° relative to the trimethoxyphenyl ring.
- An intramolecular O-H⋯O hydrogen bond and weak C-H⋯O/π interactions stabilize the molecular and crystal structure, forming a 3D network.
Conclusions:
- The molecular structure is characterized by significant non-planarity between aromatic rings and specific conformational arrangements of functional groups.
- Intramolecular hydrogen bonding plays a key role in stabilizing the borinic acid moiety.
- Weak intermolecular interactions dictate the three-dimensional crystal packing, highlighting principles of crystal engineering.
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