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Updated: Jun 22, 2026
14:18
A Strategy for Sensitive, Large Scale Quantitative Metabolomics
Published on: May 27, 2014
Concomitant polymorphism and conformational isomerism in 4-acetylresorcinol
Peter G Jones1, Ionel I Mangalagiu
1Institut für Anorganische und Analytische Chemie, Technische Universität Braunschweig, Postfach 3329, 38023 Braunschweig, Germany. p.jones@tu-bs.de
Summary
Researchers investigated two crystalline forms of 1-(2,4-dihydroxyphenyl)ethanone. A new polymorph was discovered, revealing distinct molecular packing and hydrogen bonding in each form.
Area of Science:
- Crystallography
- Solid-state chemistry
- Organic chemistry
Background:
- Polymorphism, the ability of a compound to exist in multiple crystalline forms, influences material properties.
- 1-(2,4-dihydroxyphenyl)ethanone is a compound with potential applications where solid-state structure is critical.
Purpose of the Study:
- To investigate and characterize the crystal structures of known and novel polymorphs of 1-(2,4-dihydroxyphenyl)ethanone.
- To elucidate the intermolecular interactions, specifically hydrogen bonding, that stabilize each crystal form.
Main Methods:
- Single-crystal X-ray diffraction was employed to determine the crystal structures of both polymorphs.
- Low-temperature analysis was performed on the known polymorph.
- Structural comparison of the two identified polymorphs.
Main Results:
- Two polymorphs of 1-(2,4-dihydroxyphenyl)ethanone, designated (I-M) and (I-O), were identified and structurally characterized.
- Polymorph (I-M) exhibits a P2(1)/c space group with molecules forming chains via O-H...O bonds and sheets via C-H...O bonds.
- Polymorph (I-O), a new form in P2(1)2(1)2(1) space group, displays a different hydrogen bonding network, forming chains and offset layers stabilized by O-H...O and C-H...O interactions.
Conclusions:
- The study successfully identified and characterized two distinct polymorphs of 1-(2,4-dihydroxyphenyl)ethanone.
- The molecular packing and hydrogen bonding patterns differ significantly between the two forms, influencing their solid-state structures.
- Understanding these structural differences is crucial for controlling the properties of this compound.
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