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Fully Autonomous Characterization and Data Collection from Crystals of Biological Macromolecules
Published on: March 22, 2019
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Characteristic conformation of Mosher's amide elucidated using the cambridge structural database
Akio Ichikawa1, Hiroshi Ono2, Yuji Mikata3
1Division of Insect Sciences, National Institute of Agrobiological Sciences, Tsukuba, Ibaraki 305-8634, Japan. ichikawa@affrc.go.jp.
Molecules (Basel, Switzerland)
|July 21, 2015
Summary
Statistical analysis of MTPA amide conformations reveals preferred orientations for trifluoromethyl and amide carbonyl groups. These findings clarify the structural preferences of these chiral derivatizing agents.
Area of Science:
- Organic Chemistry
- Crystallography
- Stereochemistry
Background:
- 3,3,3-trifluoro-2-methoxy-2-phenylpropanamide (MTPA) amides are crucial chiral derivatizing agents.
- Understanding their crystalline conformations is key to their application in enantiomeric analysis.
Purpose of the Study:
- To statistically analyze the conformations of MTPA amides in the Cambridge Structural Database (CSD).
- To elucidate preferred dihedral angles and spatial arrangements of key functional groups.
Main Methods:
- Statistical analysis of crystal structures from the Cambridge Structural Database (CSD).
- Examination of dihedral angles, including those involving trifluoromethyl, amide carbonyl, and phenyl groups.
Main Results:
- A majority (83%) of amide carbonyl and trifluoromethyl groups exhibit dihedral angles between -30° and 0° (average -13°).
- One fluorine atom is typically antiperiplanar to the amide carbonyl group.
- MTPA amides from primary amines favor a Z-form amide moiety, while Mosher-type amides show conformational flexibility.
Conclusions:
- The study clarifies the predominant conformations of MTPA amides in the solid state.
- These conformational insights are valuable for predicting and interpreting stereochemical outcomes in chemical analyses.
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