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Updated: Jun 5, 2026
11:45
Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles
Published on: August 22, 2018
trans-4-(Tosyl-oxymeth-yl)cyclo-hexane-carboxylic acid
Acta Crystallographica. Section E, Structure Reports Online
|January 5, 2011
Summary
This study details a novel intermediate compound crucial for synthesizing poly(amido-amine) (PAMAM) dendrimers. Structural analysis reveals typical cyclohexane geometry and intermolecular hydrogen bonding in its crystal form.
Area of Science:
- Organic Chemistry
- Materials Science
- Crystallography
Background:
- Poly(amido-amine) (PAMAM) dendrimers are advanced macromolecules with diverse applications.
- Developing novel synthetic routes and intermediates is essential for advancing dendrimer chemistry.
Purpose of the Study:
- To characterize a new intermediate compound, C(15)H(20)O(5)S, for PAMAM dendrimer synthesis.
- To elucidate the structural properties and intermolecular interactions of the intermediate.
Main Methods:
- Single-crystal X-ray diffraction was employed to determine the molecular and crystal structure.
- Analysis of bond lengths, bond angles, and hydrogen bonding patterns.
Main Results:
- The compound C(15)H(20)O(5)S was identified as a key intermediate in PAMAM dendrimer synthesis.
- The cyclohexane ring adopts a chair conformation with standard bond lengths and angles.
- Intermolecular O-H⋯O hydrogen bonds link adjacent molecules in the crystal lattice.
- Disordered methyl group hydrogens were observed.
Conclusions:
- The characterized intermediate possesses suitable structural features for subsequent polymerization steps.
- The crystal structure provides insights into intermolecular forces relevant to material properties.
- This work contributes to the synthetic methodology for novel PAMAM dendrimers.
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