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Updated: Jun 12, 2026
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Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles
Published on: August 22, 2018
Ring conformations and intermolecular interactions in two fused dibenzoazocines
Andrés F Yepes1, Ederson Jaimes, Ali Bahsas
1Laboratorio de Síntesis Orgánica, Escuela de Química, Universidad Industrial de Santander, AA 678 Bucaramanga, Colombia.
Summary
This study details the crystal structures of two complex organic compounds, revealing distinct molecular ordering and interactions. Green chemistry principles were applied, ensuring high atom utilization in their synthesis.
Area of Science:
- Organic Chemistry
- Crystallography
- Green Chemistry
Background:
- The study investigates the structural properties of two novel dibenzo[b,f]azocine and benzo[f]naphtho[1,2-b]azocine derivatives.
- Understanding the molecular arrangement and isomerism in complex organic molecules is crucial for predicting their chemical behavior and potential applications.
Purpose of the Study:
- To elucidate the crystal structures of 5-acetyl-2-chloro-8,11-dimethyl-5,6,11,12-tetrahydrodibenzo[b,f]azocine and a specific isomer of 14-acetyl-8,11-dimethyl-7,8,13,14-tetrahydrobenzo[f]naphtho[1,2-b]azocine.
- To analyze the conformational preferences and intermolecular interactions within these crystalline structures.
- To highlight the application of green chemistry in the synthesis of these compounds.
Main Methods:
- Single-crystal X-ray diffraction was employed to determine the three-dimensional structures of the compounds.
- Analysis of crystallographic data to identify isomerism, molecular conformations, and intermolecular forces.
- Characterization of the synthesis process focusing on green conditions and atom utilization.
Main Results:
- Compound (I), 5-acetyl-2-chloro-8,11-dimethyl-5,6,11,12-tetrahydrodibenzo[b,f]azocine, was found to crystallize as a single, fully ordered isomer.
- Compound (II), a derivative of benzo[f]naphtho[1,2-b]azocine, exhibited threefold whole-molecule disorder, involving both configurational and structural isomers.
- Both compounds feature boat-shaped azocine rings with approximate twofold rotational symmetry.
- Compound (I) showed no specific intermolecular interactions, while compound (II) displayed weak intermolecular chains via pi-pi stacking.
Conclusions:
- The study successfully characterized the distinct crystalline behaviors and structural features of the two complex organic molecules.
- The findings provide insights into the conformational flexibility and intermolecular interactions in azocine-containing compounds.
- The synthesis employed green chemistry, demonstrating high atom utilization, aligning with sustainable chemical practices.
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