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Updated: May 31, 2026
12:07
Microwave-assisted Intramolecular Dehydrogenative Diels-Alder Reactions for the Synthesis of Functionalized Naphthalenes/Solvatochromic Dyes
Published on: April 1, 2013
Zwitterionic (E)-1-[(4-nitro-phen-yl)iminio-meth-yl]naphthalen-2-olate.
Summary
This study synthesized a novel Schiff base compound with a zwitterionic structure. The molecule exhibits intramolecular hydrogen bonding and a nearly planar conformation, with intermolecular interactions forming crystal layers.
Area of Science:
- Organic Chemistry
- Crystallography
- Supramolecular Chemistry
Background:
- Schiff bases are versatile organic compounds with diverse applications.
- Understanding the solid-state structure of Schiff bases is crucial for predicting their properties.
- Zwitterionic compounds exhibit unique electronic and structural characteristics.
Purpose of the Study:
- To synthesize and characterize a novel Schiff base derived from 2-hydroxy-1-naphthaldehyde and 4-nitro-benzenamine.
- To elucidate the crystal structure and intermolecular interactions of the synthesized compound.
- To investigate the tautomeric form and hydrogen bonding in the solid state.
Main Methods:
- Chemical synthesis via condensation reaction.
- Single-crystal X-ray diffraction for structural analysis.
- Analysis of molecular planarity and hydrogen bonding networks.
Main Results:
- Successful synthesis of the target Schiff base, C(17)H(12)N(2)O(3).
- The compound crystallizes in a zwitterionic form, adopting a keto-amino tautomer.
- A short intramolecular N-H⋯O hydrogen bond and electron delocalization were observed.
- The molecule is nearly planar (dihedral angle 1.96°).
- Intermolecular C-H⋯O hydrogen bonds link molecules into layers parallel to the (101) plane.
Conclusions:
- The synthesized Schiff base possesses a unique zwitterionic structure with significant intramolecular hydrogen bonding.
- The nearly planar molecular geometry and observed intermolecular interactions dictate the crystal packing.
- This study provides insights into the structural features of naphthaldehyde-based Schiff bases.
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