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Updated: May 27, 2026
07:50
Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides
Published on: May 26, 2019
Bis(4-methyl-morpholin-4-ium) tetra-bromidozincate(II).
Acta Crystallographica. Section E, Structure Reports Online
|November 18, 2011
Summary
Researchers synthesized a novel zinc bromide compound using a hydrothermal method. The structure features a unique trimer arrangement stabilized by bifurcated hydrogen bonds between the cation and anion.
Area of Science:
- Inorganic Chemistry
- Crystal Engineering
- Materials Science
Background:
- Metal halide complexes are crucial in catalysis and materials science.
- Understanding supramolecular structures informs the design of new functional materials.
- Morpholine derivatives offer versatile coordination and hydrogen bonding capabilities.
Purpose of the Study:
- To synthesize and characterize a new zinc bromide complex with a morpholine-based cation.
- To investigate the crystal structure and supramolecular assembly of the title compound.
- To explore the role of hydrogen bonding in the formation of the observed crystal lattice.
Main Methods:
- Hydrothermal synthesis utilizing zinc bromide (ZnBr2) and 4-methyl-morpholine.
- Single-crystal X-ray diffraction for structural determination.
- Analysis of bond distances, angles, and intermolecular interactions (hydrogen bonding).
Main Results:
- Successful synthesis of the compound (C(5)H(12)NO)2[ZnBr4].
- The crystal structure reveals two independent cations with chair conformations and a slightly distorted tetrahedral [ZnBr4]2- anion.
- Zn-Br bond lengths range from 2.3996(9) to 2.4247(9) Å.
- Amine hydrogen atoms participate in bifurcated intermolecular N-H⋯Br hydrogen bonds, forming a trimer unit.
Conclusions:
- The hydrothermal method is effective for synthesizing novel metal-organic complexes.
- The compound exhibits a well-defined crystal structure driven by specific cation-anion interactions.
- Bifurcated hydrogen bonding plays a key role in the supramolecular architecture, leading to the formation of a trimer.
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