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Updated: Jun 27, 2026
09:37
Imine Metathesis by Silica-Supported Catalysts Using the Methodology of Surface Organometallic Chemistry
Published on: October 18, 2019
Extremely narrow SiON angles in siloxy-substituted nitrogen-containing rings: a computational investigation
Thomas Foerster1, Derek A Wann, David W H Rankin
1School of Chemistry, University of Edinburgh, West Mains Road, Edinburgh, UKEH9 3JJ.
Dalton Transactions (Cambridge, England : 2003)
|December 17, 2008
Summary
Quantum chemical calculations reveal that saturated heterocyclic rings significantly influence the silicon-oxygen-nitrogen (SiON) bond angle. Piperidine derivatives exhibit particularly narrow SiON angles, impacting molecular geometry.
Area of Science:
- Computational Chemistry
- Inorganic Chemistry
- Organic Chemistry
Background:
- The SiON angle is a critical parameter in understanding the geometry and properties of siloxy compounds.
- Previous studies have investigated SiON angles in acyclic systems, but the effect of saturated rings remained less understood.
Purpose of the Study:
- To investigate the impact of saturated heterocyclic rings on the SiON bond angle.
- To determine if ring size and specific angles within the ring influence the SiON angle.
Main Methods:
- Quantum chemical calculations were performed on various siloxy derivatives of pyrrolidine and piperidine.
- Further calculations included other heterocyclic rings to explore the role of ring structure.
Main Results:
- Pyrrolidine derivatives showed SiON angles comparable to acyclic analogs.
- Piperidine derivatives exhibited notably narrow SiON angles, with one case below 83 degrees.
- Calculations with the (F(3)C)F(2)SiO- group yielded SiON angles below 80 degrees for several ring sizes.
Conclusions:
- The size of the saturated heterocyclic ring, particularly the CNC angle, is a crucial factor in determining the SiON angle.
- Computational methods can predict very narrow SiON angles in specific heterocyclic siloxy compounds.
![Solid-phase Synthesis of [4.4] Spirocyclic Oximes](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F58508.jpg&w=3840&q=50)
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