Double-twist Möbius Aromaticity in a 4n+2 Electron Electrocyclic Reaction

Henry S. Rzepa

Department of Chemistry, Imperial College London, South Kensington Campus, Exhibition Road, London, SW7 2AY

Electronic Supporting Information

The models below use the Jmol Java-based applet for visualisation of molecular geometries and animations. To ensure this runs correctly, please install Java JRE Version 1.4.2_5 or higher on your computer, and ensure that the local security policy enables applet display. The coordinates for each computed stationary point are in CML (Chemical Markup Language), MDL Molfile or XYZ animation form.

Table S1. Calculated (B3LYP/6-31G(d) ) Geometries and transition normal modes for the electrocyclic ring openings 1-4.
1, R=H 2, R=H
3, R=H 4, R=H
Double-twist Mobius cyclacene band7 Triple-twist Mobius cyclacene band7
1, R=tBu 4, R=tBu
4, R=tBu, Reactant 4, R=tBu, Product
4, R=(R,R)-CHFCl 4, R=(S,S)-CHFCl

Molecular orbitals

To demonstrate the 3D nature of the orbitals, each thumbnail image is linked to a 3DMF file. To view these orbital models, you will need a 3DMF viewer such as 3DMFPlugin (a browser plugin), 3DMF Optimizer or Geo3D (Macintosh applications) or 3DMF Viewer for Windows. To install a Browser plugin for use under Windows;

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  2. Download this plugin
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Table S2. Calculated five highest energy molecular orbitals for 3 at the B3LYP/6-31G(d) level, contoured at 0.01 au.
double-mobius orbital double-mobius orbital
double-mobius orbital double-mobius orbital
double-mobius orbital


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