13-methyl-2,6-dithia[7]metacyclophane: a useful molecule to connect VT NMR results and structure with calculations.
Ground state energies (DFT) and 1H and 13C NMR chemical shifts are calculated for the conformers of 13-methyl-2,6-dithia[7]metacyclophane (1), and the results are compared with X-ray structural data and variable-temperature NMR data, including the determination of the activation barrier. Calculations predict the correct low energy conformer with good agreement with chemical shifts, bond distances, and angles. VT NMR data for the 10-tert-butyl-substituted derivative 2 indicate that it undergoes the same conformational equilibria as 1. This paper should enhance the confidence that organic chemists have in calculations to satisfactorily predict conformer energies.
Mitchell
Reginald H
RH
Department of Chemistry, University of Victoria, P.O. Box 3065, Victoria, BC, Canada V8W 3V6. regmitch@uvic.ca
Blunden
Rachel
R
Hollett
Gavin
G
Bandyopadhyay
Subhajit
S
Williams
Richard Vaughan
RV
Twamley
Brendan
B