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Published on: April 19, 2019
Photoisomerization of 2,3-diphenylcyclopropane-1-carboxylic acid derivatives
J Sivaguru1, Steffen Jockusch, Nicholas J Turro
1Department of Chemistry, Tulane University, New Orleans, LA 70118, USA.
Abstract:
Contrary to what is known about cis-1,2-diphenylcyclopropane and its derivatives, we find that they have triplet energies of ca. 311 kJ mol(-1), do not undergo intersystem crossing upon direct excitation, undergo the less common adiabatic photoisomerization to the corresponding trans isomers, and show emission from excited 1,3-diradical intermediates.
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