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Updated: Jul 17, 2026

Determination of the Photoisomerization Quantum Yield of a Hydrazone Photoswitch
Published on: February 7, 2022
Conformational and configurational dynamics of a highly fluorinated hydrazone
Sudharsanam Ramanathan1, David M Lemal
1Department of Chemistry, Dartmouth College, Hanover, NH 03755, USA.
Abstract:
The relative populations of two rotamers in the hydrazone of 2H-perfluoro-2-methyl-3-pentanone can be altered from one extreme to the other by increasing the Lewis basicity of the solvent, and the equilibrium E/Z ratio grows correspondingly. Both trends reflect an increase in the effective size of the amino group as a result of hydrogen bonding. The rate of E/Z interconversion is insensitive to the choice of solvent, consistent with the conclusion that the isomerization occurs via N-inversion and not C=N bond rotation.
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