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Updated: Jun 21, 2026

Chemoselective Preparation of 1-Iodoalkynes, 1,2-Diiodoalkenes, and 1,1,2-Triiodoalkenes Based on the Oxidative Iodination of Terminal Alkynes
Published on: September 12, 2018
Photodissociation of 2-iodoethanol within the A band
V Alvin Shubert1, Maria Rednic, Stephen T Pratt
1Argonne National Laboratory, Argonne, Illinois 60439, USA.
Abstract:
The photodissociation of 2-iodoethanol was studied within the A (sigma* <-- n) absorption band at several wavelengths between 253 and 298 nm, and the velocity distributions and angular distributions of the photofragments were characterized by using velocity-map ion imaging. The two dominant dissociation channels correspond to the production of the 2-hydroxyethyl radical, C2H4OH, and I(2P(3/2)) and I*(2P(1/2)), and in both channels, approximately 50% of the available excess energy is partitioned into translational energy of the fragments. The branching fractions for the I and I* channels at 266 nm were determined by using a combination of (1) the translational energy distributions for the separate I and I* channels determined by two-photon resonant, three-photon ionization, (2) the distributions for the combined I + I* channels determined by single-photon ionization at 118 nm, and (3) the relative photoionization cross sections of I and I* at 118 nm. Evidence was observed for either the secondary decomposition of C2H4OH, the photodissociation of C2H4OH, or the dissociative ionization of the C2H4OH radicals produced in the I channel. These mechanisms are also discussed.
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