Investigation of organic monoradicals reactivity using surface-enhanced Raman spectroscopy

Surface-enhanced Raman spectroscopy (SERS) and self-assembled monolayer (SAM) approaches were used to investigate the reactions of organic monoradicals with methanol. An attempt was made to generate monoradicals from thiophenols and phenylmethanethiols substituted with bromine, iodine, and nitro groups by irradiation with UV light. Monolayers of radical precursors were deposited on SERS substrates, which were then immersed in methanol and irradiated for 1 and/or 3, 6,12 and 24 h in a UV photochemical reactor. Pre- and postreaction SERS spectra were obtained by using a confocal Raman microscope and compared with the spectra of expected products of the radical reaction with methanol. Our studies have shown that the efficiency of monoradical generation is highly dependent on the chemical structure of the precursor. In addition, it is shown that both the SERS substrate and experimental conditions used strongly influence the obtained results. (C) 2022 The Author(s). Published by Elsevier B.V.

Automated summary

This study investigates the reactions between organic monoradicals and methanol using surface-enhanced Raman spectroscopy (SERS) and self-assembled monolayer (SAM) approaches. Monoradicals are generated from thiophenols and phenylmethanethiols substituted with bromine, iodine, and nitro groups by UV irradiation. The efficiency of monoradical generation is found to be highly dependent on the chemical structure of the precursor, and both the SERS substrate and experimental conditions strongly influence the obtained results.