Ultrafast Photogeneration of a Tetrazolinyl Radical.
Radicals in solution are crucial for many chemical processes. In this work, we unveil the photoreaction sequence leading to radical formation from tetrazolium salts, which are extensively used in enzyme assays and also exhibit a rich photochemistry. Upon UV irradiation, the tetrazolium ion turns into the tetrazolinyl radical via two intermediates on a nanosecond timescale. The solvent's polarity governs the rate of formation, but the reaction pathway towards the tetrazolinyl radical is identical for aqueous and alcoholic solutions, although the final photoproduct distribution differs. These observations provide new insight into the versatile reactivity of tetrazolium salts and ultrafast radical formation in the liquid phase.
Institut für Physikalische und Theoretische Chemie, Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.
Florian
F
Kanal
Institut für Physikalische und Theoretische Chemie, Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.
Domenik
D
Schleier
Physikalische Chemie II, Ruhr-Universität Bochum, Universitätsstraße 150, 44801, Bochum, Germany. patrick.nuernberger@rub.de.
Patrick
P
Nuernberger
D010777:Photochemistry; D013777:Tetrazoles / Q000737:chemistry*; D014466:Ultraviolet Rays
D013777:Tetrazoles
femtochemistry; radicals; reaction mechanisms; reactive intermediates; tetrazolium assays