1. Photo-Fries reaction in acetoxyphenyl thiophenes
- Author
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Fausto Ortica, Enrico Benassi, Paola Moretti, Chiara Bertarelli, Paola Galli, and Andrea Bianco
- Subjects
General Chemical Engineering ,Acetoxyphenyl thiophenes ,Kinetics ,General Physics and Astronomy ,Quantum yield ,Infrared spectroscopy ,02 engineering and technology ,DFT calculations ,010402 general chemistry ,Photochemistry ,01 natural sciences ,H-NMR spectroscopy ,Ultraviolet visible spectroscopy ,Phase (matter) ,Molecule ,Isosbestic point ,Chemistry ,General Chemistry ,021001 nanoscience & nanotechnology ,UV–vis spectroscopy ,0104 chemical sciences ,IR spectroscopy ,0210 nano-technology ,Selectivity ,Photo-Fries reaction - Abstract
Two new acetoxyphenyl thiophenes with different conjugation length and undergoing the photo-Fries reaction upon exposure to UV light are presented. These molecules have been characterized in solution by means of different spectroscopic techniques in order to study the evolution and selectivity of the photo-induced reaction. During such a reaction, isosbestic points appear in the UV–vis spectra, indicating a good selectivity of the reaction for both the derivatives. By means of IR measurements, we follow the reaction and determine the kinetics and the quantum yield. The photoproducts are isolated by HPLC and characterized by 1H-NMR whose results confirm the formation of the ortho derivative as the most probable one and we estimate the degree of conversion of the reaction. High-level quantum mechanical calculations both in gas and solvated phase are employed to strongly support the interpretation of the experimental results, and assess the reaction product.
- Published
- 2020