Pietrzak Mariusz, Buczyńska Joanna, Duus Fritz, Waluk Jacek, Hansen Poul Erik
Institute of Physical Chemistry, Polish Academy of Sciences Kasprzaka 44 01-224 Warsaw Poland
Department of Science and Environment, Roskilde University Denmark.
RSC Adv. 2021 Dec 23;12(2):681-689. doi: 10.1039/d1ra09020h. eCollection 2021 Dec 22.
The photochemistry of a cyclic β-thioxoketone (2-methyl-1-(2-thioxycyclohexyl)propan-1-one (MTPO)) is investigated by NMR, UV, and IR experiments supported by DFT calculations. MTPO exists as a tautomeric mixture of an enol and a thiol form. Irradiation at low temperature led to a - isomerization of the thiol form resulting in a rather unusual enethiol (3). This is followed by a transfer of the isopropyl methine proton onto the carbonyl carbon resulting in yet another enethiol isomer (4). The photoconversion mechanisms without water present are discussed. Photochemical experiments at ambient temperature showed involvement of water in the excited state and resulted in another keto-form (5). The same species was also obtained when the products of the low temperature experiments were kept in the dark at ambient temperature.
通过核磁共振（NMR）、紫外（UV）和红外（IR）实验，并辅以密度泛函理论（DFT）计算，对环状β-硫代酮（2-甲基-1-(2-硫代环己基)丙-1-酮（MTPO））的光化学性质进行了研究。MTPO以烯醇式和硫醇式的互变异构混合物形式存在。低温照射导致硫醇式发生α-异构化，生成一种相当不寻常的烯硫醇（3）。随后，异丙基亚甲基质子转移到羰基碳上，生成另一种烯硫醇异构体（4）。讨论了无水存在时的光转化机制。室温下的光化学实验表明，水参与了激发态过程，并生成了另一种酮式异构体（5）。当低温实验的产物在室温下避光保存时，也得到了相同的物种。
