Abstract: 3-Methoxythioxanthone was synthesized, and the structure is identified by¹H NMR, ¹³C NMR, IR and HRMS spectra. The UV-Vis absorption spectra of 3-Methoxythioxanthone shows that it absorbs near the purple light (380 nm) in the visible range and is a visible light photosensitizer. 3-Methoxythioxanthone was applied to the Aza-Henry reaction of 2-phenyl-1,2,3,4-Tetrahydroisoquinoline and Nitromethane. Under the irradiation of purple LED, the photosensitizer with a molar fraction of 5% allowed the reaction to be isolated in a yield of 84% within 6 h. According to the experimental results, the mechanism of photocatalytic reaction of AzaHenry was proposed. The photosensitizer could transfer energy to produce singlet oxygen under the illumination, and singlet oxygen promoted the Aza-Henry reaction.

Key words: Visible light, Photosensitizer, Aza-Henry reaction

摘要： 合成了3-甲氧基噻吨酮，并通过核磁共振、红外光谱、高分辨质谱对其结构进行表征。3-甲氧基噻吨酮紫外-可见光谱表明，其在可见光范围内的紫色光(380 nm)附近有吸收，是一种可见光光敏剂。将该光敏剂应用于2-苯基-1,2,3,4-四氢异喹啉和硝基甲烷的Aza-Henry反应中，在紫色LED光照射的条件下，摩尔分数为5%的光敏剂使反应在6 h内产物的分离产率为84%。根据实验结果，提出了光催化的Aza-Henry反应机理，光敏剂在光照条件下进行能量转移产生单线态氧，单线态氧促进Aza-Henry反应的进行。

关键词: 可见光, 光敏剂, Aza-Henry反应