中科院理化技术研究所吴骊珠团队研究出提出利用量子点和可见光进行烯丙基C（sp3）–H和乙烯基C（sp2）–H的直接硫氢化反应。 相关研究成果于2021年3月04日发表于国际一流学术期刊《德国应用化学》。

直接烯丙基C–H硫基化直接用于烯丙基C（sp 3）–S键的形成。然而，硫醇与过渡金属催化剂之间的强相互作用导致了催化循环的失活或硫原子在氧化条件下的氧化。因此，直接烯丙基（sp3）-H硫基化已被证明是困难的。

在可见光照射下烯丙基（sp3）-H和硫醇S-H的直接、高效、原子和分步经济的硫醇化反应是一个例外。通过自由基捕获实验和电子顺磁共振（EPR）光谱分析，确定了光催化剂量子点表面生成的烯丙基自由基和噻吩基。C–S键的形成不需要外部氧化剂和自由基引发剂，氢（H 2）是副产品。当用乙烯基C（sp2）-H取代烯丙基C（sp3）-H键时，C（sp2）-H和S-H的交叉偶联是通过释放H2实现的。这种独特的转变为有价值的有机硫化学的直接C–H和S–H偶联打开了一扇门。

附：英文原文

Title: Direct Allylic C(sp3)–H and Vinylic C(sp2)–H Thiolation with Hydrogen Evolution by Quantum Dots and Visible Light

Author: Li-Zhu Wu, Cheng Huang, Rui-Nan Ci, Jia Qiao, Xu-Zhe Wang, Bin Chen, Chen-Ho Tung, Ke Feng

Issue&Volume: 04 March 2021

Abstract: Direct allylic C–H thiolation is straightforward for allylic C(sp  3  )–S bond formation. However, strong interactions between thiol and transition metal catalysts lead to deactivation of the catalytic cycle or oxidation of sulfur atom under oxidative condition. Thus, direct allylic C(sp  3  )–H thiolation has proved difficult. Represented herein is an exceptional for direct, efficient, atom‐ and step‐economic thiolation of allylic C(sp  3  )–H and thiol S–H under visible light irradiation. Radical trapping experiments and electron paramagnetic resonance (EPR) spectroscopy identified the allylic radical and thiyl radical generated on the surface of photocatalyst QDs. The C–S bond formation does not require external oxidants and radical initiators, and hydrogen (H  2  ) is produced as byproduct. When vinylic C(sp  2  )–H was used instead of allylic C(sp  3  )–H bond, the cross‐coupling of C(sp  2  )–H and S–H was achieved with liberation of H  2  . Such a unique transformation opens up a door toward direct C–H and S–H coupling for valuable organosulfur chemistry.

DOI: 10.1002/anie.202101947

Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202101947