Mechanistic Study of a Photocatalyzed CS Bond Formation Involving Alkyl/Aryl Thiosulfate
作者:Yiming Li、Weisi Xie、Xuefeng Jiang
DOI:10.1002/chem.201502951
日期:2015.11.2
This study presents thioether construction involving alkyl/aryl thiosulfates and diazonium salt catalyzed by visible‐light‐excited [Ru(bpy)3Cl2] at room temperature in 44–86 % yield. Electron paramagnetic resonance studies found that thiosulfate radical formation was promoted by K2CO3. Conversely, radicals generated from BnSH or BnSSBn (Bn=benzyl) were clearly suppressed, demonstrating the special
这项研究提出了在室温下可见光激发[Ru(bpy)3 Cl 2 ]催化的含烷基/芳基硫代硫酸盐和重氮盐的硫醚结构,产率为44-86%。电子顺磁共振研究发现,K 2 CO 3促进了硫代硫酸根的形成。相反,从BnSH或BnSSBn(Bn =苄基)生成的自由基被明显抑制,证明了该系统中硫代硫酸盐的特殊性质。瞬态吸收光谱证实了[Ru(bpy)3 Cl 2 ]与4-MeO-苯基重氮盐之间的电子转移过程,其速率常数为1.69×10 9 M -1 s -1。通过X射线衍射确认了相应的自由基捕获产物。确定了完整的反应机理以及发射猝灭数据。此外,该系统有效地避免了在含有Ru 2+的光激发体系中H 2 O引起的硫化物过氧化。研究了具有各种电子性质的芳基和杂芳基重氮盐的合成兼容性。烷基和芳基取代的硫代硫酸盐都可用作底物。值得注意的是,药物衍生物在温和的条件下能够平稳地进行后期硫化。
A Highly Efficient Cu-Catalyzed S-Transfer Reaction: From Amine to Sulfide
作者:Yiming Li、Jiahua Pu、Xuefeng Jiang
DOI:10.1021/ol5009747
日期:2014.5.16
A highly efficient Cu-catalyzed dual C-S bonds formation reaction, proceeding in alcohol and water under air, is reported, in which inodorous stable Na2S2O3 is used as a sulfurating reagent. This powerful strategy provides a practical and efficient approach to construct thioethers, using readily available aromatic amines and alkyl halides as starting materials. Sensitive and synthetic useful functional groups could be tolerated. Furthermore, pharmaceuticals, glucose, an amino acid, and a chiral ligand are successfully furnished by this late-stage sulfuration strategy.
Selective Late‐Stage Oxygenation of Sulfides with Ground‐State Oxygen by Uranyl Photocatalysis
late-stage oxygenation of sulfur-containing complex molecules with ground-stateoxygen under ambient conditions. The high oxidation potential of the active uranyl cation (UO2 2+ ) enabled the efficient synthesis of sulfones. The ligand-to-metal charge transfer process (LMCT) from O 2p to U 5f within the O=U=O group, which generates a UV center and an oxygen radical, is assumed to be affected by the solvent
氧合是合成中的基本转变。在这里,我们描述了在环境条件下用基态氧对含硫配合物分子的选择性后期氧合。活性铀酰阳离子(UO2 2+)的高氧化势使砜的有效合成成为可能。假设O = U = O组中从O 2p到U 5f的配体到金属的电荷转移过程(LMCT)会产生UV中心和一个氧自由基,并且受溶剂和添加剂的影响,并且可以调整以促进选择性硫氧化。这种可调策略可以通过后期氧合以原子和步长高效的方式分批合成32种药物和类似物。
Sulfide synthesis through copper-catalyzed C–S bond formation under biomolecule-compatible conditions