Regioselectivity of Radical Addition of Thiols to 1-Alkenes
作者:Ursula Biermann、Jürgen O. Metzger
DOI:10.1002/ejoc.201701692
日期:2018.2.14
The regioselectivities of the radicaladdition of thiol 1 to 1‐alkenes2 correlate with Taft Es parameters of substituent R of 2 to give clear evidence that it is mainly controlled by the steric effect of substituent R because of an unsymmetrical transition state of the thiyl radicaladdition that is well known for alkyl radicals.
巯基1与1-烯烃2自由基加成的区域选择性与取代基R的2的Taft E s参数相关,以提供明确的证据表明,由于硫醇基的不对称过渡态,它主要受取代基R的空间效应控制烷基自由基众所周知的自由基加成。
Visible light initiated hydrothiolation of alkenes and alkynes over ZnIn<sub>2</sub>S<sub>4</sub>
作者:Yuanyuan Li、Jingyu Cai、Mingming Hao、Zhaohui Li
DOI:10.1039/c9gc00328b
日期:——
reductively quenched by the thiols to generate thiyl radicals, which are added to the alkynes/alkenes to generate alkene/alkyl radicals for the propagation of thiol–ene/thiol–yne coupling reactions. The use of solar light and a semiconductor-based photocatalyst to realize the thiol–ene and thiol–yne coupling reactions in a green solvent (methanol), with only stoichiometric thiols required and applicable
C–S键的构建非常重要。烯烃或炔烃与硫醇的氢硫键化是形成C–S键的一种有吸引力且原子经济的方法。在该手稿中,通过溶剂热法制备了由交织纳米薄片组成的ZnIn 2 S 4花状微球,并将其首次应用于可见光引发的烯烃和炔烃的加氢硫醇化反应。各种硫醇与炔烃或烯烃之间在经过辐照的ZnIn 2 S 4上的反应以中等至极好的收率提供了相应的氢硫醇化产物。根据ESR结果提出的机理表明,在ZnIn 2 S辐照后产生的空穴4被硫醇还原淬灭以生成噻吩基,将其添加到炔烃/烯烃中以生成烯烃/烷基自由基,用于硫醇-烯/硫醇-炔偶联反应的传播。使用太阳光和基于半导体的光催化剂在绿色溶剂(甲醇)中实现硫醇-烯和硫醇-炔偶联反应,仅需要化学计量的硫醇即可,并且适用于广泛的底物范围,使该反应方案成为绿色,可持续且具有成本效益的合成硫醇化产品的策略。这项研究还强调了基于半导体的光催化技术在高级有机合成中的巨大潜力。
Gregg; Alderman; Mayo, Journal of the American Chemical Society, 1948, vol. 70, p. 3741
作者:Gregg、Alderman、Mayo
DOI:——
日期:——
Efficient visible light initiated hydrothiolations of alkenes/alkynes over Ir2S3/ZnIn2S4: Role of Ir2S3
作者:Xinglin Wang、Yuanyuan Li、Zhaohui Li
DOI:10.1016/s1872-2067(20)63660-9
日期:2021.3
The hydrothiolations of alkynes/alkenes with thiols is an atom-economic and thus attractive method for the constructions of C.S bonds. Here Ir2S3/ZnIn2S4 nanocomposites with varied Ir2S3 loadings were obtained by one-pot solvothermal method from ZnCl2, InCl3 and thioacetamide with IrCl3. The loading of Ir2S3 on the surface of ZnIn2S4 promoted the hydrothiolations of alkenes and alkynes, with an optimum performance observed over 0.5 mol% Ir2S3/ZnIn2S4 nanocomposite. Based on the studies on the performance of several other cocatalysts (MoS2, NiS and Pd) loaded ZnIn2S4 and the EIS analyses, it was proposed that the superior performance over Ir2S3/ZnIn2S4 nanocomposite can be ascribed to an improved efficiency on the photogeneration of the thiyl radicals by loading Ir2S3 as well as its inactivity for photocatalytic hydrogen evolution, a side reaction in the light initiated hydrothiolation reaction over ZnIn2S4 . This study not only demonstrates an efficient and green strategy to synthesize thiolated products under visible light based on semiconductor photocatalysis, but also provides some guidances for the design and development of photocatalytic systems for light induced organic syntheses. (C) 2021, Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.
Snyder et al., Journal of the American Chemical Society, 1946, vol. 68, p. 1426