The heterogeneous PdCl2/TiO2 efficiently catalyzes the C–C bond formation (Heck reaction) between aryliodides and olefins under photochemical and mild reaction conditions. This process gives good to excellent conversion under optimized reaction conditions. After completion of the reaction, Pd2+ is reduced to Pd0. Further, Pd0 can be easily converted into Pd2+ by heating with ammonium chloride at 400 °C for 30 min and the regenerated catalyst could be reused up to the third recycle with good catalytic activity. The catalysts (before and after reaction, as well as regenerated) were systematically characterized using Transmission Electron Microscopy, X-ray photoelectron spectroscopy, X-ray diffraction, temperature programmed reduction and DRUV-visible spectroscopy techniques.
异质PdCl2/TiO2在光
化学和温和反应条件下有效催化芳基
碘和烯烃之间的C-C键形成(Heck反应)。该过程在优化反应条件下提供了良好至优异的转化率。反应完成后,Pd2+被还原为Pd0。进一步地,Pd0能通过在400°C下与
氯化铵加热30分钟轻松转化为Pd2+,再生催化剂可在第三次循环中重复使用并保持良好的催化活性。催化剂(反应前后以及再生后)通过透射电子显微镜、X射线光电子能谱、X射线衍射、程序升温还原和紫外-可见光谱技术进行了系统的表征。