Photoiodization of toluene in a microflow platform
Benzyl iodide, an important organic synthesis intermediate, has high reaction activity as well as high commercial value due to its weakest carbon-halogen bond. However, the development of direct iodination of toluene for benzyl iodide is limited by the fact that the C-I bond is easily decomposed under heat or light. In this work, the photoiodination of toluene to synthesize benzyl iodide in the I 2 /PhI(OAc) 2 / t BuOH system was carefully investigated in the flow photoreactor under LEDs irradiation. The reaction window suitable for the reaction kinetic characteristics recognition was revealed with the considerations of the effects of various parameters including light color, light intensity, reaction temperature, residence time, and usage of each substrate. And an optimized result is to achieve 95.83 % of yield and over 99 % of selectivity under a red light with 2.05 mW/cm 2 of light intensity at 80 o C after 15 min reaction. The reaction kinetic model coupling the iodination reaction (photo and thermal reaction) with the decomposition reaction is established, which fits well the experimental results and provides fundamentals for process design and optimization. Graphical abstract
危险品化学品经营许可证（带存储）