Zhou Ying-Hua, Jiang Chen-Chen, Yu Zhou, Wang Ya-Hao, Zheng Ju-Fang, Zhou Xiao-Shun
Jinhua Education College, Jinhua 321000, China.
Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, Institute of Physical Chemistry, Zhejiang Normal University, Jinhua 321004, China.
Anal Methods. 2023 Feb 9;15(6):771-777. doi: 10.1039/d2ay02060b.
Electroreductive dehalogenation as an efficient and green approach has attracted much attention in pollution remediation. Herein, we have employed a shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS) technique to probe the electroreductive dehalogenation process of aryl halides with thiol groups at Ag/aqueous solution interfaces. It is found that 4-bromothiophenol (BTP) and 4-chlorothiophenol (CTP) can turn into mixed products of 4,4'-biphenyldithiol (BPDT) and thiophenol (TP) as the electrode potential decreases. The conversion ratios estimated from the Raman intensity variations of C-Cl and C-Br vibrations are 44% and 58% for CTP and BTP in neutral solution, respectively. Furthermore, the quantitative analysis of benzene ring vibrations reveals a C-C cross coupling between the benzene free radical intermediate and adjacent TP product, which results in increased selectivity for biphenyl products at negative potentials.
电还原脱卤作为一种高效且绿色的方法，在污染修复领域备受关注。在此，我们采用了壳层隔离纳米粒子增强拉曼光谱（SHINERS）技术，来探测在银/水溶液界面上带有硫醇基团的芳基卤化物的电还原脱卤过程。研究发现，随着电极电位降低，4-溴硫酚（BTP）和4-氯硫酚（CTP）会转变为4,4'-联苯二硫醇（BPDT）和硫酚（TP）的混合产物。从中性溶液中C-Cl和C-Br振动的拉曼强度变化估算出的CTP和BTP的转化率分别为44%和58%。此外，对苯环振动的定量分析揭示了苯自由基中间体与相邻TP产物之间的C-C交叉偶联，这导致在负电位下对联苯产物的选择性增加。
