Amorphous MoaZr0.8Ox-500 catalyzed selective oxidation of sulfides to sulfoxides mediated by 1O2 from direct heterolytic cleavage of H2O2

• Published in: Inorganic chemistry frontiers 2024-11, Vol.11 (23), p.8411-8420
• Main Authors: Li, Tong, Qin, Jiaheng, Zhang, Xueyao, Tang, Xiaoqi, Lv, Mingzhe, Mao, Weiwen, Dong, Linkun, Fan, Tongtong, Long, Yu, Ma, Jiantai
• Format: Article
• Language: English
• Subjects: Chemical synthesis; Cleavage; Fine chemicals; Hydrogen peroxide; Oxidation; Oxygen; Solid solutions; Sulfones; Sulfoxides; Zirconium dioxide
• ISSN: 2052-1545; 2052-1553
• DOI: 10.1039/d4qi02008a

Sulfoxides, a class of pharmaceuticals and fine chemicals of significant importance, are readily peroxidized to sulfones in the H2O2 system. Altering the intermediate oxygen species is the key to achieving selectivity regulation. Herein, Zr(OH)4 was used to support Mo species, after calcining at 500 °C, obtaining a unique amorphous composite oxide with Mo uniformly dispersed in the ZrO2 matrix (MoaZr0.8Ox-500). MoaZr0.8Ox-500 demonstrates enhanced catalytic proficiency, enabling the synthesis of sulfoxides within 30 minutes at 30 °C. Reactive oxygen species (ROS) quenching experiments and EPR spectra indicate that MoaZr0.8Ox-500 possesses the ability to rapidly and directly participate in the heterolytic cleavage of H2O2 to produce 1O2 without passing through the intermediate ·O2−, preventing the peroxidation of sulfoxides to sulfones. Additionally, the prevalence of basic sites in MoaZr0.8Ox-500 is conducive to proton transfer, which plays a significant role in the heterolytic cleavage of H2O2. Furthermore, MoaZr0.8Ox-500 exhibits excellent reproducibility, scalability, and broad substrate applicability. This study provides new insights into the selective regulation of the sulfide oxidation reaction, as well as the preparation of amorphous solid solution.