| Autor: |
Hu QQ; Center of Basic Molecular Science (CBMS), Department of Chemistry, Tsinghua University, Beijing 100084, China. mtzhang@mail.tsinghua.edu.cn., Chen QF; Center of Basic Molecular Science (CBMS), Department of Chemistry, Tsinghua University, Beijing 100084, China. mtzhang@mail.tsinghua.edu.cn., Zhang HT; Center of Basic Molecular Science (CBMS), Department of Chemistry, Tsinghua University, Beijing 100084, China. mtzhang@mail.tsinghua.edu.cn., Chen JY; Key Laboratory of Material Chemistry for Energy Conversion and Storage, Ministry of Education, Hubei Key Laboratory of Bioinorganic Chemistry and Materia Medica, Hubei Key Laboratory of Materials Chemistry and Service Failure, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, China. jiayi@hust.edu.cn., Liao RZ; Key Laboratory of Material Chemistry for Energy Conversion and Storage, Ministry of Education, Hubei Key Laboratory of Bioinorganic Chemistry and Materia Medica, Hubei Key Laboratory of Materials Chemistry and Service Failure, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, China. jiayi@hust.edu.cn., Zhang MT; Center of Basic Molecular Science (CBMS), Department of Chemistry, Tsinghua University, Beijing 100084, China. mtzhang@mail.tsinghua.edu.cn. |
| Abstrakt: |
The one-step oxidation of benzene to phenol represents a significant and promising advancement in modern industries focused on the production of high-value-added chemical products. Nevertheless, challenges persist in achieving sufficient catalytic selectivity and preventing over-oxidation. Inspired by copper enzymes, we present a nonsymmetric dicopper complex ([CuII2(TPMAN)(μ-OH)(H 2 O)] 3+ , 1) for the selective oxidation of benzene to phenol. Utilizing H 2 O 2 as the oxidant, complex 1 demonstrates remarkable catalytic activity (a TON of 14 000 within 29 hours) and selectivity exceeding 97%, comparable to the finest homogeneous catalyst derived from first-row transition metals. It is noteworthy that the significant substituent effect, alongside a negligible kinetic isotope effect (KIE = 1.05), radical trapping experiments, and an inconsistent standard selectivity test of the ˙OH radicals, all contradict the conventional Fenton mechanism and rebound pathway. Theoretical investigations indicate that the active Cu II (μ-O˙)Cu II -OH species generated through the cleavage of the O-O bond in the Cu II (μ-1,1-OOH)Cu I intermediate facilitates the hydroxylation of benzene via an electrophilic attack mechanism. The nonsymmetric coordination geometry is crucial in activating H 2 O 2 and in the process of O-O bond cleavage. |
