Zou Wenjing, Zhou Hongru, Wang Min
School of Chemistry, Dalian University of Technology, Dalian, 116024, Liaoning, P. R. China.
ChemSusChem. 2023 Oct 20;16(20):e202300727. doi: 10.1002/cssc.202300727. Epub 2023 Aug 10.
Selective C-O bond cleavage is an efficient way for the biomass valorization to value-added chemicals, but is challenged to be operated at room temperature via conventional thermal catalysis. Herein, inspired from the DNA biosynthesis which involves a radical-mediated spin-center shift (SCS) C-O bond cleavage process, we report a biomimetic room-temperature C-O bond cleavage of vicinal diol (HOCHCH-OH). We construct a Mn doped CdS (Mn/CdS) as a photocatalyst to mimic the biologic SCS process. The Mn site plays pivotal role: (1) accelerates the photo-induced carrier separation, promoting the hole-mediated C-H bond cleavage to generate carbon-centered radicals, and (2) serves as the binding site for -OH groups, making it to be an easier leaving group. Mn/CdS achieves 0.28 mmol g h of hydroxyacetone (HA) from glycerol dehydration at room temperature under visible light irradiation, which is 3.5-fold that over pristine CdS and 40-fold that over bulk MnS/CdS. This study provides a new biomimetic room-temperature C-O bond cleavage process, which is promising for the biomass valorization.
选择性C-O键裂解是生物质转化为增值化学品的有效途径，但通过传统热催化在室温下进行该反应面临挑战。在此，受涉及自由基介导的自旋中心转移（SCS）C-O键裂解过程的DNA生物合成启发，我们报道了一种邻二醇（HOCHCH-OH）的仿生室温C-O键裂解。我们构建了一种Mn掺杂的CdS（Mn/CdS）作为光催化剂来模拟生物SCS过程。Mn位点起着关键作用：（1）加速光生载流子分离，促进空穴介导的C-H键裂解以生成碳中心自由基，以及（2）作为-OH基团的结合位点，使其成为更易离去的基团。在可见光照射下，Mn/CdS在室温下通过甘油脱水可实现0.28 mmol g h的羟基丙酮（HA）产量，这是原始CdS的3.5倍，是块状MnS/CdS的40倍。本研究提供了一种新的仿生室温C-O键裂解过程，这对生物质转化具有广阔前景。
