Xuan Zhang , Jia Liu , Langxing Liao , Zikuan Wang , Binju Wang
{"title":"铁的配位动力学使铁(II)/α-酮戊二酸依赖性非血红素酶中的选择性 C-N 偶联得以实现,但绕过了不需要的 C-H 羟基化反应","authors":"Xuan Zhang , Jia Liu , Langxing Liao , Zikuan Wang , Binju Wang","doi":"10.1016/S1872-2067(24)60064-1","DOIUrl":null,"url":null,"abstract":"<div><p>Non-heme Fe(II)/α-ketoglutarate (αKG)-dependent enzymes catalyze numerous C–H activation and functionalization reactions. However, how αKG-dependent non-heme enzymes catalyzed C–H functionalization beyond the hydroxylation is largely unknown. Here, we addressed this issue in Fe(II)/ αKG-dependent oxygenase TqaL<sub>Nc</sub>, which catalyzes the selective C–H amination but bypasses the thermodynamically favored C–H hydroxylation. Here, the extensive computational studies have shown that the aziridine formation involves the conformational change of the Fe(IV)=O species from the axial configuration to the equatorial one, the substrate deprotonation of NH<sub>3</sub><sup>+</sup> group to form the NH-ligated intermediate, the C–H activation by the equatorial Fe(IV)=O species. Such mechanistic scenario has been cross-validated by oxidation of various substrates by TqaL<sub>Nc</sub> and its variants, including the available experiments and our new experiments. While the presence of steric hindrance between the substrate and the second-sphere residues would inhibit the aziridination process, the intrinsic reactivity of aziridination <em>vs.</em> hydroxylation is dictated by the energy splitting between two key redox-active dπ* frontier molecular orbitals: dπ*<sub>Fe-N</sub> and dπ*<sub>Fe-OH</sub>. The present findings highlight the key roles of the coordination change and dynamics of iron cofactor in dictating the catalysis of non-heme enzymes and have far-reaching implications for the other non-heme Fe(II)/αKG-dependent enzymes catalyzed C–H functionalization beyond the hydroxylation.</p></div>","PeriodicalId":9832,"journal":{"name":"Chinese Journal of Catalysis","volume":"62 ","pages":"Pages 131-144"},"PeriodicalIF":15.7000,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Coordination dynamics of iron enables the selective C–N coupling but bypasses unwanted C–H hydroxylation in Fe(II)/α-ketoglutarate- dependent non-heme enzymes\",\"authors\":\"Xuan Zhang , Jia Liu , Langxing Liao , Zikuan Wang , Binju Wang\",\"doi\":\"10.1016/S1872-2067(24)60064-1\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>Non-heme Fe(II)/α-ketoglutarate (αKG)-dependent enzymes catalyze numerous C–H activation and functionalization reactions. However, how αKG-dependent non-heme enzymes catalyzed C–H functionalization beyond the hydroxylation is largely unknown. Here, we addressed this issue in Fe(II)/ αKG-dependent oxygenase TqaL<sub>Nc</sub>, which catalyzes the selective C–H amination but bypasses the thermodynamically favored C–H hydroxylation. Here, the extensive computational studies have shown that the aziridine formation involves the conformational change of the Fe(IV)=O species from the axial configuration to the equatorial one, the substrate deprotonation of NH<sub>3</sub><sup>+</sup> group to form the NH-ligated intermediate, the C–H activation by the equatorial Fe(IV)=O species. Such mechanistic scenario has been cross-validated by oxidation of various substrates by TqaL<sub>Nc</sub> and its variants, including the available experiments and our new experiments. While the presence of steric hindrance between the substrate and the second-sphere residues would inhibit the aziridination process, the intrinsic reactivity of aziridination <em>vs.</em> hydroxylation is dictated by the energy splitting between two key redox-active dπ* frontier molecular orbitals: dπ*<sub>Fe-N</sub> and dπ*<sub>Fe-OH</sub>. The present findings highlight the key roles of the coordination change and dynamics of iron cofactor in dictating the catalysis of non-heme enzymes and have far-reaching implications for the other non-heme Fe(II)/αKG-dependent enzymes catalyzed C–H functionalization beyond the hydroxylation.</p></div>\",\"PeriodicalId\":9832,\"journal\":{\"name\":\"Chinese Journal of Catalysis\",\"volume\":\"62 \",\"pages\":\"Pages 131-144\"},\"PeriodicalIF\":15.7000,\"publicationDate\":\"2024-07-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Chinese Journal of Catalysis\",\"FirstCategoryId\":\"92\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S1872206724600641\",\"RegionNum\":1,\"RegionCategory\":\"化学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"CHEMISTRY, APPLIED\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Chinese Journal of Catalysis","FirstCategoryId":"92","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S1872206724600641","RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CHEMISTRY, APPLIED","Score":null,"Total":0}
Coordination dynamics of iron enables the selective C–N coupling but bypasses unwanted C–H hydroxylation in Fe(II)/α-ketoglutarate- dependent non-heme enzymes
Non-heme Fe(II)/α-ketoglutarate (αKG)-dependent enzymes catalyze numerous C–H activation and functionalization reactions. However, how αKG-dependent non-heme enzymes catalyzed C–H functionalization beyond the hydroxylation is largely unknown. Here, we addressed this issue in Fe(II)/ αKG-dependent oxygenase TqaLNc, which catalyzes the selective C–H amination but bypasses the thermodynamically favored C–H hydroxylation. Here, the extensive computational studies have shown that the aziridine formation involves the conformational change of the Fe(IV)=O species from the axial configuration to the equatorial one, the substrate deprotonation of NH3+ group to form the NH-ligated intermediate, the C–H activation by the equatorial Fe(IV)=O species. Such mechanistic scenario has been cross-validated by oxidation of various substrates by TqaLNc and its variants, including the available experiments and our new experiments. While the presence of steric hindrance between the substrate and the second-sphere residues would inhibit the aziridination process, the intrinsic reactivity of aziridination vs. hydroxylation is dictated by the energy splitting between two key redox-active dπ* frontier molecular orbitals: dπ*Fe-N and dπ*Fe-OH. The present findings highlight the key roles of the coordination change and dynamics of iron cofactor in dictating the catalysis of non-heme enzymes and have far-reaching implications for the other non-heme Fe(II)/αKG-dependent enzymes catalyzed C–H functionalization beyond the hydroxylation.
期刊介绍:
The journal covers a broad scope, encompassing new trends in catalysis for applications in energy production, environmental protection, and the preparation of materials, petroleum chemicals, and fine chemicals. It explores the scientific foundation for preparing and activating catalysts of commercial interest, emphasizing representative models.The focus includes spectroscopic methods for structural characterization, especially in situ techniques, as well as new theoretical methods with practical impact in catalysis and catalytic reactions.The journal delves into the relationship between homogeneous and heterogeneous catalysis and includes theoretical studies on the structure and reactivity of catalysts.Additionally, contributions on photocatalysis, biocatalysis, surface science, and catalysis-related chemical kinetics are welcomed.