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1.
Nano Lett ; 24(28): 8587-8594, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38967395

RESUMO

Single-unit cell (1 UC) FeSe interfaced with TiOx or FeOx exhibits significantly enhanced superconductivity compared to that of bulk FeSe, with interfacial electron-phonon coupling (EPC) playing a crucial role. However, the reduced dimensionality in 1 UC FeSe, which may drive superconducting fluctuations, complicates our understanding of the enhancement mechanisms. We construct a new superconducting interface, 1 UC FeSe/SrVO3/SrTiO3. Here, the itinerant electrons of highly metallic SrVO3 films can screen all high-energy Fuchs-Kliewer phonons, including those of SrTiO3, making it the first FeSe/oxide system with screened interfacial EPC while maintaining the 1 UC FeSe thickness. Despite comparable doping levels, the heavily electron-doped 1 UC FeSe/SrVO3 exhibits a pairing temperature (Tg ∼ 48 K) lower than those of FeSe/SrTiO3 and FeSe/LaFeO3. Our findings disentangle the contributions of interfacial EPC from dimensionality in terms of enhancing Tg in FeSe/oxide interfaces, underscoring the critical importance of interfacial EPC. This FeSe/VOx interface also provides a platform for studying interfacial superconductivity.

2.
Natl Sci Rev ; 11(8): nwae194, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39007006

RESUMO

Superconducting infinite-layer (IL) nickelates offer a new platform for investigating the long-standing problem of high-temperature superconductivity. Many models were proposed to understand the superconducting mechanism of nickelates based on the calculated electronic structure, and the multiple Fermi surfaces and multiple orbitals involved create complications and controversial conclusions. Over the past five years, the lack of direct measurements of the electronic structure has hindered the understanding of nickelate superconductors. Here we fill this gap by directly resolving the electronic structures of the parent compound LaNiO2 and superconducting La0.8Ca0.2NiO2 using angle-resolved photoemission spectroscopy. We find that their Fermi surfaces consist of a quasi-2D hole pocket and a 3D electron pocket at the Brillouin zone corner, whose volumes change upon Ca doping. The Fermi surface topology and band dispersion of the hole pocket closely resemble those observed in hole-doped cuprates. However, the cuprate-like band exhibits significantly higher hole doping in superconducting La0.8Ca0.2NiO2 compared to superconducting cuprates, highlighting the disparities in the electronic states of the superconducting phase. Our observations highlight the novel aspects of the IL nickelates, and pave the way toward the microscopic understanding of the IL nickelate family and its superconductivity.

3.
Nano Lett ; 24(27): 8303-8310, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38934420

RESUMO

The discovery of interfacial superconductivity in monolayer FeSe/oxides has spurred intensive research interest. Here we not only extend the FeSe/FeOx superconducting interface to FeSe/NdFeO3 but also establish robust interface-enhanced superconductivity at a very low doping level. Specifically, well-annealed FeSe/NdFeO3 exhibits a low doping level of 0.038-0.046 e-/Fe with a larger superconducting pairing gap without a nematic gap, indicating an enhancement of the enhanced superconducting pairing strength and suppression of nematicity by the FeSe/FeOx interface compared with those of thick FeSe films. These results improve our understanding of the roles of the oxide interface in the low-electron-doped regime.

4.
J Am Chem Soc ; 146(11): 7178-7184, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38466344

RESUMO

In the field of catalytic asymmetric synthesis, the less-treated path lies in oxidative catalytic asymmetric transformations. The hurdles of pinpointing the appropriate chemical oxidants and addressing their compatibility issues with catalysts and functionalities present significant challenges. Organic electrochemistry, employing traceless electrons for redox reactions, is underscored as a promising solution. However, the commonly used electrolysis in batch cells introduces its own set of challenges, hindering the advancement of electrochemical asymmetric catalysis. Here we introduce a microfluidic electrochemistry platform with single-pass continuous flow reactors that exhibits a wide-ranging applicability to various oxidative asymmetric catalytic transformations. This is exemplified through the sulfenylation of 1,3-dicarbonyls, dehydrogenative C-C coupling, and dehydrogenative alkene annulation processes. The unique properties of microfluidic electrochemical reactors not only eliminate the need for chemical oxidants but also enhance reaction efficiency and reduce the use of additives and electrolytes. These salient features of microfluidic electrochemistry expedite the discovery and development of oxidative asymmetric transformations. In addition, the continuous production facilitated by parallel single-pass reactors ensures straightforward reaction upscaling, removing the necessity for reoptimization across various scales, as evidenced by direct translation from milligram screening to hectogram asymmetric synthesis.

5.
Int Dent J ; 74(4): 836-846, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38369441

RESUMO

OBJECTIVE: Pulp regeneration with bioactive dentin-pulp complex has been a research hotspot in recent years. Stem cell therapy provided an interest strategy to regenerate the dental-pulp complex. Hence, this study aimed to evaluate the effects of photosensitive gelatin methacrylate (GelMA) hydrogel encapsulating dental pulp stem cells (DPSCs) and silver nanoparticles (AgNPs) for dental pulp regeneration in vitro. METHODS: First, the AgNPs@GelMA hydrogels were prepared by lithium phenyl-2,4,6-trimethyl-benzoyl phosphinate (LAP) initiation via blue-light emitting diode light. The physical and chemical properties of AgNPs@GelMA hydrogels were comprehensively analysed via scanning electron microscopy (SEM), and mechanical characterisation, such as swelling ability, degradation properties, and AgNP release profile. Then, AgNPs@GelMA hydrogels encapsulated DPSCs were used to establish an AgNPs@GelMA biomimetic complex, further analysing its biocompatibility, antibacterial properties, and angiogenic capacity in vitro. RESULTS: The results indicated that GelMA hydrogels demontrated optimal characteristics with a monomer:LAP ratio of 16:1. The physico-chemical properties of AgNPs@GelMA hydrogels did not change significantly after loading with AgNPs. There was no significant difference in AgNP release rate amongst different concentrations of AgNPs@GelMA hydrogels. Fifty to 200 µg/mL AgNPs@GelMA hydrogels could disperse E faecalis biofilm and reduce its metabolic activity . Furthermore, cell proliferation was arrested in 100 and 200 µg/mL AgNPs@GelMA hydrogels. The inhibition of 50 µg/mL AgNPs@GelMA hydrogels on E faecalis biofilm was above 50%, and the cell viability of the hydrogels was higher than 90%. The angiogenesis assay indicated that AgNPs@GelMA hydrogels encapsulating DPSCs could induce the formation of capillary-like structures and express angiogenic markers CD31, vascular endothelial growth factor , and von willebrand factor (vWF) in vitro. CONCLUSIONS: Results of this study indicate that 50 µg/mL AgNPs@GelMA hydrogels encapsulating DPSCs had significant antibacterial properties and angiogenic capacity, which could provide a significant experimental basis for the regeneration of the dentin-pulp complex.


Assuntos
Polpa Dentária , Gelatina , Hidrogéis , Nanopartículas Metálicas , Regeneração , Prata , Células-Tronco , Polpa Dentária/citologia , Polpa Dentária/efeitos dos fármacos , Humanos , Hidrogéis/química , Nanopartículas Metálicas/uso terapêutico , Células-Tronco/efeitos dos fármacos , Regeneração/efeitos dos fármacos , Gelatina/química , Metacrilatos/química , Antibacterianos/farmacologia , Microscopia Eletrônica de Varredura , Proliferação de Células/efeitos dos fármacos
6.
Angew Chem Int Ed Engl ; 63(6): e202313273, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-37906439

RESUMO

The difunctionalization of alkenes-a process that installs two functional groups in a single operation and transforms chemical feedstocks into value-added products-is one of the most appealing synthetic methods in contemporary chemistry. However, the introduction of two distinct functional groups via two readily accessible nucleophiles remains a formidable challenge. Existing intermolecular alkene azidocyanation methods, which primarily focus on aryl alkenes and rely on stoichiometric chemical oxidants. We report herein an unprecedented electrochemical strategy for alkene azidocyanation that is compatible with both alkyl and aryl alkenes. This is achieved by harnessing the finely-tuned anodic electron transfer and the strategic selection of copper/ligand complexes. The reactions of aryl alkenes were rendered enantioselective by employing a chiral ligand. Crucially, the mild conditions and well-regulated electrochemical process assure exceptional tolerance for various functional groups and substrate compatibility with both terminal and internal alkyl alkenes.

7.
Angew Chem Int Ed Engl ; 62(40): e202310138, 2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37590086

RESUMO

The selective oxygenation of ubiquitous C(sp3 )-H bonds remains a highly sought-after method in both academia and the chemical industry for constructing functionalized organic molecules. However, it is extremely challenging to selectively oxidize a certain C(sp3 )-H bond to afford alcohols due to the presence of multiple C(sp3 )-H bonds with similar strength and steric environment in organic molecules, and the alcohol products being prone to further oxidation. Herein, we present a practical and cost-efficient electrochemical method for the highly selective monooxygenation of benzylic C(sp3 )-H bonds using continuous flow reactors. The electrochemical reactions produce trifluoroacetate esters that are resistant to further oxidation but undergo facile hydrolysis during aqueous workup to form benzylic alcohols. The method exhibits a broad scope and exceptional site selectivity and requires no catalysts or chemical oxidants. Furthermore, the electrochemical method demonstrates excellent scalability by producing 115 g of one of the alcohol products. The high site selectivity of the electrochemical method originates from its unique mechanism to cleave benzylic C(sp3 )-H bonds through sequential electron/proton transfer, rather than the commonly employed hydrogen atom transfer (HAT).

8.
J Am Chem Soc ; 145(34): 18753-18759, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37581933

RESUMO

The asymmetric difunctionalization of alkenes, a method transforming readily accessible alkenes into enantioenriched chiral structures of high value, has long been a focal point of organic synthesis. Despite tremendous efforts in this domain, it remains a considerable challenge to devise enantioselective oxidative dicarbofunctionalization of alkenes, even though these transformations can utilize stable and unfunctionalized functional group donors. In this context, we report herein a photoelectrocatalytic method for the enantioselective heteroarylcyanation of aryl alkenes, which employs unfunctionalized heteroarenes through C-H functionalization. The photoelectrochemical asymmetric catalysis (PEAC) method combines photoredox catalysis and asymmetric electrocatalysis to facilitate the formation of two C-C bonds operating via hydrogen (H2) evolution and obviating the need for external chemical oxidants.

9.
J Am Chem Soc ; 144(44): 20201-20206, 2022 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-36315651

RESUMO

The development of efficient and sustainable methods for decarboxylative transformations is of great importance due to the ease of availability and nontoxicity of carboxylic acids. Despite tremendous efforts in this area, it remains challenging to develop enantioselective transformations direct from carboxylic acids. Herein we disclose a photoelectrocatalytic method for the direct and enantioselective decarboxylative cyanation. The photoelectrochemical reactions convert carboxylic acids to enantioenriched nitriles by employing cerium/copper relay catalysis with a cerium salt for catalytic decarboxylation and a chiral copper complex for stereoselective C-CN formation.


Assuntos
Cério , Cobre , Estereoisomerismo , Catálise , Ácidos Carboxílicos
10.
Artigo em Inglês | MEDLINE | ID: mdl-36011536

RESUMO

Health geography provides a relational approach to understanding elders' wellbeing experience in relation to place. That the migrating grandparents move between their home and their adult children's home to support their children's life in the migrating city provides a particular pattern to supplement the place-based wellbeing literature. How they negotiate their wellbeing remains to be observed in the daily home-making practices related to their two homes. This study conducted in-depth interviews with 35 migrating grandparents and nine of their adult children and conducted extensive field notes in Shanghai from 2020 to 2022. Through thematic analysis, it finds that the migrating grandparents met a series of differences, challenges and tensions in the material, social and emotional home-making practices brought by the separation and rotation between their own and their children's homes. It weakens their physical, social and mental wellbeing. However, they take some initiatives to overcome and relieve these tensions. Therefore, accompanied by sacrifices and negotiations, they also obtain sustained material, social and spiritual-emotional values to negotiate a suboptimal experience of wellbeing. This study contributes to the intersection of elderly wellbeing and home-making studies by revealing the complex and ongoing inter-relationships between migrating grandparents and home in the rotating lifestyle.


Assuntos
Avós , Adulto , Idoso , Humanos , Filhos Adultos , China , Divórcio , Avós/psicologia , Negociação
11.
Nat Commun ; 13(1): 3945, 2022 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-35803941

RESUMO

The direct hydroxylation of arene C-H bonds is a highly sought-after transformation but remains an unsolved challenge due to the difficulty in efficient and regioselective C-H oxygenation and high reactivity of the phenolic products leading to overoxidation. Herein we report electrochemical C-H hydroxylation of arenes in continuous flow for the synthesis of phenols. The method is characterized by broad scope (compatible with arenes of diverse electronic properties), mild conditions without any catalysts or chemical oxidants, and excellent scalability as demonstrated by the continuous production of 1 mol (204 grams) of one of the phenol products.


Assuntos
Oxidantes , Fenóis , Catálise , Hidroxilação , Oxidantes/química , Fenóis/química
12.
J Am Chem Soc ; 144(27): 11980-11985, 2022 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-35772000

RESUMO

The 1,2-diamine motif is prevalent in natural products, small-molecule pharmaceuticals, and catalysts for asymmetric synthesis. Transition metal catalyzed alkene diazidation has evolved to be an attractive strategy to access vicinal primary diamines but remains challenging, especially for practical applications, due to the restriction to a certain type of olefins, the frequent use of chemical oxidants, and the requirement for high loadings of metal catalysts (1 mol % or above). Herein we report a scalable Cu-electrocatalytic alkene diazidation reaction with 0.02 mol % (200 ppm) of copper(II) acetylacetonate as the precatalyst without exogenous ligands. In addition to its use of low catalyst loading, the electrocatalytic method is scalable, compatible with a broad range of functional groups, and applicable to the diazidation of α,ß-unsaturated carbonyl compounds and mono-, di-, tri-, and tetrasubstituted unactivated alkenes.


Assuntos
Alcenos , Diaminas , Alcenos/química , Catálise , Cobre/química , Diaminas/química , Ligantes
13.
Cancer Manag Res ; 14: 1703-1711, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35585940

RESUMO

Objective: Retrospective study on the safety and efficacy of anlotinib in the treatment of advanced leiomyosarcoma in real-world. Methods: Clinical data were collected from patients suffered from advanced leiomyosarcoma who received anlotinib treatment in Cancer Hospital of the University of Chinese Academy of Sciences from January 2018 to December 2020. Objective response rate (ORR) and disease control rate (DCR) were analyzed according to the RECIST 1.1 criteria. The progression free survival (PFS), overall survival (OS) and adverse reactions were recorded and calculated. Results: A total of 19 patients (14 female, 5 male) were enrolled, 3 (15.8%) achieved partial response (PR), 11 (57.9%) achieved stable disease (SD), with an ORR of 15.8%, a DCR of 73.7%, a median PFS of 4.1 months (95% CI: 3.0~5.2) and a median OS of 23.5 months (95% CI: 14.2~32.7). The majority of adverse events were grade 1/2, the most common grade 3/4 adverse events were hand-foot syndrome (12.5%), hypertension (5.3%) and oral ulcer (5.3%). Conclusion: Our results forecast that anlotinib is effective, safe and alternative in treatment of advanced leiomyosarcoma in real-world, combined with immunotherapy may become a potential treatment option. Further, more prospective randomized controlled trials are needed to confirm these findings.

14.
Genet Test Mol Biomarkers ; 26(4): 239-248, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35481971

RESUMO

Background: The performance of methylated SEPT9 (mSEPT9) in lower gastrointestinal (GI) cancer (colorectal cancer) has been extensively investigated; however, its performance in upper GI cancer (esophageal cancer and gastric cancer) and the comparison with lower GI cancer have rarely been studied. Methods: A total of 1854 subjects, including 344 upper GI cancer patients, 459 lower GI cancer patients, and 1051 noncancer subjects, were recruited in this prospective cohort study. A modified single polymerase chain reaction test for detecting mSEPT9 was used for plasma detection. Results: The sensitivity of mSEPT9 for upper and lower GI cancers was 45.3% and 74.8%, and the corresponding specificities were 85.6% and 86.5%, with areas under curve (AUC) of 0.71 and 0.80, respectively. mSEPT9 exhibited lower sensitivity in stage I than stage II-IV cancer, while no difference in sensitivity was observed for different locations in upper or lower GI cancer. No difference in sensitivity was found among gross classifications, pathological classifications, and differentiation in upper GI cancer, but a higher sensitivity in infiltrative cancer and moderate and poorly differentiated cancers was observed in the lower GI. No difference in sensitivity was found between male and female in both cancers, while sensitivity increased with age for both cancers. Cancer antigen 724 (CA724) showed the highest sensitivity for upper GI cancers, and carcinoembryonic antigen (CEA) showed the highest sensitivity for lower GI cancers. The combination of CA724 with mSEPT9 increased the sensitivity to 67.5% in upper GI cancers, and the combination of mSEPT9 with CEA increased the sensitivity to 85.4% in lower GI cancers, with an AUC of 0.90 and 0.95, respectively. Conclusions: mSEPT9 exhibited a higher sensitivity in lower GI cancers than upper GI cancers. The combination of mSEPT9 with protein markers significantly enhanced the detection sensitivity in both cancers.


Assuntos
Neoplasias Colorretais , Neoplasias Gastrointestinais , Septinas/metabolismo , Biomarcadores Tumorais/genética , Antígeno Carcinoembrionário/metabolismo , Neoplasias Colorretais/diagnóstico , Feminino , Neoplasias Gastrointestinais/genética , Neoplasias Gastrointestinais/patologia , Humanos , Masculino , Estadiamento de Neoplasias , Estudos Prospectivos , Septinas/genética
15.
Angew Chem Int Ed Engl ; 61(14): e202115954, 2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35129253

RESUMO

The direct functionalization of allylic C-H bonds with nucleophiles minimizes pre-functionalization and converts inexpensive, abundantly available materials to value-added alkenyl-substituted products but remains challenging. Here we report an electrocatalytic allylic C-H alkylation reaction with carbon nucleophiles employing an easily available cobalt-salen complex as the molecular catalyst. These C(sp3 )-H/C(sp3 )-H cross-coupling reactions proceed through H2 evolution and require no external chemical oxidants. Importantly, the mild conditions and unique electrocatalytic radical process ensure excellent functional group tolerance and substrate compatibility with both linear and branched terminal alkenes. The synthetic utility of the electrochemical method is highlighted by its scalability (up to 200 mmol scale) under low loading of electrolyte (down to 0.05 equiv) and its successful application in the late-stage functionalization of complex structures.

16.
J Am Chem Soc ; 144(5): 2343-2350, 2022 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-35102740

RESUMO

Cyclopropane is a prevalent structural unit in natural products and bioactive compounds. While the transition metal-catalyzed alkene cyclopropanation of functionalized compounds such as α-diazocarbonyl derivatives has been well established and provides straightforward access to cyclopropanes, cyclopropanation directly from the more stable and simpler methylene compounds has remained an unsolved challenge despite the highly desirable benefits of minimal prefunctionalization and increased operational safety. Herein we report an electrocatalytic strategy for the cyclopropanation of active methylene compounds, employing an organic catalyst. The method shows a broad substrate scope and excellent scalability, requires no metal catalyst or external chemical oxidant, and provides convenient access to several types of cyclopropane-fused heterocyclic and carbocyclic compounds. Mechanistic investigations suggest that the reactions proceed through a radical-polar crossover process to form the two new carbon-carbon bonds in the nascent cyclopropane ring.

17.
ChemSusChem ; 15(10): e202102603, 2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35092355

RESUMO

Two-dimensional metal-organic nanosheets (2D MONs) are an emerging class of ultrathin, porous, and crystalline materials. The organic/inorganic hybrid nature offers MONs distinct advantages over other inorganic nanosheets in terms of diversity of organic ligands and metal notes. Compared to bulk three-dimensional metal-organic frameworks, 2D MONs possess merits of high density and readily accessible catalytic sites, reduced diffusion pathways for reactants/products, and fast electron transport. These features endow MONs with enhanced physical/chemical properties and are ideal for heterogeneous catalysis. In this Review, state-of-the-art synthetic methods for the fabrication of 2D MONs were summarized. The advances of 2D MONs-based materials for electrocatalysis and photocatalysis, including hydrogen evolution reaction (HER), oxygen evolution reaction (OER), oxygen reduction reaction (ORR), carbon dioxide reduction reaction (CO2 RR), and electro-/photocatalytic organic transformations were systematically discussed. Finally, the challenges and perspectives regarding future design and synthesis of 2D MONs for high-performance electrocatalysis and photocatalysis were provided.


Assuntos
Estruturas Metalorgânicas , Catálise , Hidrogênio , Estruturas Metalorgânicas/química , Metais/química , Oxigênio/química
18.
Biochem Genet ; 60(3): 1095-1106, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34792704

RESUMO

This study aimed to explore the roles and relationship between FUsed in Sarcoma (FUS)-C/EBP HOmologous Protein (CHOP), microRNA (miR)-486 and cyclin dependent kinase 4 (CDK4) in myxoid liposarcoma, and determined whether FUS-CHOP can regulate proliferation and apoptosis of myxoid liposarcoma cells by regulating miR-486/CDK4 axis. The levels of miR-486, CDK4 and FUS-CHOP in myxoid liposarcoma samples/adjacent normal muscle tissues and myxoid liposarcoma/human adipose-derived stem cell line were evaluated using reverse transcription-quantitative polymerase chain reaction and western blotting. Cell proliferation and apoptosis were performed using 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide and flow cytometry, respectively. Furthermore, the apoptosis-related proteins were determined using Western blot assay. We found that miR-486 was down-regulated, FUS-CHOP and CDK4 were up-regulated in myxoid liposarcoma tissues and myxoid liposarcoma cell lines. Moreover, FUS-CHOP-siRNA distinctly suppressed FUS-CHOP level and increased miR-486 levels in 1955/91 cells. Our results demonstrated that knockdown of FUS-CHOP by siRNA inhibited 1955/91 growth, promoted cell apoptosis and enhanced cleaved Caspase3 protein expression. However, all these data were reversed by miR-486 inhibitor. Similarly, compared to mimic control, miR-486 mimic markedly reduced 1955/91 cells growth, induced cell apoptosis and fortified cleaved Caspase3 level, while these results were abolished by CDK4-plasmid. Collectively, our observations clearly suggested that FUS-CHOP regulated myxoid liposarcoma cell proliferation and apoptosis by the regulation of miR-486/CDK4 axis, indicating the potential use of FUS-CHOP-siRNA as a promising therapy for myxoid liposarcoma.


Assuntos
Lipossarcoma Mixoide , MicroRNAs , Fator de Transcrição CHOP/genética , Quinase 4 Dependente de Ciclina/genética , Quinase 4 Dependente de Ciclina/metabolismo , Humanos , Lipossarcoma Mixoide/genética , Lipossarcoma Mixoide/metabolismo , MicroRNAs/genética , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/metabolismo , RNA Interferente Pequeno/genética , Proteína FUS de Ligação a RNA/genética , Proteína FUS de Ligação a RNA/metabolismo , Fator de Transcrição CHOP/metabolismo
19.
Nat Commun ; 12(1): 6629, 2021 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-34785664

RESUMO

The development of efficient and sustainable methods for carbon-phosphorus bond formation is of great importance due to the wide application of organophosphorus compounds in chemistry, material sciences and biology. Previous C-H phosphorylation reactions under nonelectrochemical or electrochemical conditions require directing groups, transition metal catalysts, or chemical oxidants and suffer from limited scope. Herein we disclose a catalyst- and external oxidant-free, electrochemical C-H phosphorylation reaction of arenes in continuous flow for the synthesis of aryl phosphorus compounds. The C-P bond is formed through the reaction of arenes with anodically generated P-radical cations, a class of reactive intermediates remained unexplored for synthesis despite intensive studies of P-radicals. The high reactivity of the P-radical cations coupled with the mild conditions of the electrosynthesis ensures not only efficient reactions of arenes of diverse electronic properties but also selective late-stage functionalization of complex natural products and bioactive compounds. The synthetic utility of the electrochemical method is further demonstrated by the continuous production of 55.0 grams of one of the phosphonate products.

20.
J Org Chem ; 86(22): 15845-15846, 2021 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-34794313
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