Co-Catalyzed Hydrofluorination of Alkenes: Photocatalytic Method Development and Electroanalytical Mechanistic Investigation

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(7), P. 4380 - 4392

Published: Feb. 1, 2024

The hydrofluorination of alkenes represents an attractive strategy for the synthesis aliphatic fluorides. This approach provides a direct means to form C(sp3)–F bonds selectively from readily available alkenes. Nonetheless, conducting using nucleophilic fluorine sources poses significant challenges due low acidity and high toxicity associated with HF poor nucleophilicity fluoride. In this study, we present new Co(salen)-catalyzed simple utilizing Et3N·3HF as sole source both hydrogen fluorine. process operates via photoredox-mediated polar-radical-polar crossover mechanism. We also demonstrated versatility method by effectively converting diverse array activated varying degrees substitution into hydrofluorinated products. Furthermore, successfully applied methodology 18F-hydrofluorination reactions, enabling introduction 18F potential radiopharmaceuticals. Our mechanistic investigations, conducted rotating disk electrode voltammetry DFT calculations, unveiled involvement carbocation CoIV–alkyl species viable intermediates during fluorination step, contribution each pathway depends on structure starting alkene.

Language: Английский

---

A review of frustrated Lewis pair enabled monoselective C–F bond activation

Chemical Science, Journal Year: 2024, Volume and Issue: 15(8), P. 2712 - 2724

Published: Jan. 1, 2024

Frustrated Lewis pair (FLP) bond activation chemistry has greatly developed over the last two decades since seminal report of metal-free reversible hydrogen activation. Recently, FLP systems have been utilized to allow monoselective C-F (at equivalent sites) in polyfluoroalkanes. The problem 'over-defluorination' functionalization polyfluoroalkanes (where multiple fluoro-positions are uncontrollably functionalized) a long-standing chemical fluorocarbon for 80 years. mediated is complementary other solutions address and offers several advantages unique opportunities. This perspective highlights some these opportunities places development into context wider effort overcome 'over-defluorination'.

Language: Английский

---

Recent developments on PET radiotracers for TSPO and their applications in neuroimaging

Acta Pharmaceutica Sinica B, Journal Year: 2020, Volume and Issue: 11(2), P. 373 - 393

Published: Aug. 25, 2020

The 18 kDa translocator protein (TSPO), previously known as the peripheral benzodiazepine receptor, is predominately localized to outer mitochondrial membrane in steroidogenic cells. Brain TSPO expression relatively low under physiological conditions, but upregulated response glial cell activation. As primary index of neuroinflammation, implicated pathogenesis and progression numerous neuropsychiatric disorders neurodegenerative diseases, including Alzheimer's disease (AD), amyotrophic lateral sclerosis (ALS), Parkinson's (PD), multiple (MS), major depressive disorder (MDD) obsessive compulsive (OCD). In this context, TSPO-targeted positron emission tomography (PET) tracers have been developed. Among them, several radioligands advanced clinical research studies. review, we will overview recent development PET tracers, focusing on radioligand design, radioisotope labeling, pharmacokinetics, imaging evaluation. Additionally, consider current limitations, well translational potential for future application radiopharmaceuticals. This review aims not only present challenges imaging, also provide a new perspective targeted tracer discovery efforts. Addressing these facilitate translation studies neuroinflammation associated with central nervous system diseases.

Language: Английский

---

Site‐Selective Late‐Stage Aromatic [¹⁸F]Fluorination via Aryl Sulfonium Salts

Angewandte Chemie International Edition, Journal Year: 2019, Volume and Issue: 59(5), P. 1956 - 1960

Published: Nov. 7, 2019

Site-selective functionalization of C-H bonds in small complex molecules is a long-standing challenge organic chemistry. Herein, we report broadly applicable and site-selective aromatic dibenzothiophenylation reaction. The conceptual advantage this transformation further demonstrated through the two-step [18 F]fluorination series marketed small-molecule drugs.

Language: Английский

---

Transpathology: molecular imaging-based pathology

European Journal of Nuclear Medicine and Molecular Imaging, Journal Year: 2021, Volume and Issue: 48(8), P. 2338 - 2350

Published: Feb. 13, 2021

Abstract Pathology is the medical specialty concerned with study of disease nature and causes, playing a key role in bridging basic researches clinical medicine. In course development, pathology has significantly expanded our understanding disease, exerted enormous impact on management patients. However, challenges facing pathology, inherent invasiveness pathological practice persistent concerns sample representativeness, constitute its limitations. Molecular imaging noninvasive technique to visualize, characterize, measure biological processes at molecular level living subjects. With continuous development equipment probes, enabled an increasingly precise evaluation pathophysiological changes. A new pathophysiology visualization system based forming shows great potential reform practice. Several improvements “trans-,” including trans-scale, transparency, translation, would be driven by this kind Pathological changes could evaluated trans-scale mode; tissues transparentized better present underlying information; translational research facilitated. Thus, transpathology greatly facilitate deciphering events multiscale perspective, supporting precision medicine future.

Language: Английский

---

Arginase as a Potential Biomarker of Disease Progression: A Molecular Imaging Perspective

International Journal of Molecular Sciences, Journal Year: 2020, Volume and Issue: 21(15), P. 5291 - 5291

Published: July 25, 2020

Arginase is a widely known enzyme of the urea cycle that catalyzes hydrolysis L-arginine to L-ornithine and urea. The action arginase goes beyond boundaries hepatic ureogenic function, being widespread through most tissues. Two isoforms coexist, type I (Arg1) predominantly expressed in liver II (Arg2) throughout extrahepatic By producing while competing with nitric oxide synthase (NOS) for same substrate (L-arginine), can influence endogenous levels polyamines, proline, NO•. Several pathophysiological processes may deregulate arginase/NOS balance, disturbing homeostasis functionality organism. Upregulated expression associated several pathological range from cardiovascular, immune-mediated, tumorigenic conditions neurodegenerative disorders. Thus, potential biomarker disease progression severity has recently been subject research studies regarding therapeutic efficacy inhibitors. This review gives comprehensive overview role current state development inhibitors, discussing as molecular imaging stimulating novel specific high-affinity probes.

Language: Английский

---

Metal‐organic framework‐based cancer theranostic nanoplatforms

View, Journal Year: 2020, Volume and Issue: 1(2)

Published: May 26, 2020

Abstract The rapid development of imaging technologies provides a visual diagnostic tool for scientists and surgeons to comprehensively accurately understand the pathogenesis pathological processes complicated diseases, especially cancer. Theranostic platforms integrating various treatment strategies diagnosis cancer have been extensively studied. Notably, metal‐organic frameworks (MOFs) – an emerging porous organic‐inorganic hybrid material composed metal ions/ion clusters as nodes organic ligands linkers bridged by coordination bonds widely used intelligent carriers theranostics in recent years due their fascinating properties, including facile synthesis, diverse compositions, high surface areas porosities, tailorable sizes, multiple physicochemical easy functionalization, good biocompatibility. This review summarizes advanced developments achievements MOFs smart theranostic effective guided monomodal technologies, optical imaging, magnetic resonance computed tomography positron emission photoacoustic multimodal technologies. Moreover, prospects critical challenges are also addressed.

Language: Английский

---

Metallaphotoredox aryl and alkyl radiomethylation for PET ligand discovery

Nature, Journal Year: 2020, Volume and Issue: 589(7843), P. 542 - 547

Published: Nov. 25, 2020

Language: Английский

---

Self‐Amplified Photodynamic Therapy through the ¹O₂‐Mediated Internalization of Photosensitizers from a Ppa‐Bearing Block Copolymer

Angewandte Chemie International Edition, Journal Year: 2019, Volume and Issue: 59(9), P. 3711 - 3717

Published: Dec. 6, 2019

Nanocarriers are employed to deliver photosensitizers for photodynamic therapy (PDT) through the enhanced penetration and retention effect, but disadvantages including premature leakage non-selective release of still exist. Herein, we report a

Language: Английский

---

19F- and 18F-arene deoxyfluorination via organic photoredox-catalysed polarity-reversed nucleophilic aromatic substitution

Nature Catalysis, Journal Year: 2020, Volume and Issue: 3(9), P. 734 - 742

Published: Aug. 24, 2020

Language: Английский

---