Article
Chemistry, Organic
Hao Xu, Cai-Yu He, Bo-Jie Huo, Jia-Wen Jing, Chengping Miao, Weidong Rao, Xue-Qiang Chu, Xiaocong Zhou, Zhi-Liang Shen
Summary: In this study, a cross-electrophile coupling of aryl thiols with aryl bromides was reported, where C-S bond activation occurred instead of S-H bond cleavage, leading to the formation of thioethers as the major products. The reaction proceeded effectively with a nickel catalyst, magnesium turnings, and lithium chloride in THF at room temperature, and a variety of structurally diverse biaryls were obtained in moderate to good yields.
ORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Applied
Miao Yu, Long Zhen, Liqin Jiang
Summary: A cobalt-catalyzed cascade reaction has been developed for the synthesis of 3-alkyl-2(3H)-benzothiazolones in good yields. This method avoids the use of bad-smell and toxic reagents. Mechanistic studies reveal that the reaction involves hydrolysis followed by dehydrogenative coupling to form a C-S bond through radical processes.
ADVANCED SYNTHESIS & CATALYSIS
(2022)
Article
Chemistry, Multidisciplinary
Andrew J. Greener, Patrycja Ubysz, Will Owens-Ward, George Smith, Ivan Ocana, Adrian C. Whitwood, Victor Chechik, Michael J. James
Summary: This study describes the design and development of an oxime-based hydroxylation reagent that can selectively convert aryl halides into phenols under simple, transition-metal-free conditions. The key to success lies in identifying a reducing oxime anion that can interact and couple with open-shell aryl radicals. Experimental and computational studies support the proposed radical-nucleophilic substitution chain mechanism.
Article
Biochemistry & Molecular Biology
Hyun Ji Han, Suh Youn Park, So Eun Jeon, Jae Seok Kwak, Ji Hye Lee, Ashok Kumar Jaladi, Hyonseok Hwang, Duk Keun An
Summary: In this study, a green hydroboration protocol was developed for the reduction of esters, nitriles, and imines at room temperature using pinacolborane as the reducing agent and a commercially available Grignard reagent as the catalyst. This method eliminates the need for complex ligand systems and elevated temperatures, providing an effective method for the reduction at room temperature.
Article
Chemistry, Multidisciplinary
Takeshi Fujita, Yutaro Kobayashi, Ikko Takahashi, Ryutaro Morioka, Tomohiro Ichitsuka, Junji Ichikawa
Summary: Nickel-catalyzed reductive cross-coupling of allylic difluorides with aryl iodides was successfully achieved, leading to the synthesis of a series of gamma-arylated monofluoroalkenes with moderate to high yields and high Z-selectivities. Mechanistic studies indicated that the cleavage of C-I bonds in aryl iodides and C-F bonds in allylic difluorides occurred through oxidative addition and beta-fluorine elimination, respectively.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Chemistry, Organic
Quentin D. Tercenio, Erik J. Alexanian
Summary: The nickel-catalyzed reductive coupling of allyl alcohols with chiral, nonracemic alkyl tosylates reported in this study delivers valuable allylation products with high levels of stereospecificity across a range of substrates. The catalytic system, consisting of a simple nickel salt and a commercially available reductant, represents a rare example of a cross-coupling involving the C-O bonds of two electrophiles.
Article
Chemistry, Multidisciplinary
Pui Kin Tony Lo, Michael C. Willis
Summary: This study presents a new redox-neutral Ni(II)-catalyzed reaction system for the addition of (hetero)aryl boroxines to N-sulfinyltritylamine to produce sulfinamide products. The initially formed sulfinamides can be further transformed into various compounds through chlorination and hydrolysis. These transformations can all be conducted through one-pot procedures.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Inorganic & Nuclear
Fei Fan, Lixing Zhao, Meiming Luo, Xiaoming Zeng
Summary: Chemically inert C(aryl)-F bonds have been successfully cleaved and coupled with unreactive C(aryl)-O bonds using chromium catalysis, enabling high selectivity and efficiency for cross-electrophile coupling.
Article
Chemistry, Multidisciplinary
Giuseppe Dilauro, Francesco Messa, Fabio Bona, Serena Perrone, Antonio Salomone
Summary: A simple cobalt complex, Co(phen)Cl₂, has been found to be a highly efficient and cost-effective precatalyst for various cross-coupling reactions involving aromatic and aliphatic organoaluminum reagents with aryl, heteroaryl, and alkyl bromides. New C(sp²)-C(sp²) and C(sp²)-C(sp³) bonds can be formed in good to excellent yields and high chemoselectivity under mild reaction conditions.
CHEMICAL COMMUNICATIONS
(2021)
Review
Chemistry, Multidisciplinary
Ewa Pietrasiak, Eunsung Lee
Summary: Examples of Grignard reagents obtained by C-F bond activation with magnesium have been widely reported in the literature over the past century. Efforts have been made to prepare highly active forms of magnesium due to the high bond dissociation energy of the C-F bond. Modern approaches involve the use of Mg(i)-Mg(i) dimers and transition metal catalysts for C-F bond activation, followed by transmetallation with a magnesium salt.
CHEMICAL COMMUNICATIONS
(2022)
Article
Chemistry, Physical
Sanita B. Tailor, Mattia Manzotti, Gavin J. Smith, Sean A. Davis, Robin B. Bedford
Summary: The cobalt-catalyzed Suzuki biaryl cross-coupling reaction using alkoxide bases, with strict stoichiometric control and selection of the right boron ester, is shown to be achievable. Excessive alkoxide bases or lithium additives can inhibit or poison the catalyst, while a neopentane diol-based boron ester is crucial for optimal performance.Mechanistic and computational studies have been carried out to investigate the reaction mechanism and explain unexpected observations.
Article
Chemistry, Organic
Chuntao Zhong, Mengna Liu, Xianchao Qiu, Hao Wei, Benqiang Cui, Yanhui Shi, Changsheng Cao
Summary: A nickel-catalyzed cross-coupling reaction between aryl methyl sulfides and aryl bromides has been developed to efficiently access biaryls. The method has a wide scope of substrates and is scalable, with commercially available aryl bromides being used without the need for preparation of organometallic reagents. This reaction has high application value.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Physical
Haifeng Chen, Chen Zhu, Huifeng Yue, Magnus Rueping
Summary: An efficient cobalt-catalyzed carbon-germanium bond formation method has been developed, providing access to a wide range of functionalized germane-containing compounds. This method shows a broad scope and good tolerance toward various functional groups, and is conducted under mild reaction conditions. Mechanistic studies shed light on the unexpected reaction pathway and sequential activation of different electrophiles.
Article
Chemistry, Multidisciplinary
Elwira Bisz, Martina Koston, Michal Szostak
Summary: A new study reported the use of non-toxic and sustainable N-butylpyrrolidone (NBP) as a substitute for reprotoxic N-methylpyrrolidone (NMP) in iron-catalyzed cross-coupling reactions, achieving successful alkylations with high efficiency and broad functional group tolerance. The efficiency of NBP in these reactions surpassed or matched that of NMP, demonstrating potential applications in the synthesis of pharmaceutical intermediates.
Article
Chemistry, Organic
Jihye Kim, Jieun Jang, Yoonho Lee, Kwangmin Shin
Summary: In this study, a nickel hydride-catalyzed hydroacylation of aryl alkenes using aroyl fluorides was reported. The reaction proceeds without the need for an exogenous ligand, and the synthetic utility of the method was demonstrated.
Review
Chemistry, Multidisciplinary
Ewa Pietrasiak, Eunsung Lee
Summary: Examples of Grignard reagents obtained by C-F bond activation with magnesium have been widely reported in the literature over the past century. Efforts have been made to prepare highly active forms of magnesium due to the high bond dissociation energy of the C-F bond. Modern approaches involve the use of Mg(i)-Mg(i) dimers and transition metal catalysts for C-F bond activation, followed by transmetallation with a magnesium salt.
CHEMICAL COMMUNICATIONS
(2022)
Article
Chemistry, Analytical
Pinky Chowdhury, Byung Seok Cha, Seokjoon Kim, Eun Sung Lee, Taehwi Yoon, Jisu Woo, Ki Soo Park
Summary: In this study, a simple electrochemical biosensor was developed for the specific detection of KRAS gene mutation using the differential pulse voltammetry technique. The biosensor utilizes the mismatch-specific cleavage activity of T7E1 enzyme coupled with horseradish peroxidase to catalyze the oxidation reaction, enabling the detection of mutant genes. The use of a nanocomposite further enhances the electrochemical signal. The biosensor shows potential for the detection of mutations in early disease diagnosis.
Article
Chemistry, Analytical
Seokhwan Kim, Jung Ho Kim, Seokjoon Kim, Jung Soo Park, Byung Seok Cha, Eun Sung Lee, Jinjoo Han, Jiye Shin, Youngjun Jang, Ki Soo Park
Summary: A loop-mediated isothermal amplification-based nucleic acid lateral flow assay (LAMP-NALFA) system was developed for specific and multiplex detection of genetic markers at a low cost. The system demonstrated high selectivity in discriminating target amplification products and non-specific amplification products, and showed good practical applicability in different samples.
ANALYTICA CHIMICA ACTA
(2022)
Article
Chemistry, Analytical
Ayemeh Bagheri Hashkavayi, Byung Seok Cha, Eun Sung Lee, Ki Soo Park
Summary: Breast cancer is a leading cause of cancer-related death, and an effective diagnostic system for early cancer detection is required. In this study, an ultrasensitive electrochemical aptasensor based on metal ion signals was developed for the multiplex detection of exosome biomarkers. The sensor can simultaneously and specifically detect EpCAM and HER-2 positive exosomes with a low detection limit.
ANALYTICA CHIMICA ACTA
(2022)
Article
Chemistry, Analytical
Seokjoon Kim, Jinjoo Han, Jung Soo Park, Jung Ho Kim, Eun Sung Lee, Byung Seok Cha, Ki Soo Park
Summary: This study proposes a novel method for the accurate and non-invasive diagnosis of CRC based on the analysis of exosomes using a DNA barcode-based nucleic acid lateral flow assay. The proposed assay successfully detected overexpressed miRNAs in CRC exosomes and achieved high analytical performance with a sensitivity and specificity of 95.24% and 100.0%, respectively. This method can serve as a simple diagnostic platform for the detection of exosomal miRNA.
Article
Chemistry, Multidisciplinary
Hayoung Song, Eunsung Lee
Summary: Despite a recent proposal on the mechanism of a single-electron transfer (SET) process between tritylium and 2,6-bis(diisopropylphenyl)imidazol-2-ylidene (IPr) based on evidence of transient IPr radical cation intermediate ([IPr]·+) formation, such oxidation is still contentious because of the high oxidation potential of N-heterocyclic carbenes. Our experimental analysis indicates that the appearance of deep purple color, previously considered to be from transient [IPr]·+, originates from a zwitterionic intermediate (3 a), not a radical cation. Here, we propose an alternative mechanism for the reaction involving tritylium and IPr.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Physical
Cong-Xue Liu, Dong-Lai Pan, Younggyu Seo, Seungjae Park, Jing -Lan Kan, Jin Young Koo, Wonyong Choi, Eunsung Lee
Summary: The first examples of phenanthroimidazole-based covalent organic frameworks (COFs), PIm-COF1 and PIm-COF2, were reported in this study, showing substantial optical properties. PIm-COF2 exhibited an average hydrogen evolution rate of 7417.5 μmolg-1h-1, which was 14 times higher than that of PIm-COF1 (528.5 μmolg-1h-1). This can be attributed to the strong donor-acceptor effect of PIm-COF2 and the continuous separation and transfer of the photoexcited electron-hole pair from the phenanthro[9,10-d]imidazole moiety, which was confirmed by time-dependent density functional theory and excitation state analysis.
ACS APPLIED ENERGY MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Yongbeom Shin, Myeongnam Park, Jaewook Lee, Kibyung Kang, Sungki Wang, Eunsung Lee, Seongkeun Song, Dongil Shin
Summary: Using a combination of multiple linear regression (MLR) model and GRU model with real process operating data, a method for long-term stable operation and optimization of continuous concurrent catalytic reforming process is proposed. The model predicts the performance degradation and lifetime of the catalyst, and defines a new variable, catalyst activity, to predict the future reformate yield. Based on the predicted catalyst lifetime and different operating conditions, an appropriate production plan of the reformate oil can be established.
KOREAN JOURNAL OF CHEMICAL ENGINEERING
(2023)
Article
Chemistry, Organic
Solhye Choe, Hayoung Song, Hyeonjeong Choi, Seunghyuk Yoo, Jaelim Kim, Young Ho Ko, Eunsung Lee
Summary: Two air-stable organic radicals were synthesized from oxalyl chloride and cAAC, leading to the unexpected formation of a known radical cation with amino and carboxy groups, as well as the oxidative formation of a 1,2-dicarbonyl radical cation from a neutral 3-oxetanone compound. The newly discovered compound 4, highly strained, was obtained by single-electron reduction of a [3]BF4 with a mild reducing agent, indicating the uniqueness of cAAC compared to NHC-based radicals.
Article
Chemistry, Inorganic & Nuclear
Seung Yeon Jeong, Jaelim Kim, Eunsung Lee, Kyung-sun Son
Summary: A new chromium(III) complex (2) with an aminotriphenolate ligand (LtBu,tBu) was developed as an efficient catalyst for ring-opening copolymerization to produce polyesters. The crystal structure of complex 2 showed an octahedral geometry despite the steric hindrance of LtBu,tBu. After optimizing the reaction conditions, complex 2 with a cocatalyst produced perfectly alternating polyesters with high molecular weights and low dispersity. Furthermore, the polyesters prepared using different comonomers exhibited relatively high glass transition temperatures.
Article
Biochemistry & Molecular Biology
Young Jun Jang, Byung Seok Cha, Doyeon Kim, Eun Sung Lee, Seokjoon Kim, Jinjoo Han, Jiye Shin, Seokhwan Kim, Ki Soo Park
Summary: This study proposes a new strategy to enhance the biological activities of astaxanthin (AST) using fetal bovine serum-derived extracellular vesicles (EVs). AST-incorporated EVs (EV-ASTs) showed high stability and maintained their original EV morphology, resulting in excellent antioxidant and anti-inflammatory activities in various cells. The mechanism behind the enhanced biological activities of EV-ASTs was also investigated. These findings provide insights into improving the performance of hydrophobic drugs using nature-derived EVs and contribute to the development of novel drug-delivery systems.
Article
Chemistry, Analytical
Daehan Nam, Seokjoon Kim, Jung Ho Kim, Seungjin Lee, Daneub Kim, Jinseo Son, Doyeon Kim, Byung Seok Cha, Eun Sung Lee, Ki Soo Park
Summary: Loop-mediated isothermal amplification (LAMP) is a widely used molecular diagnostics technology. This study introduces a new version of LAMP, called low-temperature LAMP, which operates at 37 degrees C for on-site diagnosis. The low-temperature LAMP differs from conventional LAMP in terms of MgSO4 and dNTPs concentrations, as well as the lengths of DNA probes. Under optimal conditions, low-temperature LAMP shows comparable amplification efficiency to conventional LAMP. Additionally, the method enables the detection of miR-21 with high sensitivity and selectivity at 37 degrees C, without requiring expensive DNA modifications or special additives.
Editorial Material
Chemistry, Multidisciplinary
Hayoung Song, Eunsung Lee
TRENDS IN CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Junbeom Park, Jaelim Kim, Gu Yoon Jeong, Youngsuk Kim, Eunsung Lee
Summary: This study investigates the electron and proton transfer chemistry of N-heterocyclic carbene nitric oxide radical compounds and prepares a variety of nitrosyl derivatives. The reactions of these derivatives resemble those of transition metal nitrosyl complexes.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Engineering, Aerospace
Jae-Hyuk Lee, Jae-Hoon Ryu, Eun-Sung Lee, Hyung-Seok Han, Jeong-Yeol Choi
Summary: A noncircular RDE with a tri-arc shaped cross-section was constructed and tested, showing slightly better stability and propulsion performance than an ordinary circular-shaped RDE. The repeated curvature changes in the tri-arc design positively affected the stability of detonation wave propagation.
