Article
Chemistry, Organic
Zhi-Yong Ma, Mengyang Li, Li-Na Guo, Le Liu, Dongdong Wang, Xin-Hua Duan
Summary: The sulfonamide was investigated as a hydrogen-atom transfer catalyst for C(sp(3))-H alkylation based on DFT calculations, showing high regioselectivity and broad substrate scope. Additionally, the sulfonamide catalyst was also found to be applicable for C(sp(3))-C(sp(3) couplings through a combination of photoredox, nickel, and HAT catalysis.
Article
Chemistry, Applied
Yi-Ting Wang, Yi-Lun Shih, Yen-Ku Wu, Ilhyong Ryu
Summary: Site-selective C(sp(3))-H alkenylation was achieved under photo-irradiation in the presence of a catalytic decatungstate anion. The reaction successfully combines radical addition/beta-scission sequence with photocatalytic C(sp(3))-H functionalization. The decatungstate anion participates in a chain-repairing step in reactions with weaker C-H bonds.
ADVANCED SYNTHESIS & CATALYSIS
(2022)
Article
Chemistry, Multidisciplinary
Sergio Sisti, Marco Galeotti, Filippo Scarchilli, Michela Salamone, Miquel Costas, Massimo Bietti
Summary: A detailed study on C(sp(3))-H bond oxygenation reactions catalyzed by [Mn(OTf)(2)((TIPS)mcp)] complex was conducted, showing that the introduction of electron-withdrawing functional groups in different solvents significantly increased site-selectivity and product yield. The study also achieved selective control over multiple methylenic sites.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Geunho Choi, Geun Seok Lee, Beomsoon Park, Dongwook Kim, Soon Hyeok Hong
Summary: A mild and operationally simple C(sp(3))-H trifluoromethylation method has been developed for unactivated alkanes using a bench-stable Cu-III complex as the initiator of the visible-light photoinduced reaction, as well as a source of trifluoromethyl radicals and trifluoromethyl anions for functionalization. The methylene-selective reaction mechanism involves radical-polar crossover and ionic coupling between the reactive carbocation intermediate and the anionic CF3 source, enabling efficient C-CF3 bond formation. This method can be applied for late-stage trifluoromethylation of natural products and bioactive molecules.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Organic
Anupam Kumar Singh, Jogendra Kumar, Sukalyan Bhadra
Summary: An elegant and catalytic procedure for the one-step cyanomethylenation of C(sp(3))-H bonds adjacent to benzazoles and ketones is described. The method involves using DMF as a C-1 unit and TMSCN as the cyanide source, and the copper-mediated reaction between DMF and TMSCN produces a cyanomethylene radical intermediate. This intermediate reacts with 2-alkylbenzazoles or alkylketones under palladium catalysis to yield the desired cyanomethylenated compounds. The subsequent interconversion of the cyanomethylenated products enhances the synthetic attractiveness of the protocol.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Liming Yang, Henan Xie, Guanghui An, Guangming Li
Summary: In this study, a new method was developed to enhance the coordination of Pd catalysts with weak-coordinating substrates using a commercially available sulfonic acid, enabling arylation and alkenylation of C(sp(3))-H bonds of Weinreb amides.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Fang Wang, Jiaming Chen, Xiaoqi Jia, Dailin Zhuang, Zhenyang Wan, Lifang Ma, Ziyuan Li
Summary: A remote directing group-enabled radical relay strategy for benzylic direct C(sp3)-H alkoxylation with alcohols at room temperature is developed, which achieves satisfactory site-selectivity, chemoselectivity, and reaction scope under simple and mild conditions without the need for ligands or additives.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Physical
Charles B. Musgrave, Kaeleigh Olsen, Nichole S. Liebov, John T. Groves, William A. Goddard, T. Brent Gunnoe
Summary: The decatungstate anion (DT) is a useful photocatalyst for C-H functionalization in organic transformations. We demonstrate the photochemical partial oxidation of methane to methyl trifluoroacetate using DT as a catalyst. The proposed mechanism involves synergistic relationships among DT, chloride, and iodine species to achieve efficient aerobic methane partial oxidation.
Article
Chemistry, Multidisciplinary
Patrick J. Sarver, Noah B. Bissonnette, David W. C. MacMillan
Summary: The study presents a method for converting strong, aliphatic C(sp(3))-H bonds into alkyl sulfinic acids using decatungstate photocatalysis, which can be applied to a variety of C(sp(3))-rich molecules for efficient synthesis of complex sulfur-containing compounds. Furthermore, the method demonstrates potential for divergent synthesis of pharmaceutically relevant molecules through diversification of the sulfinic acid products into various medicinally relevant functional groups.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Organic
Xiaosa Lu, Yinhua Huang
Summary: A new method for the stereospecific cyanation of olefinic C-H bonds using rhodium catalysis has been developed, resulting in the synthesis of beta,beta-disubstituted acrylonitriles under mild conditions. This approach does not require directing groups, tolerates various functional groups, and provides a concise and green access to a wide range of disubstituted acrylonitriles in good to excellent yields.
ORGANIC CHEMISTRY FRONTIERS
(2021)
Article
Chemistry, Multidisciplinary
Ting Wan, Zhenghui Wen, Gabriele Laudadio, Luca Capaldo, Rob Lammers, Juan A. Rincon, Pablo Garcia-Losada, Carlos Mateos, Michael O. Frederick, Remy Broersma, Timothy Noel
Summary: This study demonstrates the successful regioselective and scalable C(sp(3))-H amination via decatungstate photocatalysis using a newly developed high-intensity LED photoreactor. The platform enables fast results gathering and bridges the gap between academic discovery and industrial production.
ACS CENTRAL SCIENCE
(2022)
Article
Chemistry, Multidisciplinary
Liang Hu, Guangrong Meng, Jin-Quan Yu
Summary: This study reports the first Pd(II)-catalyzed intermolecular fi-methylene C(sp3)-H arylation of free aliphatic acids using bidentate pyridine-pyridone ligands. The bite angle of the ligand plays a key role in promoting fi-methylene C-H activation of free carboxylic acid. This transformation provides a disconnection for alkylation of arenes with simple aliphatic acids.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Multidisciplinary
Hediyala B. Chandrashekar, Pravas Dolui, Bijin Li, Astam Mandal, Hao Liu, Srimanta Guin, Haibo Ge, Debabrata Maiti
Summary: In this study, oxidative borylation at the distal delta-position of aliphatic amines was achieved using various borylating agents, a palladium catalyst, and a properly tuned ligand in the presence of a cheap oxidant. Furthermore, an organopalladium delta-C(sp(3))-H-activated intermediate was isolated and crystallographically characterized to gain mechanistic insight.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Multidisciplinary Sciences
Yujun Li, Shaopeng Guo, Qing-Han Li, Ke Zheng
Summary: This paper presents a mild, metal-free method for constructing alpha-tertiary amino acids (ATAAs) using the cross-dehydrogenative coupling (CDC) reaction. The method exhibits excellent functional group tolerance and late-stage applicability, and allows for the synthesis of ATAAs under mild conditions.
NATURE COMMUNICATIONS
(2023)
Article
Chemistry, Physical
Zhihao Wang, Jian Li, Yumiao Liu, Qing Chen, Pengfei Zhang, Jirong Wu
Summary: An effective strategy for the direct α- C (sp3)-H thioetheration/selenylation of nafimidone derivatives has been introduced using electrocatalysis. A wide range of nafimidone, disulfide, and diselenide derivatives showed good compatibility and yielded corresponding products in moderate to good yields. Control experiments indicated that the reaction proceeds through a radical mechanism. This methodology not only offers a new approach for C(sp3)-H bond activation but also expands the scope of potential biological activity in nafimidone derivatives.
MOLECULAR CATALYSIS
(2023)
Article
Chemistry, Multidisciplinary
Geunho Choi, Geun Seok Lee, Beomsoon Park, Dongwook Kim, Soon Hyeok Hong
Summary: A mild and operationally simple C(sp(3))-H trifluoromethylation method has been developed for unactivated alkanes using a bench-stable Cu-III complex as the initiator of the visible-light photoinduced reaction, as well as a source of trifluoromethyl radicals and trifluoromethyl anions for functionalization. The methylene-selective reaction mechanism involves radical-polar crossover and ionic coupling between the reactive carbocation intermediate and the anionic CF3 source, enabling efficient C-CF3 bond formation. This method can be applied for late-stage trifluoromethylation of natural products and bioactive molecules.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Multidisciplinary Sciences
Geun Seok Lee, Daeun Kim, Soon Hyeok Hong
Summary: The use of alkyl chlorides in Pd-catalyzed Mizoroki-Heck coupling reactions remains a challenging issue due to the high thermodynamic barrier of alkyl chloride activation and the propensity of alkylpalladium complexes to undergo undesired beta-hydride elimination. However, this study demonstrates that alkyl chlorides, including tertiary ones, can efficiently participate in Mizoroki-Heck cross-coupling reactions under mild conditions via photoinduced Pd catalysis, offering great potential for late-stage functionalizations and molecular complexity.
NATURE COMMUNICATIONS
(2021)
Article
Chemistry, Multidisciplinary
Jeonghyo Lee, Seongho Jin, Dongwook Kim, Soon Hyeok Hong, Sukbok Chang
Summary: Alkanes, as an abundant and inexpensive source of hydrocarbons, are of high interest for conversion into value-added chemicals. Development of new methods for this transformation is challenging due to the inertness of C-H bonds. Electronic modulation of cobalt complexes has led to enhanced amidation efficiency, with secondary C-H bond selectivity observed in nonactivated alkanes under the current protocol.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Applied
Seulchan Lee, Ju-Hyung Chae, Yongmoon Yang, In-Hwan Lee, Hye-Young Jang
Summary: Thermal properties of polyketones can be engineered by varying the styrene content in terpolymers derived from ethylene, styrene, and CO sources. Palladium catalysts modified with iminopyridine ligands play key roles in polymerization reactions by showing distinct steric and electronic effects.
APPLIED ORGANOMETALLIC CHEMISTRY
(2021)
Article
Chemistry, Applied
Sehye Min, Beomsoon Park, Jantakan Nedsaengtip, Soon Hyeok Hong
Summary: The mechanochemical fluorination of unactivated C(sp(3))-H bonds has been achieved using N-fluorobenzenesulfonimide as both a precursor of the hydrogen-atom-transfer reagent and a bench-stable fluorine source. Control experiments have confirmed the essential role of mechanical energy in this reaction.
ADVANCED SYNTHESIS & CATALYSIS
(2022)
Article
Polymer Science
Hyunwoo Park, Jaeho Lee, Soon-Hyeok Hwang, Daeun Kim, Soon Hyeok Hong, Tae-Lim Choi
Summary: By modulating boronates, the rate of the Suzuki-Miyaura CTP (SCTP) reaction can be controlled, achieving precision synthesis of polymers.
Article
Chemistry, Physical
Seok-Hyeon Cheong, Daeun Kim, Huyen Tran Dang, Dongwook Kim, Bora Seo, Minserk Cheong, Soon Hyeok Hong, Hyunjoo Lee
Summary: This study reports that the anionic form of palladium, PdCl(4)(2-), can effectively convert methane to methyl trifluoroacetate (MeTFA) in the K2S2O8-HTFA oxidation system. The anionic catalyst form increases Pd solubility in the HTFA solvent, facilitating the conversion to the real catalytic species. The role of trifluoroacetic anhydride (TFAA) in removing water produced by the oxidant and oxidation byproduct is also identified for the first time.
JOURNAL OF CATALYSIS
(2022)
Article
Multidisciplinary Sciences
Geun Seok Lee, Beomsoon Park, Soon Hyeok Hong
Summary: In this study, an efficient method for the stereoretentive direct cross-coupling of chiral amino acid chlorides and unactivated C(sp(3))-H hydrocarbons was achieved via photoredox catalysis. The strategic generation of an N-acyllutidinium intermediate facilitated the synthesis of chiral amino ketones with retention of stereochemistry.
NATURE COMMUNICATIONS
(2022)
Article
Chemistry, Organic
Seoksun Kim, Beomsoon Park, Geun Seok Lee, Soon Hyeok Hong
Summary: In this study, the photocatalytic synthesis of alpha-aminoacetals via decarboxylative coupling of imine and 2,2-diethoxyacetic acid was achieved using a nonstoichiometric amount of a radical initiator. Various functional groups were compatible, providing efficient one-step access to diversely functionalized alpha-aminoacetals, which shows great potential for further research.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Review
Chemistry, Multidisciplinary
Jungwon Kim, Soon Hyeok Hong
Summary: Isocyanides are widely used in organic synthesis to construct valuable chemical structures. The classical Ugi 4-component reaction is a robust method for synthesizing diversely functionalized peptoids. Various nitrogen heterocycles have been efficiently synthesized from commercially available compounds using established cyclization techniques. Transition metal-catalyzed processes and recently developed synthetic methods have enhanced the efficiency, availability, and novelty of isocyanide chemistry.
BULLETIN OF THE KOREAN CHEMICAL SOCIETY
(2023)
Review
Chemistry, Multidisciplinary
Geun Seok Lee, Soon Hyeok Hong
Summary: Synthetic chemists have been striving to develop efficient methods for synthesizing ketones, which are important building blocks in organic chemistry and have significant roles in bioactive molecules. Recent research has focused on using photoredox catalysis to synthesize ketones through the cross-coupling of an acyl electrophile and C(sp(3))-H bonds. By optimizing reaction conditions, studying substrate scope, and investigating reaction mechanisms, a versatile method for directly acylating activated hydrocarbons to forge ketones has been developed. This method has a rating of 9 out of 10 in terms of its importance.
ACCOUNTS OF CHEMICAL RESEARCH
(2023)
Article
Chemistry, Multidisciplinary
Jungwon Kim, Siin Kim, Geunho Choi, Geun Seok Lee, Donghyeok Kim, Jungkweon Choi, Hyotcherl Ihee, Soon Hyeok Hong
Summary: This study successfully achieved the visible-light-induced photocatalytic synthesis of N-aryl amines by implementing a unique strategy for controlled dehydrogenation of amines. This approach using C6F5I as a hydrogen-atom acceptor allowed for the mild and controlled dehydrogenation of amines with various functional groups and activated C-H bonds, while preventing side reactions of the reactive N-aryl amine products. Thorough mechanistic studies revealed the involvement of single-electron and hydrogen-atom transfers in a specific order to synergistically control reactivity. Notably, the back-electron transfer process played a key role in preventing further reactions of the desired product under oxidative conditions.
