Article
Chemistry, Multidisciplinary
Xun Zhang, Chengjian Zhang, Xinghong Zhang
Summary: The alternating copolymerization of cyclic acetals and anhydrides can produce biodegradable polyesters with high oxygen content, moderate molecular weight, and narrow polydispersities.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Kaitlin R. Albanese, Parker T. Morris, Javier Read de Alaniz, Christopher M. Bates, Craig J. Hawker
Summary: This study presents the synthesis and characterization of statistical and block copolymers containing alpha-lipoic acid (LA) using reversible addition-fragmentation chain-transfer (RAFT) polymerization. The controlled copolymerization of LA and vinyl monomers allows for the synthesis of copolymers with predictable molecular weights and low molar-mass dispersities. The presence of lipoic acid diads in the resulting copolymers, which include disulfide bonds, enables efficient degradation when exposed to mild reducing agents.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Organic
Ziyi Zhang, Jin Wang, Shenghai Guo, Jing Fan, Xuesen Fan
Summary: We report an efficient strategy for preparing 5H-phthalazino[1,2-b]quinazolin-8(6H)-one derivatives through a t-BuOK-catalyzed intramolecular hydroamination reaction of functionalized quinazolinones. The reaction proceeds under mild conditions and yields the desired products in good to high yields via exclusive 6-exo-dig cyclization. This protocol offers readily available starting materials, broad substrate scope, and high regio- and stereoselectivity.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Biochemistry & Molecular Biology
Boriss Strumfs, Jekaterina Hermane, Sergey Belyakov, Artjoms Sobolevs, Kirils Velikijs, Romans Uljanovs, Peteris Trapencieris, Ilze Strumfa
Summary: The reaction of N,N-Dimethylaziridine-2-carboxamides with organolithium reagents yields 2-aziridinylketones, which can further react to form symmetrical and unsymmetrical aziridinyl carbinols. The use of excess phenyllithium can serve as a unique N-Boc protecting group cleavage method for acid-sensitive substrates.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2021)
Article
Chemistry, Organic
Kosuke Ohsawa, Junya Kubota, Shota Ochiai, Takayuki Doi
Summary: The stereoselective and short-step synthesis of N-protected allo-carnosadine, ent-carnosadine, and carnosadine lactam was achieved from a common cyclopropane intermediate. The key cyclopropane was obtained in excellent yield and optical purity through an inter-intramolecular double alkylation reaction. Subsequent monohydrolysis of the diester moiety under different reaction conditions provided diastereomers of monoacids, which were further converted to three carnosadine derivatives in 5-6 steps from the common diester.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Biochemistry & Molecular Biology
Pawel A. Wieczorkiewicz, Tadeusz M. Krygowski, Halina Szatylowicz
Summary: The study investigated the influence of solvents on intramolecular interactions in 5- or 6-substituted nitro and amino derivatives of six tautomeric forms of uracil using density functional theory calculations. It was found that the properties of substituents were enhanced in polar solvents, depending on the ortho interactions. Substitution or solvation did not significantly change tautomeric preferences of uracil, but the formation of a strong intramolecular hydrogen bond in the 5-NO2 derivative stabilized the dienol tautomer.
Article
Chemistry, Organic
Eliott Le Du, Julien Borrel, Jerome Waser
Summary: In this study, a copper-catalyzed alkynylation of azadipeptides using ethynylbenziodoxolone (EBX) reagents was reported. Nonsymmetrical ynehydrazides could be obtained in high yields using azaglycine derivatives as nucleophiles. The reaction is compatible with various functional groups naturally occurring on amino acid side chains and allows the transfer of different substituents. The obtained products can be further functionalized.
Article
Chemistry, Organic
Yuting Qiu, Haiyan Yuan, Xiaoying Zhang, Jingping Zhang
Summary: Computational studies of CPA-catalyzed DyKAH reactions reveal a catalytic asymmetric model involving pi-allylic carbocationic intermediates, with high E/Z selectivity achieved through intermolecular proton transfer. Noncovalent interactions within the electrostatic environment created by the phosphoric acid are key to explaining the enantioselectivity, while the chiral SPINOL scaffolds control the signs of enantioselectivity through substrate binding pocket configurations. Overall, understanding these mechanisms is crucial for guiding DyKAH reactions.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Physical
Dandan Yang, Hai Huang, He Zhang, Li-Ming Yin, Mao-Ping Song, Jun-Long Niu
Summary: The study achieved the Co-H-catalyzed intermolecular hydroamination of unactivated alkenes with various amine electrophiles by introducing a removable directing group. The catalytic system showed substrate-dependent regioselectivity, broad substrate scope, and simplified reaction conditions, providing a general and flexible protocol for the preparation of various amino acid derivatives.
Article
Chemistry, Multidisciplinary
Christian L. L. Jankovic, Kyle C. C. McIntosh, Verner A. A. Lofstrand, F. G. West
Summary: Mild fluoride-mediated desilylative conditions generate 1,2-cyclohexadienes, which undergo efficient intramolecular [2+2] trapping to form tricyclic alkylidene cyclobutanes with complete diastereoselectivity for the cis-fused products. These cyclohexadienes can be trapped by pendent styrenes or electron-deficient olefins, and 14 substrates have been disclosed. The reactions achieve yields up to 91% at ambient temperature using only cesium fluoride and the necessary precursors are easily accessible from substituted 2-bromocyclohexenones.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Mario Martinez-Mingo, Andres Garcia-Viada, Daniel Sowa Prendes, Ines Alonso, Nuria Rodriguez, Ramon Gomez Arrayas, Juan C. Carretero
Summary: The selective delta-C(sp(3))-H acetoxylation of N-(SO2Py)-protected amino acid derivatives has been achieved using palladium-catalysis and PhI(OAc)(2) as both oxidant and acetoxy source. The unique structural and electronic features of SO2Py are crucial in overriding the more favorable intramolecular C-H amination.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Zeguo Fang, Lin Xie, Liang Wang, Qian Zhang, Dong Li
Summary: A synthesis method for gamma-lactam-substituted quinone derivatives has been developed through a cascade cyclization and functionalization reaction catalyzed by Ag2O. Related 2-oxazolidinone substituted quinone products can also be obtained using N-aryl allyl carbamates. The reactions proceed via an amidyl radical-initiated cyclization and subsequent radical addition to quinones. This provides an efficient route to various gamma-lactam-substituted quinone derivatives with a wide range of substrate scope.
Article
Chemistry, Inorganic & Nuclear
Emily Y. Fok, Veronica L. Show, Adam R. Johnson
Summary: The laboratory has developed catalysts based on earth abundant titanium for asymmetric reactions, showing improved enantioselectivity with new ligands, but unexpected dimerization of the catalyst resulted in reduced activity.
Article
Chemistry, Multidisciplinary
Yunnan Xu, Delong Liu, Yu Deng, Yi Zhou, Wanbin Zhang
Summary: An asymmetric hydrogenation of 3-benzoylaminocoumarins was achieved for the first time using the BridgePhos-Rh catalytic system, providing chiral 3-amino dihydrocoumarins in high yields and with excellent enantioselectivities. The relationship between the enantioselectivities of the hydrogenations and the dihedral angles and the resulting pi-pi stacking effects of the BridgePhos-Rh complexes, determined by X-ray diffraction analysis, was discussed. The corresponding hydrogenated products allow for many transformations, providing several chiral skeletons with important physiological and pharmacological activities.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Medicinal
Dongjae Lee, Sungjin Lee, Jieun Choi, Yoo-Kyung Song, Min Ju Kim, Dae-Seop Shin, Myung Ae Bae, Yong-Chul Kim, Chin-Ju Park, Kyeong-Ryoon Lee, Jun-Ho Choi, Jiwon Seo
Summary: The study reveals that CsO exhibits lower chameleonic behavior in conformation, resulting in decreased membrane permeability, but its more rigid conformation does not have a negative impact on the pharmacokinetic profile. CsO shows higher plasma concentration than CsA due to its minimal CypA binding and lower accumulation in red blood cells.
JOURNAL OF MEDICINAL CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Zhong-Wei Hou, Ding-Jin Liu, Peng Xiong, Xiao-Li Lai, Jinshuai Song, Hai-Chao Xu
Summary: This study reports a site-selective electrochemical amination reaction that can convert benzylic C-H bonds into C-N linkages without the need for external oxidants or metal catalysts. The success lies in using HFIP as a co-solvent to modulate the oxidation potentials of the substrate and product, avoiding overoxidation of the latter.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Applied
Hong Yan, Shaobin Zhu, Hai-Chao Xu
Summary: A two-step continuous-flow system was developed for the synthesis of functionalized acridinium photocatalysts through late-stage C(aryl)-H functionalization of the acridinium core, allowing the introduction of a diverse range of alkyl groups and formation of 3,6-disubstituted acridinium dyes.
ORGANIC PROCESS RESEARCH & DEVELOPMENT
(2021)
Review
Chemistry, Multidisciplinary
Na Chen, Hai-Chao Xu
Summary: Organic radicals, versatile synthetic intermediates with complementary reactivities to ionic species, have limited scope in electrochemically driven reactions; however, research activity in organic electrochemistry has significantly increased in recent years, with the development of methods for generating and utilizing organic radicals for synthesis through direct electrolysis, molecular electrocatalysis, or molecular electrophotocatalysis.
Article
Electrochemistry
Zhong-Wei Hou, Hai-Chao Xu
Summary: An electrophotocatalytic method has been developed for the dehydrogenative cross coupling of arenes with azoles using a bicatalytic system consisting of acridinium dye and (2,2,6,6-tetramethylpiperidin-1-yl)oxyl (TEMPO). The reactions take place in a simple undivided cell with visible-light irradiation and do not require an external chemical oxidant.
Article
Chemistry, Organic
Yun-Tao Zheng, Jinshuai Song, Hai-Chao Xu
Summary: Indole is commonly found in bioactive compounds and natural products. A new electrocatalytic method has been developed for the synthesis of indoles through dehydrogenative cyclization of 2-vinylanilides, providing a speedy and efficient access to 3-substituted and 2,3-disubstituted indoles without the need for external chemical oxidants.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Multidisciplinary Sciences
Chen-Yan Cai, Zheng-Jian Wu, Ji-Ying Liu, Ming Chen, Jinshuai Song, Hai-Chao Xu
Summary: Oxidative allylic C-H functionalization is a powerful tool in organic synthesis, minimizing the need for functional group activation and generating alkenyl-substituted products amenable to further modifications. The authors introduce an oxidant-free, electrocatalytic approach using tailored cobalt-salen complexes for intramolecular oxidative allylic C-H amination and alkylation, broadening the scope of such reactions.
NATURE COMMUNICATIONS
(2021)
Article
Chemistry, Multidisciplinary
Ming Chen, Zheng-Jian Wu, Jinshuai Song, Hai-Chao Xu
Summary: In this study, an electrocatalytic allylic C-H alkylation reaction with carbon nucleophiles was achieved using a readily available cobalt-salen complex as the catalyst. The mild conditions and unique electrocatalytic radical process allowed for excellent functional group tolerance and substrate compatibility.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Organic
Bin Guo, Hai-Chao Xu
Summary: The electrocatalytic dehydrogenative C(sp3)-H/C(sp)-H cross-coupling of tetrahydroisoquinolines with terminal alkynes has been achieved in a continuous-flow microreactor using TEMPO/copper relay catalysis. The reaction is easily scalable, requires low concentration of supporting electrolyte, and does not need external chemical oxidants or ligands, providing a straightforward and sustainable access to 2-functionalized tetrahydroisoquinolines.
BEILSTEIN JOURNAL OF ORGANIC CHEMISTRY
(2021)
Review
Chemistry, Multidisciplinary
Ya-Long Liu, Xiang-Yue Liu, Li Feng, Lan-Xing Shao, Si-Jun Li, Jing Tang, Hu Cheng, Zhuo Chen, Rui Huang, Hai-Chao Xu, Jin-Liang Zhuang
Summary: Two-dimensional metal-organic nanosheets (2D MONs) are emerging ultrathin, porous, and crystalline materials with advantages such as diversity of organic ligands and metal nodes. They possess high density and accessible catalytic sites, reducing diffusion pathways and enabling fast electron transport. This review summarizes the synthetic methods for fabricating 2D MONs, discusses their applications in electrocatalysis and photocatalysis, and provides insights into future design and synthesis challenges for high-performance applications.
Editorial Material
Chemistry, Organic
Hai-Chao Xu, Kevin D. Moeller
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Liang-Hua Jie, Bin Guo, Jinshuai Song, Hai-Chao Xu
Summary: This study presents an electrocatalytic strategy for the cyclopropanation of active methylene compounds using an organic catalyst, which eliminates the need for transition metal catalysts and external chemical oxidants. The method shows a broad substrate scope and excellent scalability, allowing for the convenient synthesis of various types of cyclopropane-fused heterocyclic and carbocyclic compounds.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Multidisciplinary Sciences
Hao Long, Chong Huang, Yun-Tao Zheng, Zhao-Yu Li, Liang-Hua Jie, Jinshuai Song, Shaobin Zhu, Hai-Chao Xu
Summary: The study presents a catalyst- and external oxidant-free continuous flow electrochemical C-H phosphorylation reaction for synthesizing aryl phosphorus compounds. The reaction involves arenes reacting with anodically generated P-radical cations, allowing for efficient reactions of arenes with diverse electronic properties and selective late-stage functionalization of complex natural products and bioactive compounds. The method demonstrates the synthetic utility by producing 55.0 grams of phosphonate product in a continuous manner.
NATURE COMMUNICATIONS
(2021)
Article
Multidisciplinary Sciences
Hao Long, Tian-Sheng Chen, Jinshuai Song, Shaobin Zhu, Hai-Chao Xu
Summary: The authors report a scalable electrochemical method for the direct hydroxylation of arene C-H bonds in continuous flow, resulting in the synthesis of phenols. This method does not require any catalysts or chemical oxidants, and exhibits excellent selectivity and efficiency, making it applicable to a wide range of arenes. The authors demonstrate the scalability of this method by continuously producing a significant amount of phenol product.
NATURE COMMUNICATIONS
(2022)
Review
Chemistry, Physical
Zhong-Wei Hou, Hai-Chao Xu, Lei Wang
Summary: This review summarizes the recent advances in electrochemical dehydrogenative N-H/N-H coupling reactions, focusing on the mechanistic insights and synthetic applications of these transformations.
CURRENT OPINION IN ELECTROCHEMISTRY
(2022)
Article
Chemistry, Organic
Zhong-Wei Hou, Zhong-Yi Mao, Hai-Chao Xu
Summary: In this study, tris(4-(tert-butyl)phenyl)amine was unexpectedly found to decompose into a tetraarylhydrazine during electrolysis, which can be used as an electrocatalyst for the synthesis of N-heteroaromatic compounds without the need for external chemical oxidants. This metal-free electrocatalytic method provides a straightforward access to N-heteroaromatic compounds from readily available materials.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2021)
