Article
Chemistry, Organic
Tatsuhiro Uchikura, Kureha Aruga, Riku Suzuki, Takahiko Akiyama
Summary: In this study, an enantioselective Friedel-Crafts alkylation reaction was developed using chiral phosphoric acid as the catalyst to react N-unprotected alkynyl trifluoromethyl ketimines with pyrroles, resulting in the synthesis of chiral primary alpha-trifluoromethyl-alpha-(2-pyrrolyl)propargyl-amines with high enantioselectivity. The alkynyl group of the adducts can be transformed without a loss of optical purity, leading to optically active alpha-trifluoromethylated amines bearing various substituents.
Article
Chemistry, Multidisciplinary
Chenguang Liu, Mingyang Wang, Yihan Xu, Yibiao Li, Qiang Liu
Summary: This study presents a Mn-catalyzed asymmetric hydrogenation of 3H-indoles, achieving high yields and enantioselectivities. The use of manganese catalyst allows for the compatibility of acid-sensitive functional groups, expanding the scope of this transformation and highlighting the uniqueness of earth-abundant metal catalysis.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Gongyi Liu, Lini Zheng, Kui Tian, Haifeng Wang, Lung Wa Chung, Xumu Zhang, Xiu-Qin Dong
Summary: A highly efficient Ir/bisphosphine-thiourea catalytic system, ZhaoPhos, has been successfully developed for the asymmetric hydrogenation (AH) of challenging aryl substituted unprotected indoles, showing high reactivity and excellent stereoselective control. Various chiral indoline derivatives were obtained in good to high yields with excellent stereoselectivities. Anion-binding activation strategy played an important role in achieving both high reactivity and excellent stereoselectivity.
Article
Chemistry, Multidisciplinary
Chen-Qiang Deng, Jiao Liu, Jia-Hao Luo, Li-Jin Gan, Jin Deng, Yao Fu
Summary: A robust and highly active homogeneous chiral nickel-phosphine complex has been discovered for the asymmetric hydrogenation of aliphatic gamma- and delta-ketoacids. The mechanism studies revealed the activation of the substrate and stereoselectivity control through hydrogen bonds. Furthermore, this catalytic system can convert biomass feedstock into chiral products without loss of enantioselectivity.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Tian-Yi Wang, Xiao-Xuan Chen, Dong-Xing Zhu, Lung Wa Chung, Ming-Hua Xu
Summary: A highly selective C(sp(2))-H functionalization reaction catalyzed by rhodium(I)-diene has been developed, enabling the synthesis of α,β-unsaturated esters containing heteroatoms under mild reaction conditions. Mechanistic studies show that the substrate affects the reaction rate and selectivity.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Yunnan Xu, Yicong Luo, Jianxun Ye, Delong Liu, Wanbin Zhang
Summary: Novel axially chiral biphenyl diphosphine ligands E-n(m)-BridgePhos have been developed and successfully applied in the Rh-catalyzed enantioselective desymmetric hydrogenation, providing chiral compounds with high yields and excellent enantioselectivities, which serve as vital intermediates for the synthesis of analogues of chiral spirobenzylisoquinoline alkaloids.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Applied
Sudip Guria, Constantin G. Daniliuc, Ulrich Hennecke
Summary: Enantioselective iodocycloetherifications can be achieved using sterically highly demanding BINOL-based phosphoric acid diesters as catalyst, requiring cocatalysis by triphenylphosphine selenide. Good to excellent enantioselectivities can be achieved for a broad range of substrates with low catalyst and cocatalyst loadings of 1 mol %. Triphenylphosphine selenide itself does not strongly impact diastereoselectivity, but improves reactivity and enhances enantioselectivity when combined with a BINOL-based phosphoric acid diester.
ADVANCED SYNTHESIS & CATALYSIS
(2021)
Article
Chemistry, Multidisciplinary
Kui Tian, Gongyi Liu, Xiu-Qin Dong
Summary: This study successfully developed a highly enantioselective Rh-catalyzed partial hydrogenation reaction of unprotected simple 2-alkyl-5-aryl-disubstituted pyrroles, generating a series of chiral 1-pyrroline derivatives. This method features high yields, good enantioselectivities, easily accessible substrates, wide substrate scope, well functional group compatibility, and commercially available rhodium precursor and chiral ligand.
CHINESE CHEMICAL LETTERS
(2022)
Article
Chemistry, Organic
Ryukichi Takagi, Duyen Thi Duong
Summary: This study used density functional theory calculations to investigate the mechanism of enantioselective intramolecular hydroamination catalyzed by chiral binaphthol N-triflylphosphoramide (NPTA). It reveals the details of the hydrogen bonding mode between NPTA and the substrate, emphasizing the importance of the dual hydrogen binding properties of the thiourea moiety for the reactivity and stereoselectivity of the hydroamination.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2021)
Article
Chemistry, Organic
Chenxiao Qian, Meiwen Liu, Jianwei Sun, Pengfei Li
Summary: Propargylic alcohols are useful substrates in asymmetric reactions, and chiral phosphoric acid catalysis enables the synthesis of chiral tetrasubstituted allenes. This study expands the scope of propargylic alcohols and proposes a possible covalent activation mode.
ORGANIC CHEMISTRY FRONTIERS
(2022)
Article
Chemistry, Physical
Wei Hao, Candice L. Joe, Andrea Daru, Sloan Ayers, Antonio Ramirez, Bhupinder Sandhu, Ryan A. Daley, Jason S. Chen, Michael A. Schmidt, Donna G. Blackmond
Summary: The mechanism of asymmetric hydrogenation of 2-pyridyl alkenes catalyzed by chiral Rh-phosphine complexes has been studied at ambient temperature. The reaction involves reversible substrate binding followed by rate-determining hydrogen addition. Substrate binding occurs only through the pyridine nitrogen and is not influenced by hydrogen pressure. Catalyst deactivation is observed due to the presence of an off-cycle Rh-hydride species. The stereochemical outcome in this system correlates with the relative stability of the E and Z rotamers of the substrate.
Article
Chemistry, Organic
Yu Zhang, Shulei Hu, Yazhou Li, Yongkun Wang, Tao Yu, Qiangqiang Chen, Jiang Wang, Hong Liu
Summary: Here, a novel strategy for constructing maleimide-containing peptides and cyclic peptides using Rh(III)-catalyzed tryptophan (Trp) (C7) alkenylation was reported, which is challenging due to the inherent reactivity of the indole benzenoid ring. This method is scalable and exhibits broad substrate scope. The utility of this protocol could further be demonstrated by the synthesis of peptide conjugates with natural products and amino acids as well as the construction of maleimide-braced cyclic peptides.
Article
Chemistry, Organic
Yu Zhang, Shulei Hu, Yazhou Li, Yongkun Wang, Tao Yu, Qiangqiang Chen, Jiang Wang, Hong Liu
Summary: Here, a novel strategy for constructing maleimide-containing peptides and cyclic peptides using Rh(III)-catalyzed tryptophan alkenylation is reported, which is challenging due to the inherent reactivity of the indole benzenoid ring. This method is scalable and exhibits broad substrate scope. The utility of this protocol is demonstrated by the synthesis of peptide conjugates with natural products and amino acids, as well as the construction of maleimide-braced cyclic peptides.
Article
Chemistry, Organic
Yu Zhang, Shulei Hu, Yazhou Li, Yongkun Wang, Tao Yu, Qiangqiang Chen, Jiang Wang, Hong Liu
Summary: Here, a novel strategy for constructing maleimide-containing peptides and cyclic peptides using Rh(III)-catalyzed tryptophan (Trp) (C7) alkenylation is reported. This method, which is challenging due to the inherent reactivity of the indole benzenoid ring, is scalable and exhibits broad substrate scope. The utility of this protocol is further demonstrated by the synthesis of peptide conjugates with natural products and amino acids, as well as the construction of maleimide-braced cyclic peptides.
Article
Chemistry, Organic
Yuting Feng, Peter Viereck, Shi-Guang Li, Youla S. Tsantrizos
Summary: An asymmetric Rh-catalyzed transfer hydrogenation method has been developed for the conversion of alpha-enamidophosphonates to alpha-aminophosphonates. This method is applicable to a variety of substrates and achieves high yields and enantiomeric excess.
Article
Chemistry, Physical
Qian Wang, Jialing Lan, Rong Liang, Yihao Xia, Lei Qin, Lung Wa Chung, Zhiping Zheng
Summary: In this study, a new application of the Grubbs catalysts in hydrogen production from aqueous-phase methanol reforming was reported, showing that the G-III catalyst achieved the best performance among those tested and can also be used for other dehydrogenation reactions. Mechanistic studies and DFT calculations revealed an unusual substrate-assisted metathesis pathway, shedding light on the reaction mechanism and suggesting new opportunities in catalyst design for clean and renewable energies.
Review
Chemistry, Multidisciplinary
Jialing Lan, Xin Li, Yuhong Yang, Xiaoyong Zhang, Lung Wa Chung
Summary: Homogeneous catalysis and biocatalysis have found wide applications in synthetic, medicinal, and energy chemistry as well as synthetic biology. Computational chemistry has become an essential tool to understand structures and reaction mechanisms in catalysis. The synergy between computational and experimental chemistry deepens our understanding of mechanisms and promotes the design of new catalysts.
ACCOUNTS OF CHEMICAL RESEARCH
(2022)
Article
Chemistry, Organic
Huaxin Yang, Yang Zhou, Zhihan Zhang, Jialin Wen, Xumu Zhang
Summary: We report a convenient method for converting olefins to organic iodides and amines using a specific catalyst, molecular hydrogen, and an electrophilic iodine reagent. High yields and regioselectivities were achieved under mild conditions, and C-N products were obtained through specific workup steps. Control experiments and DFT calculations were conducted to exclude potential reaction pathways.
Article
Chemistry, Multidisciplinary
Gongyi Liu, Lini Zheng, Kui Tian, Haifeng Wang, Lung Wa Chung, Xumu Zhang, Xiu-Qin Dong
Summary: A highly efficient Ir/bisphosphine-thiourea catalytic system, ZhaoPhos, has been successfully developed for the asymmetric hydrogenation (AH) of challenging aryl substituted unprotected indoles, showing high reactivity and excellent stereoselective control. Various chiral indoline derivatives were obtained in good to high yields with excellent stereoselectivities. Anion-binding activation strategy played an important role in achieving both high reactivity and excellent stereoselectivity.
Article
Chemistry, Multidisciplinary
Tian-Yi Wang, Xiao-Xuan Chen, Dong-Xing Zhu, Lung Wa Chung, Ming-Hua Xu
Summary: A highly selective C(sp(2))-H functionalization reaction catalyzed by rhodium(I)-diene has been developed, enabling the synthesis of α,β-unsaturated esters containing heteroatoms under mild reaction conditions. Mechanistic studies show that the substrate affects the reaction rate and selectivity.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Inorganic & Nuclear
Jialing Lan, Tonghuan Zhang, Yuhong Yang, Xin Li, Lung Wa Chung
Summary: Transition-metal-catalyzed amination of aryl halides is a useful method for synthesizing medicinal compounds, organic functional materials, and agrochemical compounds. A systematic DFT study has revealed the mechanism of Co(I)-catalyzed amination of aryl halides, with dissociative C-I activation pathway being the most favorable.
INORGANIC CHEMISTRY
(2022)
Article
Chemistry, Physical
Runtong Zhang, Xin Yan, Fanfu Guan, Yu Qian, Jianghua Peng, Jianxin Wang, Baode Ma, Shao-Tao Bai, Jialin Wen, Xumu Zhang
Summary: This article reports the application of a novel tetraphosphite ligand in the ISO-HF of C4 Raffinate. The ligand showed high turnover frequencies and regioselectivities in the reaction, and demonstrated excellent durability in large-scale continuous reactors.
JOURNAL OF CATALYSIS
(2022)
Article
Chemistry, Multidisciplinary
Shaoke Zhang, Rong Zhou, Ya-Nan Duan, Yang Zhou, Xumu Zhang, Jialin Wen
Summary: In this study, a nucleophilic hydrogenation reaction for less electron-rich arenes and heteroarenes was reported. The catalytic activity and electrophilicity of the substrates were analyzed, and a method for synthesizing more challenging substituted benzenes was proposed based on computational modifications of the catalyst.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Chemistry, Physical
Zhifeng Ma, Zeyin Yan, Xin Li, Lung Wa Chung
Summary: In this study, the effects of external electric fields (EEFs) on three reactions involving hydrogen or carbon were extensively investigated. The study revealed that oriented EEFs can significantly reduce the barrier and increase the reaction rates. Furthermore, EEFs can modulate tunneling reactions and control the site selectivity of molecules with similar reactive sites.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Fanfu Guan, Yu Qian, Peiqi Zhang, Runtong Zhang, Xumu Zhang, Jialin Wen
Summary: A novel microreactor (Flashstop reactor) combining flash chemistry and radial synthesis was designed to study the isomerization process of hydroformylation by a Rh/tetraphosphite catalyst in seconds. The initial 313 seconds showed the isomerization of 60-99% of 1-octene to 2- and 3-octenes before aldehyde formation, with two different types of isomerization reactions being observed. A monohydride complex without CO ligand was proposed to account for the ultrafast isomerization in the first 30 seconds, and the isomerization rate with this complex was calculated to be faster than the well-known H(CO)Rh(P-P) species. Experimental and DFT computational studies support this assumption, showing that the Flashstop reactor is a powerful tool for analyzing kinetics in gas-liquid biphasic reactions in seconds to minutes.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Mingkang Zhou, Yaodong Lin, Xiao-Xuan Chen, Guangqing Xu, Lung Wa Chung, Wenjun Tang
Summary: We report the chiral diboron-templated asymmetric homocoupling of aryl alkyl ketimines, leading to the formation of chiral vicinal tetrasubstituted diamines with high enantioselectivities and good to high yields. This powerful and efficient reaction is achieved by rational design and engineering of chiral diborons, which participate in a [3,3]-sigmatropic rearrangement. DFT studies reveal that different conformational assembling strategies of chiral diborons ensure the excellent enantioselectivity in the tight concerted transition states.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Organic
Rong Liang, Qinghai Zhou, Xin Li, Ming Wah Wong, Lung Wa Chung
Summary: The macrocycle effect of [2]rotaxane on the highly trans-stereoselective cyclization reaction of N-benzylfumaramide has been extensively studied. Computational results suggest that the most favorable mechanism involves deprotonation of a N-benzyl group of the fumaramide substrate by CsOH, followed by C-C bond formation and protonation by an amide functional group of the macrocycle. The trans-selective cyclization within the rotaxane is attributed to higher distortion energy caused by the twisted cis-fumaramide conformation enforced by the rotaxane.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Lei Yang, Xuefeng Tan, Menglong Zhao, Jialin Wen, Xumu Zhang
Summary: A ferrocene-based tetradentate ligand with modular synthesis and rigid skeleton was designed and synthesized, and its iron(II) complex was found to facilitate the asymmetric direct hydrogenation of ketones without the need for strong-field ligands such as CO and isocyanide. The use of a hydride donor LiAlH4 converted non-reactive Fe(II) species to reactive Fe(II) hydride species, enabling the preparation of various chiral alcohols with satisfactory yields and enantioinduction, including the intermediate for montelukast.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Organic
Liyao Zeng, Menglong Zhao, Bijin Lin, Jingyuan Song, James H. R. Tucker, Jialin Wen, Xumu Zhang
Summary: A new cobalt catalytic system for asymmetric hydrogenation of ketones was developed using ferrocene-based secondary phosphine oxide ligands. The coordination pattern of cobalt with the ligands was confirmed by X-ray diffraction. The cobalt complexes exhibited high reactivities (up to 99% yield) and good to excellent enantioselectivities (up to 92% ee) in the hydrogenation of ortho-substituted diaryl ketones. Moreover, the diferrocenyl cobalt complex showed intriguing UV-vis absorption and electrochemical properties.
Article
Chemistry, Multidisciplinary
Xin Chang, Xue-Tao Liu, Fangfang Li, Yuhong Yang, Lung Wa Chung, Chun-Jiang Wang
Summary: A series of benzofulvenes without electron-withdrawing substituents were used as 2π-type dipolarophiles in Cu(i)-catalyzed asymmetric 1,3-dipolar cycloaddition reactions. The non-benzenoid aromatic characteristic of benzofulvenes served as a key driving force for their activation. The methodology allowed for the synthesis of multi-substituted chiral spiro-pyrrolidine derivatives with exclusive chemo-/regioselectivity and high to excellent stereoselectivity.
