Article
Chemistry, Physical
Gabriel Durin, Jean-Claude Berthet, Emmanuel Nicolas, Thibault Cantat
Summary: Efficient synthesis of hydrosilanes was achieved by catalytic hydrogenolysis of chlorosilanes using an iridium (III) pincer catalyst. A careful selection of nitrogen base allowed for high yields (up to 98%) of Me3SiH, Et3SiH, and Me2SiHCl directly from their corresponding chlorosilanes.
Article
Chemistry, Multidisciplinary
Wei Zhao, Wenji Wang, Huan Zhou, Qishan Liu, Zhiqing Ma, Haizhou Huang, Mingxin Chang
Summary: A one-pot asymmetric hydrogenation of pyridines with subsequent N-alkylation using a traceless Bronsted acid activation strategy is reported. The reaction exhibits high stereoselectivity and can be used to synthesize indolizidines and quinolizidines. Experimental and theoretical studies reveal that chloride anion and noncovalent interactions play important roles in determining the stereoselectivity of the reaction.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Applied
Sarun Chanklang, Wongsaphat Mondach, Pooripong Somchuea, Thongthai Witoon, Metta Chareonpanich, Kajornsak Faungnawakij, Anusorn Seubsai
Summary: The hydrogenolysis of glycerol to 1,3-propanediol was studied using Ir-ReOx catalysts supported on H-ZSM-5. The composition and metal loading of the catalyst strongly affected the glycerol conversion and 1,3-propanediol yield. The addition of Re to the catalyst promoted higher metal dispersion of Ir and smaller Ir particles. Additionally, a strong electronic interaction between Ir and Re was observed. The study also showed that increasing the temperature and reaction time resulted in higher glycerol conversion but lower 1,3-propanediol selectivity, while increasing the pressure had a positive effect on 1,3-propanediol selectivity.
Article
Chemistry, Multidisciplinary
Zhi Yang, Yu Chen, Linxi Wan, Yuxiao Li, Dan Chen, Jianlin Tao, Pei Tang, Fen-Er Chen
Summary: A highly enantioselective method for the complete hydrogenation of pyrimidinium salts using Ir/(S,S)-f-Binaphane complex as the catalyst was developed. This method provides easy access to fully saturated chiral hexahydropyrimidines, which are prevalent in many bioactive molecules. The reactions exhibit high yields and enantioselectivities under mild reaction conditions without additives. Successful application of this methodology in a continuous flow fashion further extends its practical utility.
Article
Chemistry, Physical
Emanuel M. Virgilio, Maria E. Sad, Cristina L. Padro
Summary: This study investigated the influence of temperature, H2 pressure, and erythritol concentration on the hydrogenolysis of erythritol using Ir/ReOx/TiO2 catalyst. The results showed that different reaction pathways were affected to varying degrees by temperature, H2 pressure, and erythritol concentration, with C-C bond cleavage requiring higher energy.
APPLIED CATALYSIS A-GENERAL
(2022)
Article
Chemistry, Organic
Congcong Yin, Yingmin Pan, Longsheng Zheng, Bijin Lin, Jialin Wen, Xumu Zhang
Summary: Enantioselective hydrogenation of imines via an outer-sphere mechanism was achieved using an iridium tridentate catalyst, resulting in high enantioselectivities and turnover numbers up to 10,000. This method was successfully applied in the synthesis of chiral amines with an alpha-stereocenter, allowing for the preparation of cinacalcet with remarkably high enantioselectivity.
ORGANIC CHEMISTRY FRONTIERS
(2021)
Article
Chemistry, Physical
Xiwen Zhang, Yubing Lu, Libor Kovarik, Prasanna Dasari, Dick Nagaki, Ayman M. Karim
Summary: Hydrogenolysis of alkanes on transition metal heterogeneous catalysts is structure sensitive, with Ir particle size affecting n-butane hydrogenolysis activity. Results show that larger Ir particle sizes within the 1-3 nm range lead to increased activity, peaking around 1.4-1.6 nm before decreasing. At low temperatures, product distribution is dominated by central and terminal C-C bond cleavage, with selectivity depending on the size of Ir particles, increasing with sizes smaller than 1.4 nm.
JOURNAL OF CATALYSIS
(2021)
Article
Chemistry, Multidisciplinary
Xiang Li, Gao-Wei Wang, Li-Xia Liu, Chang-Bin Yu, Yong-Gui Zhou
Summary: Here, the authors describe the first example of palladium-catalyzed asymmetric hydrogenolysis of easily accessible aryl triflates for the construction of axially chiral biaryl scaffolds. The resulting chiral biaryl compounds were used to prepare axially chiral monophosphine ligands, which were further employed in palladium-catalyzed asymmetric allylic alkylation with excellent enantioselectivities and high branched and linear ratios, highlighting the potential utility of this methodology.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Wu-Lin Yang, Xin-Yu Shang, Tao Ni, Hui Yan, Xiaoyan Luo, Hanliang Zheng, Zhong Li, Wei-Ping Deng
Summary: In this study, an efficient iridium/silver/acid ternary catalytic system was developed for the synthesis of bisbenzannulated [6,6]-spiroketals and [6,6]-spiroaminals with high diastereo- and enantioselectivities. The reaction mechanism and stereochemistry were elucidated through experimental studies and theoretical calculations.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Jian Zhang, Wu-Lin Yang, Hanliang Zheng, Yi Wang, Wei-Ping Deng
Summary: This study reports an unprecedented asymmetric gamma-allylic alkylation method using the Sc/Ir dual catalysis system, which provides synthetically versatile gamma-allylic crotonaldehydes with high efficiency and excellent selectivities. The dienolates, without essential auxiliary groups, are generated in situ through scandium triflate-mediated Meinwald rearrangement in an atom-economical manner. A Sc/Ir bimetallic catalytic cycle is proposed to explain the reaction mechanism using computational density functional theory calculations.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Zhaofeng Gao, Jingwen Liu, Haizhou Huang, Huiling Geng, Mingxin Chang
Summary: The research reports on efforts to merge two asymmetric reductive amination reactions into a single-step transformation, utilizing specific catalyst and acid additives to successfully synthesize enantiopure secondary amine products.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Jose A. Carmona, Patricia Rodriguez-Salamanca, Rosario Fernandez, Jose M. Lassaletta, Valentin Hornillos
Summary: An atroposelective Ir-catalyzed dynamic kinetic resolution (DKR) of 2-(quinolin-8-yl)benzaldehydes/1-naphthaldehydes is achieved by transfer hydrogenative coupling of allyl acetate. The reaction leads to the installation of central and axial chirality, with high diastereoselectivities and excellent enantioselectivities when ortho-cyclometalated iridium-DM-BINAP is used as the catalyst. The racemization of the substrates is facilitated through a designed transient Lewis acid-base interaction between the quinoline nitrogen atom and the aldehyde carbonyl group.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Pep Rojo, Medea Molinari, Albert Cabre, Clara Garcia-Mateos, Antoni Riera, Xavier Verdaguer
Summary: Chiral compounds containing nitrogen heteroatoms are crucial for the chemical, pharmaceutical, and agrochemical industries. In this study, a series of P-stereogenic phosphinooxazoline iridium catalysts were synthesized and successfully used in the asymmetric hydrogenation of N-Boc-2,3-diarylallyl amines, achieving high enantioselectivity. The synthetic utility of the obtained 2,3-diarylpropyl amines was also demonstrated.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Pusu Yang, Rui-Xiang Wang, Yuan-Zheng Cheng, Chao Zheng, Shu-Li You
Summary: This study describes an iridium-catalyzed asymmetric allylic benzylation reaction under light irradiation. 2-methylbenzophenone derivatives were activated by ultraviolet light, enabling high enantioselectivity without the use of strong bases or pre-activation.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Haibo Wu, Hao Su, Erik J. Schulze, Bram B. C. Peters, Mark D. Nolan, Jianping Yang, Thishana Singh, Marten S. G. Ahlquist, Pher G. Andersson
Summary: The study presents a highly efficient desymmetrization of 1,4-dienes through iridium-catalyzed site- and enantioselective hydrogenation, allowing the installation of two adjacent stereogenic centers. High yields and excellent selectivities were achieved for a range of substrates, and the methodology was demonstrated by synthesizing key intermediates of natural products.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Peng Zhang, Xiao-Mei Wang, Qi Xu, Chang-Qiu Guo, Peng Wang, Chuan-Jun Lu, Ren-Rong Liu
Summary: In this study, a Pd-catalyzed cross-coupling strategy was employed for the synthesis of N-C axially chiral biaryl molecules with excellent enantioselectivities and good yields. The practicality of this reaction was demonstrated in the synthesis of biologically relevant molecules.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Organic
Qi Xu, Huan Zhang, Fang-Bei Ge, Xiao-Mei Wang, Peng Zhang, Chuan-Jun Lu, Ren-Rong Liu
Summary: In this study, we demonstrate that copper(I) catalysis using a bis(phosphine) dioxide ligand can efficiently catalyze the desymmetric C-H arylation of prochiral bipyrroles with excellent enantioselectivities. More than 50 nitrogen-nitrogen atropisomers were achieved in good to excellent yields. The mild reaction conditions and good functional group compatibility on arenes and diaryliodonium salts make this method highly versatile.
Article
Chemistry, Organic
Peng Zhang, Jia Feng, Ren-rong Uu
Summary: Benzimidazole atropisomers with a C-N axis are privileged structural frameworks in pharmaceutical and natural products, and their asymmetric synthesis has attracted increasing attention. This paper briefly discusses recent advances in the asymmetric synthesis of benzimidazole atropisomers with a C-N axis, focusing on the recently developed palladium-catalyzed intramolecular Buchwald-Hartwig amination strategy.
Article
Chemistry, Organic
Wang Yao, Chuan-Jun Lu, Jia Feng, Ren-Rong Liu
Summary: This study reports a novel method for the enantioselective synthesis of axially chiral 2,2' difluoro-1-biaryls using a palladium and chiral amino acid catalyzed atroposelective C-H olefination. The results demonstrate that a variety of polyfluoro-substituted biaryls can be efficiently synthesized under mild conditions with excellent enantioselectivity.
Article
Chemistry, Multidisciplinary
Chang-Qiu Guo, Chuan-Jun Lu, Li-Wen Zhan, Peng Zhang, Qi Xu, Jia Feng, Ren-Rong Liu
Summary: This study reports a new catalyst that successfully catalyzes the enantioselective coupling reaction between quinone esters and anilines, resulting in the formation of N-aryl quinone atropisomers with a unique intramolecular hydrogen bond. This method has the potential to be used for the synthesis of structurally diverse secondary amine atropisomers.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Peng Zhang, Qi Xu, Xiao-Mei Wang, Jia Feng, Chuan-Jun Lu, Yingzi Li, Ren-Rong Liu
Summary: The first enantioselective synthesis of N-N bisindole atropisomers via palladium-catalyzed construction of one indole skeleton is reported in this study. A wide variety of N-N axially chiral bisindoles were generated with good yields and excellent enantioselectivities through a cascade condensation/N-arylation reaction. The reaction mechanism and enantiocontrol were further investigated using density functional theory (DFT) calculations.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Review
Chemistry, Multidisciplinary
Chuan-Jun Lu, Qi Xu, Jia Feng, Ren-Rong Liu
Summary: In the past few decades, the Buchwald-Hartwig reaction has played a vital role in the pharmaceuticals, materials, and catalysis fields as a powerful tool for forming C-N bonds. However, the development of asymmetric Buchwald-Hartwig amination reactions for constructing centered chirality, planar chirality, and axial chirality has been limited due to substrate scope and ligand design challenges. Recent interest in the synthesis of C-N/N-N atropisomers has led to a resurgence in asymmetric Buchwald-Hartwig amination chemistry, providing a practical protocol for the preparation of C-N atropisomers. This review discusses reported protocols and their chemical practicality.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Polymer Science
Bozhen Wu, Renrong Liu, Yuhao Yang, Honghao Zhu, Yujing Yu, Jiang Huang, Yulin Li
Summary: This study develops nickel-coated silicon carbide whiskers/graphene nanosheets/polyvinylidene fluoride composites with an asymmetric structure for high electromagnetic interference shielding capability and absorption efficiency. The composites show different shielding mechanisms when electromagnetic waves are incident from different faces.
JOURNAL OF APPLIED POLYMER SCIENCE
(2023)
Article
Chemistry, Multidisciplinary
Wang Yao, Chuan-Jun Lu, Li-Wen Zhan, Yi Wu, Jia Feng, Ren-Rong Liu
Summary: In this study, a palladium-catalyzed enantioselective C-H activation method for pyrroles was reported, which successfully synthesized structurally diverse indole-pyrrole atropisomers with a chiral N-N axis, showing high yields and enantioselectivities. Furthermore, the kinetic resolution of trisubstituted N-N heterobiaryls with more sterically demanding substituents was also achieved. This versatile method enables the rapid and selective functionalization of pyrroles, facilitating the synthesis of valuable and complex N-N atropisomers.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Physical
Peng Zhang, Chang-Qiu Guo, Wang Yao, Chuan-Jun Lu, Yingzi Li, Robert S. S. Paton, Ren-Rong Liu
Summary: A palladium-catalyzed amination method was developed to construct structurally diverse N-C atropisomers, and the reaction mechanism was explained using density functional theory calculations. This method has a broad substrate scope, high stereoselectivity, a simple catalytic system, good functional group tolerance, and dynamic kinetic resolution.
Review
Chemistry, Multidisciplinary
Jia Feng, Chuan-Jun Lu, Ren-Rong Liu
Summary: Atropisomers with rotation-restricted axis are common in natural products, chiral ligands, and drugs, which has led to an increase in asymmetric synthesis. However, the research on N-X atropisomers is not as developed as the C-C atropisomer analogue. N-X atropisomers could offer divergent scaffolds, which are important in bioactive molecules. The asymmetric synthesis of N-X atropisomers is both appealing and challenging.
ACCOUNTS OF CHEMICAL RESEARCH
(2023)
Article
Chemistry, Multidisciplinary
Li-Wen Zhan, Chuan-Jun Lu, Jia Feng, Ren-Rong Liu
Summary: This study reports for the first time that palladium compounds can catalyze the hydroarylation of 1-alkynylindoles with organoborons, resulting in the synthesis of chiral C-N atropisomers. The reaction conditions are mild and lead to excellent regio-, stereo- (Z-selectivity), and enantioselectivity. The simplicity, high stereoselectivity, and good functional group tolerance of this catalytic system make it highly attractive.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Jia Feng, Ren-Rong Liu
Summary: This article summarizes the asymmetric synthesis of N-N biaryl atropisomers and their importance in natural products, drug design, and asymmetric synthesis. The article introduces several synthetic strategies for N-N biaryl atropisomers and offers an outlook for future research.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Organic
Huan Zhang, Yi Ding, Mei-Ru Zhang, Chuan-Jun Lu, Jia Feng, Ren-Rong Liu
Summary: Here, the authors report a palladium-catalyzed double C-N coupling reaction between 9H-carbazol-9-amines and 2,2'-dibromo-1,1'-biphenyl. This method provides a route to synthesize N,N'-bicarbazole scaffolds, which are commonly used as linkers in the construction of functional covalent organic frameworks (COFs). The authors successfully synthesized various substituted N,N'-bicarbazoles in moderate to high yields, and demonstrated the potential application of this method in the synthesis of COF monomers like tetrabromide 4 and tetraalkynylate 5.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Qi Xu, Chuan-Jun Lu, Chang-Qiu Guo, Jia Feng, Ren-Rong Liu
Summary: This study reports a new palladium-catalyzed rearrangement reaction of VCPs (dienyl or trienyl cyclopropanes) for the construction of functionalized cyclopentene units with high yields and excellent enantioselectivities. The method has significant implications for the synthesis of organic compounds containing cyclopentanes or cyclopentenes.
Article
Chemistry, Organic
Geeta Devi Yadav, Pooja Chaudhary, Balaram Pani, Surendra Singh
Summary: Chiral transition metal complexes with privileged ligands are efficient catalysts for various asymmetric organic transformations. Transition metal complexes of C1-symmetric pyrrolidine-based ligands have been widely used in asymmetric organic reactions. However, a comprehensive review article on the transition metal complexes of chiral C1-symmetric pyrrolidine-based ligands derived from (L)-proline has not been published.
TETRAHEDRON LETTERS
(2024)
