Article
Chemistry, Multidisciplinary
Jun He, Wen Liu, Jing Zhang, Ziwei Zhong, Lili Lin, Xiaoming Feng
Summary: In this study, a diastereo- and enantioselective tandem cycloisomerization/[4 + 2]-cycloaddition reaction of cyclopropyl tethered allenyl ketones with alpha,beta-unsaturated carbonyl compounds was successfully achieved for the first time under mild reaction conditions using bimetallic silver (I)/chiral metal-N,N '-dioxide catalysts. This provided a facile and atom-economic route to enantioenriched polysubstituted furopyran derivatives with good results. Possible transition state models were proposed to explain the stereoinduction.
SCIENCE CHINA-CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Maosheng Li, Shuai Zhang, Xiaoyong Zhang, Yanchao Wang, Jinlong Chen, Youhua Tao, Xianhong Wang
Summary: The study describes an effective unimolecular anion-binding organocatalysis for ring-opening polymerization of O-carboxyanhydrides (OCAs), achieving the synthesis of highly isotactic poly(phenyllactic acid) (Ph-PLA) through a dynamic cooperative anion-binding mechanism. This approach addresses the challenge of synthesizing high molecular weight stereoregular polyesters by facilitating efficient chain propagation and maintaining high selectivity for OCA ring-opening over side reactions.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Organic
Angel Ho, Austin Pounder, Samuel Koh, Matthew P. Macleod, Emily Carlson, William Tam
Summary: This study demonstrates the ability of carboxylic acid tethered CPOBD to undergo ring-opening reactions under mild acidic conditions, with high regioselectivity towards type 3 ring-opened products. Substitution at specific positions of CPOBD was found to hinder the ring-opening reactions and decrease the yields of ring-opened products. Overall, this work represents the first examples of acid-catalyzed intramolecular ring-opening reactions of CPOBD with carboxylic acid nucleophiles.
SYNTHESIS-STUTTGART
(2022)
Article
Chemistry, Applied
Jun-Long Zhan, Lin Zhu, Wei Ren, Bing-Jie Wang, Xin-Ming Zhao, Xin-Ru Zhang, Xin-Yu Zhang, Yao-Qiang Xie
Summary: A feasible and umpolung strategy for synthesizing diverse beta-amino ketones was achieved through TEMPO mediated C-N coupling of cyclopropanols with nitrogen nucleophiles. Mechanism studies showed that enones derived from cyclopropanols are key intermediates and TEMPO plays multiple roles. This protocol offers broad substrate scope, good scalability, and good to excellent yields, providing an alternative approach to the synthesis of structurally important beta-amino ketone scaffolds under metal and additive-free conditions.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Letter
Chemistry, Organic
Bing Yuan, Chang Zhang, Haiyan Dong, Chuan Wang
Summary: By merging C-C and C-F bond cleavage, a regioselective ring opening/gem-difluoroallylation of cyclopropyl ketones with a-trifluoromethylstyrenes was developed, which proceeds under the catalysis of iron with the combination of manganese and TMSCl as the reducing agents. This reaction provides a new entry to the synthesis of carbonyl-containing gem-difluoroalkenes. Remarkably, the ketyl radical-induced selective C-C bond cleavage and the following generation of more-stable carbon-centered radicals enable complete regiocontrol of this ring opening reaction for various substitution patterns of the cyclopropane ring.
Article
Chemistry, Physical
Bing Yuan, Decai Ding, Chuan Wang
Summary: In this study, we have successfully implemented a reductive strategy for the ring opening reaction of aryl cyclopropylketones with unactivated alkyl bromides. The nickel-catalyzed reductive Csp3-Csp3cross-coupling reaction proceeds with complete regioselectivity, bypassing the need for pregenerated organometallics and allowing for efficient synthesis of alkylated ketones with high step economy and functionality tolerance.
Article
Chemistry, Multidisciplinary
Shu-Sen Li, Shuo Sun, Jianbo Wang
Summary: The catalytic asymmetric trifluoromethylation of cyclic ketones via a Sc-III/chiral bisoxazoline-catalyzed homologation reaction using 2,2,2-trifluorodiazoethane (CF3CHN2) as the CF3 source is an efficient method to generate chiral alpha-trifluoromethyl cyclic ketones with excellent diastereoselectivity and enantioselectivity.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Physical
Lantao Liu, Fangyuan Cheng, Chenxiang Meng, An-An Zhang, Mingliang Zhang, Kai Xu, Naoki Ishida, Masahiro Murakami
Summary: A Pd-catalyzed chemo-, regio-, and enantioselective ring-closing/ring-opening cross coupling reaction has been developed with diverse aryl halide-tethered alkenes and benzocyclobutenols as substrates. This method provides a convenient approach to chiral 2,3-dihydrobenzofurans with excellent enantioselectivities, and has been applied in the concise synthesis of analogues of cannabinoid receptor 2 agonists.
Article
Chemistry, Multidisciplinary
Vibha V. Kanale, Christopher Uyeda
Summary: Cobalt catalysts facilitate highly enantioselective ring-opening reactions of 2,5-dihydrofurans using vinylidenes. The resulting products are acyclic organozinc compounds, capable of further functionalization with an electrophile. The proposed mechanism involves the formation of a cobalt vinylidene species that adds to the alkene via a [2+2]-cycloaddition pathway, followed by ring-opening through outer-sphere & beta;-O elimination assisted by a ZnX2 Lewis acid. DFT models explain the observed stereochemical outcome by suppressing competing inner-sphere syn & beta;-H and & beta;-O elimination pathways due to the geometric constraints of the metallacycle intermediate. Cobalt catalysts also promote enantioselective ring-opening reactions of unstrained heterocycles via reductive addition of 1,1-dichloroalkenes. The resulting products are acyclic homoallylic alcohols with a vinylzinc motif, which can be further modified with an electrophile. Mechanistic studies suggest that the ring-opening occurs through outer-sphere & beta;-O elimination facilitated by a Zn(II) Lewis acid.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Organic
Huiqing Deng, Qihang Cheng, Hu Cai, Dongxin Zhang, Qian-Feng Zhang
Summary: A series of 1,6-diketone derivatives were synthesized through copper (II) trifluoromethanesulfonate catalyzed ring-opening of cyclopropyl ketones with 1,3-diketones, followed by DBU-promoted retro-Claisen reactions. The acyclic 1,3-diketones selectively acted as carbon-nucleophiles and added to the donor-acceptor cyclopropanes. The resulting ring-opening products underwent C-C bond cleavage to yield 1,6-diketone derivatives concisely. (c) 2022 Elsevier Ltd. All rights reserved.
TETRAHEDRON LETTERS
(2023)
Article
Chemistry, Applied
Claire Segovia, Jeremy Godemert, Jean-Francois Briere, Vincent Levacher, Sylvain Oudeyer
Summary: An organocatalyzed one-pot sequential deracemization of aromatic ketones with a stereogenic center at the alpha-position was achieved through an acid-base strategy, in which enantioselective protonation reaction played a key role. This protocol provides enantioenriched ketones with up to 89% ee without isolating sensitive intermediates like silyl enolates. Water was found to be crucial in this process. This one-pot sequence serves as a valuable extension to previously reported chemically driven red-ox protocols, expanding the range of molecules eligible for deracemization.
ADVANCED SYNTHESIS & CATALYSIS
(2022)
Article
Chemistry, Multidisciplinary
Juana M. Perez, Roxana Postolache, Marta Castineira Reis, Esther G. Sinnema, Denisa Vargova, Folkert de Vries, Edwin Otten, Luo Ge, Syuzanna R. Harutyunyan
Summary: Chiral Mn(I) complexes have been shown to activate H-P bonds, providing a general method for the hydrophosphination of internal and terminal alpha,beta-unsaturated nitriles. Metal-ligand cooperation, a previously unconsidered strategy for catalytic H-P bond activation, plays a key role in the mechanistic action of the Mn(I)-based catalyst. Computational studies support a stepwise mechanism for the hydrophosphination reaction and offer insights into the origin of enantioselectivity.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Review
Chemistry, Multidisciplinary
Xi Wang, Youbin Peng, Ling Zhao, Xiaohong Huo, Wanbin Zhang
Summary: Compared to the stereocontrol of the stereocenter at the allyl unit, asymmetric induction of prochiral nucleophiles is a challenging task in Pd-catalyzed asymmetric allylic substitutions due to the remote distance between the chiral catalyst and the prochiral nucleophile. Extensive efforts have been made to address this challenge through the design of chiral ligands. Recently, synergistic catalysis, including bimetallic catalysis and Pd/organocatalysis, has gained attention for its potential advantages in improving reactivity and selectivity, and providing a simple and unified method for the stereocontrol of prochiral nucleophiles. This review summarizes the history and advances in this field.
SCIENCE CHINA-CHEMISTRY
(2023)
Article
Chemistry, Organic
Lea Grefe, Esteban Mejia
Summary: This review discusses the development of catalytic systems for the ring-opening copolymerization of epoxides and CO2 to produce polycarbonates, focusing on systems made from earth-abundant metals. It emphasizes on bi- and multimetallic heterogeneous catalytic systems developed since 1985 and homogeneous catalysts reported after 2015, with a focus on the structural features of these complexes and their corresponding reactivities.
Review
Chemistry, Physical
Claire A. L. Lidston, Sarah M. Severson, Brooks A. Abel, Geoffrey W. Coates
Summary: The ring-opening copolymerization (ROCOP) of epoxides with CO2 or cyclic anhydrides using multifunctional catalysts has been explored as a versatile route for synthesizing a wide range of polycarbonate and polyester copolymers. Covalently tethering the Lewis acid catalyst and cocatalyst together has been shown to increase both catalyst activity and selectivity in epoxide ROCOP. This review examines the development of multifunctional catalysts for copolymerization of epoxides with CO2, cyclic anhydrides, carbonyl sulfide (COS), and cyclic thioanhydrides, and evaluates how the mechanisms of these catalysts lead to improved activity and selectivity in ROCOP.
Article
Chemistry, Organic
Xuan Fu, Lili Lin, Yong Xia, Pengfei Zhou, Xiaohua Liu, Xiaoming Feng
ORGANIC & BIOMOLECULAR CHEMISTRY
(2016)
Article
Chemistry, Multidisciplinary
Yuting Liao, Xiaohua Liu, Yu Zhang, Yali Xu, Yong Xia, Lili Lin, Xiaoming Feng
Article
Chemistry, Physical
Yuting Liao, Baixin Zhou, Yong Xia, Xiaohua Liu, Lili Lin, Xiaoming Feng
Article
Chemistry, Organic
Yong Xia, Fenzhen Chang, Lili Lin, Yali Xu, Xiaohua Liu, Xiaoming Feng
ORGANIC CHEMISTRY FRONTIERS
(2018)
Article
Chemistry, Multidisciplinary
Yong Xia, Lin Wang, Armido Studer
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2018)
Article
Chemistry, Organic
Lin Wang, Yong Xia, Klaus Bergander, Armido Studer
Article
Multidisciplinary Sciences
Ziming Yang, Xuan Fu
JOVE-JOURNAL OF VISUALIZED EXPERIMENTS
(2018)
Article
Chemistry, Multidisciplinary
Yong Xia, Armido Studer
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2019)
Article
Chemistry, Multidisciplinary
Xuan Fu, Yiju Liao, Christopher R. Glein, Megan Jamison, Kyle Hayes, Jared Zaporski, Ziming Yang
ACS EARTH AND SPACE CHEMISTRY
(2020)
Article
Chemistry, Multidisciplinary
Xuan Fu, Yiju Liao, Alexandria Aspin, Ziming Yang
ACS EARTH AND SPACE CHEMISTRY
(2020)
Article
Chemistry, Multidisciplinary
Yiju Liao, Alexandria Aspin, Xuan Fu, Ziming Yang
Summary: Organic reactions in hydrothermal systems play important roles in geochemically relevant processes, with the oxidation pathways of alcohols being verified in laboratory experiments. Dehydration is the dominant pathway for alcohols in the absence of dissolved metals, whereas in the presence of copper(II) or iron(III) salts, oxidation of alcohols is greatly promoted.
ACS EARTH AND SPACE CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
James D. Cope, Karizza A. Abellar, Kelvin H. Bates, Xuan Fu, Tran B. Nguyen
Summary: The research shows that aqueous oxidation of aliphatic alcohols is a strong source of small acids, resulting in underestimated atmospheric formic acid and acetic acid in models. Experimental results indicate that solution pH and OH exposure play a significant role in the production yields of formic acid and acetic acid.
ACS EARTH AND SPACE CHEMISTRY
(2021)
Article
Chemistry, Organic
Xuan Fu, Yuqin Shang, Shengxi Chen, Larisa M. Dedkova, Sidney M. Hecht
Summary: Seven D-amino acid derivatives with reactive side chains were activated to form their respective 3,5-dinitrobenzyl esters using the Mitsunobu reaction. Traditional methods involving 3,5-dinitrobenzyl chloride under alkaline conditions were found to be difficult for esterification. The conversion of tRNA to D-glutaminyl-tRNA using D-glutamine 3,5-dinitrobenzyl ester was efficiently catalyzed by a flexizyme, and the purified product was used for the incorporation of D- and L-glutamine into a model peptide related to IFN-beta.
Article
Chemistry, Multidisciplinary
Xuan Fu, Megan Jamison, Aaron M. Jubb, Yiju Liao, Alexandria Aspin, Kyle Hayes, Christopher R. Glein, Ziming Yang
CHEMICAL COMMUNICATIONS
(2020)
Review
Chemistry, Multidisciplinary
Xiaohua Liu, Haifeng Zheng, Yong Xia, Lili Lin, Xiaoming Feng
ACCOUNTS OF CHEMICAL RESEARCH
(2017)
