Article
Chemistry, Multidisciplinary
Junrui Zhou, Weilin Wang, Fenfang Zuo, Shupeng Liu, Pathan Mosim Amin, Kangbao Zhong, Ruopeng Bai, Youliang Wang
Summary: This study reports a catalyst-controlled method for the generation of alpha-carbonyl cations from alkynes and their interception via rearrangement to form unsaturated carbonyl compounds. Two chemodivergent catalytic systems were established, leading to different types of alpha-carbonyl cations and products. The method also demonstrates the fragmentation of tert-butyl groups into olefin functionalities.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Organic
Hui Xie, Jin-Yi Liang, Zhuo-Jun Huang, Bing Shu, Yi-Chuan Zheng, Yan-Zhi Liu, Shao-Yong Chen, Xu-Ge Liu, Shang-Shi Zhang
Summary: A Rh(iii)-catalyzed tandem reaction using 5-methylene-1,3-dioxan-2-one as an efficient allyl source has been developed for the synthesis of 3,4-dihydropyrimido[1,6-a]indol-1(2H)-ones, showing good substrate scope and moderate to excellent yields. The Rh(iii) catalyst plays a dual role in C-H activation and N-alkylation annulation process in the mechanism studies.
ORGANIC CHEMISTRY FRONTIERS
(2021)
Article
Chemistry, Organic
Rohit Sarthi, Rohit Kumar, Tamanna Sharma, Upendra Sharma
Summary: In this study, a concise Rh(III)-catalyzed C(sp3)-H alkylation of 8-methylquinolines with oxabenzonorbornadiene scaffolds and other strained olefins was presented. The developed catalytic methodology exhibits key features such as the retention of the oxabenzonorbornadiene skeleton, broad substrate scope, and wide-ranging functional group tolerance. Mechanistic studies revealed that the reaction proceeds through a non-radical pathway, with the five membered rhodacycle serving as the key intermediate. This is the first report on the C(sp3)-H alkylation of 8-methylquinolines with strained oxabenzonorbornadiene scaffolds (with ring retention).
Article
Chemistry, Multidisciplinary
Min Wu, Haiman Zhang, Ting Wang, Shuang Lin, Ziyang Guo, Hui Gao, Zhi Zhou, Wei Yi
Summary: In this study, the Rh(III)-catalyzed chemo-, regio-, and stereoselective carboamination of sulfonyl allenes has been achieved. This reaction utilizes N-phenoxy amides or N-enoxy imides as both C and N sources, and proceeds via a redox-neutral tandem C-H activation/allene insertion/oxidative addition/C-N bond formation pathway, enabling the direct construction of allylamine derivatives with an alpha-quaternary carbon center. The protocol demonstrates high atom-economy and good substrate compatibility, highlighting its synthetic potential for late-stage C-H modification of complex molecules.
CHEMICAL COMMUNICATIONS
(2022)
Article
Chemistry, Organic
Yichun Wang, Deyang Jia, Jing Zeng, Yuming Liu, Xiubin Bu, Xiaobo Yang
Summary: A visible-light-accelerated Rh(III)-catalyzed C-H annulation of aromatic amines with bicyclic alkenes was developed for the synthesis of benzocarbazole derivatives. The reaction proceeded smoothly at room temperature, delivering good to excellent yields of bridged oxa or aza tetrahydro benzocarbazoles. Furthermore, benzo[b]carbazoles were conveniently synthesized through further aromatization in one pot, showcasing the method's potential for various applications.
Article
Chemistry, Multidisciplinary
Anurag Singh, Rahul K. Shukla, Chandra M. R. Volla
Summary: In this study, a novel nonoxidative [5 + 1] annulation reaction was reported. By using Rh(III) catalyst, 2-alkenylanilides and allenyl acetate were selectively reacted to obtain 1,2-dihydroquinoline derivatives. The reaction involves a series of steps including activation, insertion, elimination, and cyclization, achieving the construction of compounds. The method has a wide range of applications and can be used for functionalization of natural products.
Article
Chemistry, Multidisciplinary
Shuwen Zhao, Xiaojia Cai, Yuying Lu, Jinhui Hu, Zhuang Xiong, Jingwei Jin, Yin Li, Honggen Wang, Jia-Qiang Wu
Summary: A mild, selective, and redox-neutral C-H activation/annulation reaction of salicylaldehydes with fluorovinyl tosylates is reported. The use of monofluorovinyl tosylate leads to the synthesis of C2- and C3-substitution-free chromones, while difluorovinyl tosylate results in the construction of C2-fluoroalkoxy chromones. The reaction exhibits mild conditions and good functional-group tolerance.
CHEMICAL COMMUNICATIONS
(2022)
Article
Chemistry, Physical
Yoshimi Kato, Luqing Lin, Masahiro Kojima, Tatsuhiko Yoshino, Shigeki Matsunaga
Summary: By introducing pseudo-C2 symmetric tunable chiral carboxylic acids, the study achieved enantioselective C(sp(3))-H amidation reactions of substrates such as 2-alkylpyridines, improving the chiral selectivity towards the substrates.
Article
Chemistry, Multidisciplinary
Reece H. Hoogesteger, Nicola Murdoch, David B. Cordes, Craig P. Johnston
Summary: A cobalt-catalyzed Wagner-Meerwein rearrangement of gem-disubstituted allylarenes was reported, which produced fluoroalkane products with isolated yields up to 84%. The modification of the counteranion in the N-fluoropyridinium oxidant indicated the nucleophilic fluorination of the substrates during the reaction. Other known metal-mediated hydrofluorination procedures did not result in observable 1,2-aryl migration when applied to the substrates, indicating the unique ability of these cobalt-catalyzed conditions to generate a sufficiently reactive electrophilic intermediate capable of promoting this Wagner-Meerwein rearrangement.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Organic
Yuqian Dai, Xingwei Li, Bingxian Liu
Summary: This study achieved the one-pot synthesis of cyclohexanone-isocoumarins through rhodium-catalyzed aryl C-H activation and annulation with in-situ generated iodonium ylides of cyclohexanones, with good reaction efficiency.
CHINESE JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Yi-Chuan Zheng, Bing Shu, Yao-Fu Zeng, Shao-Yong Chen, Jia-Lin Song, Yan-Zhi Liu, Lin Xiao, Xu-Ge Liu, Xuanxuan Zhang, Shang-Shi Zhang
Summary: A chemoselective synthesis of 8H-indazolo [1,2-a]cinnolines has been achieved via a cascade reaction using Cp*Ir(iii) and Cp*Rh(iii) catalysts. This strategy exhibits a broad substrate scope, high functional group compatibility, and mild reaction conditions, making it suitable for late-stage modification of drug molecules. Furthermore, a preliminary mechanistic probe has been conducted, proposing an exploratory reaction mechanism.
ORGANIC CHEMISTRY FRONTIERS
(2022)
Article
Chemistry, Organic
Anurag Singh, Arnab Dey, Chandra M. R. Volla
Summary: In the Rh(III)-catalyzed redox-neutral coupling of N-phenoxyacetamides and alkylidenecyclopropanes, diverse chemical reactions can be achieved leading to either o-dienylation of phenols or [3+2]-annulation to generate dihydrobenzofurans. The nucleophilic directing group plays a crucial role in controlling the stereoselectivity of the products, demonstrating high synthetic utility for gram scale reactions and further derivatization.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Biochemistry & Molecular Biology
Alexandra S. Bubnova, Daria V. Vorobyeva, Ivan A. Godovikov, Alexander F. Smol'yakov, Sergey N. Osipov
Summary: An efficient method for accessing CF3-containing spiro-[indene-proline] derivatives has been developed through a Cp*Rh(III)-catalyzed tandem C-H activation/[3+2]-annulation reaction between 5-aryl-2-(trifluoromethyl)-3,4-dihydro-2H-pyrrole-2-carboxylates and alkynes. Remarkably, the dehydroproline moiety acts as a directing group, enabling selective activation of aromatic C-H bond.
Article
Chemistry, Organic
Priyambada Prusty, Subramanian Jambu, Masilamani Jeganmohan
Summary: A mild, convenient, and effective Rh(III)-catalyzed site-selective C2-alkenylation of N-carboxamide indoles with unactivated alkenes at room temperature has been described. The reaction was successfully demonstrated with a variety of indole N-carboxamides and unfunctionalized/functionalized unactivated alkenes, and a possible reaction mechanism involving C-H activation/insertion/internal oxidation followed by protonation has been proposed and supported by deuterium-labeling studies.
Article
Chemistry, Applied
Liming Zhang, Ru Zhao, Chunhui Liu, Zhaoyang Li, Jun-Long Niu, Hao-Ran Yang, Lijun Gao, Shuang-Liang Liu, Liming Zhou
Summary: The Rh(III)-catalyzed ortho alkylation of N-pyridylcarbazoles with nitroalkenes has been developed for the synthesis of a wide range of 2-(2nitroalkyl)carbazoles. Aromatic and aliphatic nitroalkenes both successfully participated in this alkylation reaction. The protocol also worked well with an indoline based substrate. Derivatization of the representative nitroalkane product was described.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Article
Chemistry, Multidisciplinary
Guangying Tan, Fritz Paulus, Alessia Petti, Maxim-Aleksa Wiethoff, Anna Lauer, Constantin Daniliuc, Frank Glorius
Summary: A novel radical relay 1,4-carboimination between two distinct olefins with alkyl carboxylic acid-derived bifunctional oxime esters was achieved via energy transfer catalysis. The reaction showed high chemo- and regioselectivity, forming multiple C-C and C-N bonds in a single operation. This mild and metal-free method exhibited a broad substrate scope and excellent tolerance of sensitive functional groups, providing easy access to structurally diverse 1,4-carboiminated products. Furthermore, the obtained imines could be readily converted into valuable biologically relevant free gamma-amino acids.
Article
Chemistry, Organic
Dawod Yousif, Luca Vaghi, Constantin G. Daniliuc, Riccardo Po, Antonio Papagni, Fabio Rizzo
Summary: The regioselective nitration of 9,9'-spirobifluorene under mild conditions is reported for the first time using Menke's and Crivello's conditions. The optimized protocol yields 2-nitro and 2,2'-dinitro-9,9'-spirobifluorene in 79% and 95% yield, respectively, and for the first time, 2,2',7-trinitro-9,9'-spirobifluorene with a yield of 66%. Additionally, the role of dinitrate salt in Crivello's protocol has now been clarified, opening up new possibilities in the preparation of functional materials.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Till Drennhaus, Dirk Leifert, Jessika Lammert, Jan Philipp Drennhaus, Klaus Bergander, Constantin G. Daniliuc, Armido Studer
Summary: In this study, enantioenriched chiral indoles were synthesized through a mild and efficient radical cascade reaction using a chiral copper-bisoxazoline complex. The targeted 2-fluoroalkylated 3-(alpha-cyanobenzy-lated) indoles were accessed with excellent enantioselectivity and good yields. Mechanistic studies revealed a negative nonlinear effect which explained the stereochemical outcome. The enantioenriched 3-(alpha-cyanobenzylated) indoles demonstrated scalability and potential utility as hubs for chiral tryptamines, indole-3-acetic acid derivatives, and triarylmethanes, and a formal synthesis of a natural product analogue was disclosed.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Akash Kaithal, Himadri Sekhar Sasmal, Subhabrata Dutta, Felix Schafer, Lisa Schlichter, Frank Glorius
Summary: This study reports a catalytic approach to synthesizing cis-selective saturated carbo-and heterocyclic germanium compounds with a 3D framework through the hydrogenation of readily accessible aromatic germanes with a 2D framework. Nishimura's catalyst exhibited the best hydrogenation reactivity, achieving an isolated yield of up to 96%. The synthesized products showed versatile applications in coupling reactions and demonstrated orthogonal reactivity with boranes or silanes, acquiring a three-dimensional structure with high stability.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Roman Kleinmans, Subhabrata Dutta, Kristers Ozols, Huiling Shao, Felix Schafer, Rebecca E. Thielemann, Hok Tsun Chan, Constantin G. Daniliuc, Kendall N. Houk, Frank Glorius
Summary: The ortho-selective intermolecular photocycloaddition of bicyclic aza-arenes is reported, utilizing a strain-release approach. This reaction enables the construction of C-(sp(3))-rich bicyclo-[2.1.1]-hexanes directly connected to N-heteroarenes. Photophysical experiments and DFT calculations reveal the mechanism of this selective intermolecular photocycloaddition.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Alena I. Siutkina, Svetlana Kalinina, Rongfang Liu, Laura H. Heitman, Anna Junker, Constantin G. Daniliuc, Dmitrii V. Kalinin
Summary: We report the microwave-assisted synthesis of previously unreported 6-methoxy-5,6-dihydro-5-azapurines, which have a promising purinelike scaffold for drug discovery. The method is simple and fast, using easily accessible reagents such as trimethyl orthoformate, acetic acid, and aminotriazole-derived N,N'-disubstituted formamidines. Preliminary biological evaluation showed that the synthesized 6-methoxy-5,6-dihydro-5-azapurines dose-dependently reduce the viability of HepG2 and A549 cancer cells with little to no influence on five tested purinergic receptors.
Article
Chemistry, Multidisciplinary
Fritz Paulus, Colin Stein, Corinna Heusel, Tobias J. Stoffels, Constantin G. Daniliuc, Frank Glorius
Summary: In this study, a novel three-component 1,2,5-trifunctionalization reaction driven by visible light energy transfer-catalysis was reported. Selective installation of three different functional groups was achieved in one step by utilizing imine-based bifunctional reagents and two distinct alkenes. Mechanistic studies and downstream modifications demonstrated the synthetic utility of the obtained products.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Review
Chemistry, Multidisciplinary
Peter Bellotti, Frank Glorius
Summary: The concept of strain in organic compounds is essential for understanding the synthesis and properties of organic compounds. Recent advancements in strain-release reactions and photocatalysis have opened up new possibilities for creating unique chemical architectures and expanding the field of strain research.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Huamin Wang, Johannes E. Erchinger, Madina Lenz, Subhabrata Dutta, Constantin G. Daniliuc, Frank Glorius
Summary: This study presents a photoredox strategy that enables the high regio- and syn-selective difunctionalization of bicyclo[1.1.0]-butanes (BCBs). By cleaving C-S sigma bonds, sulfur-alkynylation, -alkenylation, and -allylation of BCBs can be achieved under mild conditions, demonstrating the generality of this approach.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Organic
Shyam Kumar Banjare, Dirk Leifert, Frauke Weidlich, Constantin G. Daniliuc, Fatmah A. Alasmary, Armido Studer
Summary: An oxidative radical cascade addition cyclization approach using eco-friendly iron catalysis and inexpensive TBHP as the oxidant has been developed for the synthesis of quinoline-based p-extended polyheterocyclic compounds. This method allows the preparation of quinolines that are p-conjugated with an additional heteroarene moiety in a single sequence.
Article
Chemistry, Multidisciplinary
Lukas Schifferer, Leon Hoppmann, Robin Groeters, Christian Mueck-Lichtenfeld, Constantin G. Daniliuc, Olga Garcia Mancheno
Summary: A solvent-dependent, divergent synthesis of highly functionalized N,S-heterocycles, containing thiazoline and isoquinuclidine or tetrahydroisoquinoline scaffolds, has been reported. This synthesis involves cyclization reactions of isoquinolinium 1,4-zwitterionic thiolates and shows robustness and applicability as demonstrated by efficient upscaling of the reaction and derivatization of the resulting products.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Till Drennhaus, Dirk Leifert, Jessika Lammert, Jan Philipp Drennhaus, Klaus Bergander, Constantin G. Daniliuc, Armido Studer
Summary: Enantioenriched chiral indoles were synthesized through a mild and efficient radical cascade reaction. The targeted indoles were accessed by stereochemical control using a chiral copper-bisoxazoline complex. The method demonstrated excellent enantioselectivity and good yields, and the mechanism was elucidated through mechanistic studies.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Angela Mesias-Salazar, Rene S. Rojas, Fernando Carrillo-Hermosilla, Javier Martinez, Antonio Antinolo, Oleksandra S. Trofymchuk, Fabiane M. Nachtigall, Leonardo S. Santos, Constantin G. Daniliuc
Summary: This study presents the synthesis and characterization of a new family of one-component catalysts based on guanidinium salts, which are used for the synthesis of cyclic carbonates. The results demonstrate that these catalysts have good conversion rates and can operate effectively at moderate pressures and temperatures.
NEW JOURNAL OF CHEMISTRY
(2023)
