Review
Chemistry, Multidisciplinary
Rosa Lopez, Claudio Palomo
Summary: This Minireview highlights the limited but significant catalytic methods for the generation of planar chirality in strained molecules, and serves as an inspiration for the development of new unconventional procedures in the future.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Organic
Eisuke Sato, Ayaka Yukiue, Koichi Mitsudo, Seiji Suga
Summary: Anodic oxidation was used to achieve the aromatization of 1,2,3,4-tetrahydrocarbazoles. Nitrogen-protected tetrahydrocarbazoles were converted to carbazoles with the use of bromide as a mediator. The presence of AcOH and the inexpensive bromide source LiBr allowed for efficient transformation.
Article
Chemistry, Physical
Jiayan Li, Changgui Zhao
Summary: Planar-chiral cyclophanes have unique properties and are important for drug discovery. However, the catalytic asymmetric synthesis of planar-chiral cyclophanes has been a challenge. We report a new reaction method for the high-yield, high-eselectivity synthesis of chiral planar cyclophanes. Through studying the reaction mechanism and enantioselectivity, we gain a deeper understanding of the process.
Article
Chemistry, Physical
Doaa R. Ramadan, Francesco Ferretti, Fabio Ragaini
Summary: This paper describes a palladium/phenanthroline catalyzed reductive cyclization of o-nitrobiphenyls to 9H-carbazoles operated by in situ released CO. The presence of phenyl formate is essential to avoid the use of high-pressure equipment and allows the reaction to be performed in a single thick-walled glass tube. The selectivity of the reaction is influenced by the identity of the base catalyzing the formate decomposition, and the stability of the catalyst is affected by the presence of chloride anions. The optimized catalytic system exhibits excellent stability and tolerance to moisture and air, enabling the reaction to be conducted with low catalyst loadings.
JOURNAL OF CATALYSIS
(2022)
Article
Chemistry, Organic
Matteo Faltracco, Said Ortega-Rosales, Elwin Janssen, Razvan C. Cioc, Christophe M. L. Vande Velde, Eelco Ruijter
Summary: The unexpected discovery in a seemingly trivial reaction led to the selective formation of a new carbazole product. This reaction, by carefully varying substituents, revealed a complex cascade mechanism with at least 10 elementary steps that could be directed towards different carbazole derivatives.
Article
Chemistry, Multidisciplinary
Ivan E. Romero, Al Postigo, Sergio M. Bonesi
Summary: This review focuses on the synthesis of carbazole derivatives using various methods, such as direct irradiation, photosensitization, photoredox, electrochemical, and thermal cyclization reactions. The methods described in this review enable efficient formation of new C-C and C-heteroatom bonds under mild conditions and allow for broad substrate diversity and functional group tolerance.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Medicinal
Milena Witkowska, Natalia Maciejewska, Malgorzata Ryczkowska, Mateusz Olszewski, Maciej Baginski, Slawomir Makowiec
Summary: Mitochondrial targeting is crucial in anticancer therapy. The synthesis of novel substituted carbazole derivatives as mitochondria-disruptive agents shows potent oxidative activity, leading to DNA damage and dysfunction of mitochondria. These findings provide new leads for the treatment of colon cancer and osteosarcoma.
EUROPEAN JOURNAL OF MEDICINAL CHEMISTRY
(2022)
Article
Chemistry, Physical
Yihao Zhou, Jinyi Dong, Qiangbin Wang
Summary: Reconfigurable chiral plasmonic complexes are created by assembling multiple individual gold nanorod dimers using DNA origami templates. Each chiral center can switch between achiral, left-handed, and right-handed states. The overall circular dichroism is determined by the coupling of individual chiral centers and is heavily influenced by the precise number and arrangement of these centers.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Manuel Weh, Jessica Ruehe, Benedikt Herbert, Ana-Maria Krause, Frank Wuerthner
Summary: The deracemization process of a racemic mixture of chiral molecules into enantioenriched compounds is achieved by an inherently chiral perylene bisimide cyclophane, which can transform [5]-helicene into an enantioenriched mixture with a high enantiomeric excess. The macrocyclic supramolecular host shows strong and enantioselective binding towards homochiral carbohelicenes, suggesting potential applications in template-catalyzed deracemization processes.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Review
Chemistry, Organic
Amanda Aline Barboza, Juliana Arantes Dantas, Mateus Oliveira Costa, Attilio Chiavegatti, Guilherme Augusto de Melo Jardim, Marco Antonio Barbosa Ferreira
Summary: This review summarizes recent advances in Pd(II)-catalyzed oxidative couplings, focusing on the use of molecular oxygen as the sole stoichiometric oxidant in these reactions.
SYNTHESIS-STUTTGART
(2022)
Article
Chemistry, Multidisciplinary
Mazen Elsaid, Robbie Ge, Chong Liu, Debabrata Maiti, Haibo Ge
Summary: This paper reports the first development of direct Pd-catalyzed C-H alkylation and acylation of carbazoles assisted by norbornene (NBE) as a transient directing mediator. The method does not require the installation of a pre-installed directing group, greatly expanding the applicability of carbazole compounds and improving reaction efficiency.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Organic
Zhidong Jiang, Jianhui Zhou, Haoran Zhu, Hong Liu, Yu Zhou
Summary: A novel Rh(III)-catalyzed C-H activation/annulation cascade of indole-enaminones with diazo compounds was reported, generating diversely functionalized carbazole frameworks with good to excellent yields. The most notable feature is the formation of a novel [5 + 1] cyclization product, accompanied by the complete removal of acetyl and N,N-dimethyl groups from the substrates, rather than the expected [4 + 2] cyclization products.
Article
Chemistry, Multidisciplinary
Zheng-Lin Wang, Yun-Hao Zhang, Jun-Yu Huang, Jian Zhou, Ya-Qin Yu, Dexin Feng, Da-Zhen Xu
Summary: The development of aerobic oxidative C-H/N-H cross-coupling catalyzed by first-row transition metals, particularly iron, is challenging but attractive. In this study, a first iron-catalyzed intramolecular cross-dehydrogenative coupling was reported for the synthesis of carbazoles and indoles using air as the oxidant. The protocol offers a general and efficient method for C-N bond formation with excellent functional group compatibility and provides a wide range of N-H carbazoles and indoles in good yields. Remarkably, all carbazoles are prepared through a C-H amination and aromatization process with the loss of 6Hs from 2-cyclohexenyl aminoarenes. Furthermore, the method also works for C-O bond formation.
Article
Chemistry, Inorganic & Nuclear
Jing Zhang, Frederic Aribot, Jean-Claude Chambron, Nathalie Zorn, Emmanuelle Leize-Wagner, Marion Jean, Nicolas Vanthuyne, Enrique Espinosa, Emmanuel Aubert
Summary: Cyclotribenzylenes (CTBs) with carbonitrile and alkyne substituents were synthesized and resolved into enantiomers using HPLC. Platinum-bridged CTB dimers were prepared from these compounds, forming Pt-alkynyl bonds in cis configuration. Mass spectrometry and NMR spectroscopy analysis revealed that racemic CTBs resulted in mixtures of diastereoisomers, while resolved CTBs allowed for the separation of enantiomerically pure complexes. The platinum complexes acted as pincer & pi;-alkynyl ligands for Cu(I) in the synthetic process, leading to the formation of mononuclear bis-cyclotribenzylene complexes by removing Cu+ cations with NaCN. However, these complexes failed to form metallo-cryptophanes, indicating the superiority of one pot self-assembly processes for their preparation.
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Guanghui Ouyang, Jessica Ruehe, Yang Zhang, Mei-Jin Lin, Minghua Liu, Frank Wuerthner
Summary: The study presents a chiral PBI hetero-cyclophane (BBI-PBI) with intramolecular energy and solvent-regulated chirality transfer from the BBI to the PBI subunit. The combination of excellent spectral overlap and spatial arrangement of BBI and PBI leads to efficient excitation energy transfer and high quantum yield PBI emission in various solvents, while chirality transfer is strongly dependent on the respective solvent. The combination of energy and chirality transfer results in bright red circularly polarized luminescence from the PBI chromophore by excitation of BBI.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Applied
Peng Wu, Jas S. Ward, Kari Rissanen, Carsten Bolm
Summary: Copper-catalyzed cross-coupling reactions of alpha-bromoaryl NH-sulfoximines with elemental sulfur were used to synthesize benzo[d][1,3,2]dithiazole-1-oxides, which belong to a new class of three-dimensional heterocycles. The reactions exhibited good functional group and heterocycle tolerance under mild conditions. Moreover, the initial cross-coupling products could be converted to unprecedented cyclic sulfonimidamides derivatives through imination/oxidation. Additionally, a seven-membered heterocycle was obtained by a ruthenium-catalyzed ring-expansion with ethyl propiolate.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Article
Chemistry, Organic
Christian Schumacher, Jas S. Ward, Kari Rissanen, Carsten Bolm, Mohamed Ramadan El Sayed Aly
Summary: Cholesterol can react under Appel conditions to form 3,5-cholestadiene and 313-bromocholest-5-ene, which deviates from the stereochemistry of the standard Appel mechanism due to the involvement of A5 pi-electrons. However, the subsequent azidolysis of 313-bromocholest-5-ene proceeds mainly by Walden inversion, resulting in the formation of 3a-azidocholest-5-ene. The structures of the products were confirmed by X-ray crystallography and the NMR data matched the reported data.
BEILSTEIN JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Rene Hommelsheim, Sandra Bausch, Arjuna Selvakumar, Mostafa M. Amer, Khai-Nghi Truong, Kari Rissanen, Carsten Bolm
Summary: Copper(I)-catalyzed domino reactions of 2-azido sulfoximines with 1-iodoalkynes afford fused triazolyl-containing benzothiadiazine-1-oxides in one step with high yields. This method exhibits broad functional group tolerance and allows the synthesis of two fused heterocyclic rings. Mechanistic investigations reveal the involvement of a copper pi-complex and an iodinated triazole intermediate in the reaction sequence.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Ettore Bartalucci, Christian Schumacher, Leeroy Hendrickx, Francesco Puccetti, Igor d'Anciaes Almeida Silva, Riza Dervisoglu, Rakesh Puttreddy, Carsten Bolm, Thomas Wiegand
Summary: Mechanical forces, including compressive stresses, have a significant impact on chemical reactions. The absence of organic solvents, synthetic acceleration, and unique reaction pathways make mechanochemical conditions advantageous. An accurate characterization of ball-milling products and a deeper mechanistic understanding of the transformations at a molecular level are critical for fully realizing the potential of organic mechanosynthesis.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Physical
Mostafa M. Amer, Rene Hommelsheim, Christian Schumacher, Deshen Kong, Carsten Bolm
Summary: An electro-mechanochemical protocol using strained BaTiO3 nanoparticles has been developed for the synthesis of vinylic sulfoximines. The catalytic active system is generated in situ by the reduction of copper(ii) chloride. The method tolerates various electron-donating and -withdrawing groups, and leads to difunctionalised double bond products in good to excellent yields. Attempts to add a sulfoximidoyl chloride to an alkyne were difficult, while additions of a sulfonyl iodide to allenes and alkynes proceeded smoothly in the presence of silica gel without needing activation by a piezoelectric material.
FARADAY DISCUSSIONS
(2023)
Editorial Material
Chemistry, Physical
Matej Balaz, Viktor Balema, Richard G. Blair, Elena Boldyreva, Carsten Bolm, Adam B. Braunschweig, Robert W. Carpick, Stephen L. Craig, Franziska Emmerling, James P. Ewen, Cecilia Fiore, Tomislav Friscic, Sven Gratz, Ivan Halasz, Ehsan Hamzehpoor, Hajime Ito, Jeung Gon Kim, Giulio Lampronti, Danielle Laurencin, James Mack, Lucia Maini, Paolo P. Mazzeo, Sharmarke Mohamed, Karthik Nagapudi, Allan Niidu, Jogirdas Vainauskas, Caterina Zuffa
FARADAY DISCUSSIONS
(2023)
Editorial Material
Chemistry, Physical
Alexander Angerhofer, Thomas Auvray, Viktor Balema, Matej Balaz, James D. Batteas, Richard G. Blair, Elena Boldyreva, Carsten Bolm, Lars Borchardt, Tristan H. Borchers, Adam B. Braunschweig, Duncan L. Browne, Robert W. Carpick, Maria Ciaccia, Stephen Craig, Franziska Emmerling, Michael Ferguson, Cecilia Fiore, Tomislav Friscic, Sven Gratz, Ivan Halasz, Ehsan Hamzehpoor, Hajime Ito, Stuart James, Jeung Gon Kim, Frederic Lamaty, Giulio Lampronti, Danielle Laurencin, Jamie Leitch, Erli Lu, Stipe Lukin, James Mack, Lucia Maini, Ashlie Martini, Paolo P. Mazzeo, Adam A. L. Michalchuk, Sebastien Mittelette, Sharmarke Mohamed, Audrey Moores, Aldo de Jesus Mortera-Carbonell, Karthik Nagapudi, Allan Niidu, Francesco Puccetti, Martin Stahorsky, Leonarda Vugrin
FARADAY DISCUSSIONS
(2023)
Editorial Material
Chemistry, Physical
Alexander Angerhofer, Matej Balaz, Viktor Balema, Ana M. Belenguer, Richard G. Blair, Elena Boldyreva, Carsten Bolm, Lars Borchardt, Adam B. Braunschweig, Duncan L. Browne, Stephen Craig, Lamis El Wenni, Franziska Emmerling, Michael Ferguson, Cecilia Fiore, Tomislav Friscic, Kimichika Fukushima, Felipe Garcia, Lori Gonnet, Sven Gratz, Rafael A. R. Hernandez, Hajime Ito, Stuart L. James, Deniz Karabiyikli, Jeung Gon Kim, Koji Kubota, Frederic Lamaty, Giulio Lampronti, Jamie Leitch, Stipe Lukin, James Mack, Lucia Maini, Sharmarke Mohamed, Audrey Moores, Karthik Nagapudi, Francesco Puccetti, Mi Tian, Qian Yu
FARADAY DISCUSSIONS
(2023)
Editorial Material
Chemistry, Physical
Matej Balaz, Viktor Balema, James D. Batteas, Richard G. Blair, Carsten Bolm, Lars Borchardt, Adam B. Braunschweig, Stephen L. Craig, Franziska Emmerling, Michael Ferguson, Tomislav Friscic, Stuart James, Jamie Leitch, James Mack, Sharmarke Mohamed, Karthik Nagapudi, Francesco Puccetti, Maria Elena Rivas
FARADAY DISCUSSIONS
(2023)
Article
Chemistry, Organic
Xianliang Wang, Kari Rissanen, Carsten Bolm
Summary: N-Trifluoroacetylated (N-TFA) sulfoximines react with 1-trifluoromethylstyrenes in a one-pot domino reaction to give fluorinated 5,6-dihydro-1,2-thiazine 1-oxides in good to high yields. The process involves three sequential reaction steps that can be characterized as (1) nucleophilic allylic substitution (S(N)2 '), (2) hydrolysis, and (3) intramolecular nucleophilic vinylic substitution (SNV). The products can further be modified by defluorination. The molecular structure of the resulting product was confirmed by X-ray crystallographic analysis.
Article
Chemistry, Multidisciplinary
Pit van Bonn, Jinbo Ke, Christopher Weike, Jas S. Ward, Kari Rissanen, Carsten Bolm
Summary: Difluoromethyl ethers are obtained through mechanochemical reactions between alcohols and difluorocarbene in a mixer mill. The method is applicable to primary, secondary, and tertiary alcohols, yielding the corresponding products with excellent yields (up to 99%) after 1 hour at room temperature. The reactions take place under solvent-free conditions and the products are purified by filtration, resulting in significantly reduced waste generation.
Article
Chemistry, Physical
Ettore Bartalucci, Dominique J. Luder, Nicole Terefenko, Alexander A. Malaer, Carsten Bolm, Matthias Ernst, Thomas Wiegand
Summary: Fast MAS NMR experiments have been used to study a wide range of materials, including biomolecules and pharmaceuticals, and proton-spin diffusion (SD) plays a crucial role in resonance assignment and structure determination. Negative cross peaks in 2D SD-based spectra have been observed in small organic molecules with methyl groups, which can be attributed to higher-order coherent contributions dominating the observed negative peaks. The presence of low-frequency shifted H-1 resonances in methyl groups prevents sizeable second-order spin-diffusion processes, masking the negative contribution to the peaks.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Rene Hommelsheim, Sandra Bausch, Robin van Nahl, Jas S. Ward, Kari Rissanen, Carsten Bolm
Summary: A variety of 3-amino-substituted benzothiadiazine oxides were synthesized via a one-step palladium-catalyzed cascade reaction of 2-azido sulfoximines with isonitriles. The desired heterocycles were obtained in good to excellent yields using very low catalyst loadings and short reaction times. This protocol provides direct access to precursors for pharmaceutically relevant sulfoximines.
Article
Hematology
Edouard Lansiaux, Emmanuel Drouin, Carsten Bolm
Summary: Through screening three databases, researchers found that beta-thalassemia carriers may be less affected by COVID-19 than the general population, but they are more likely to experience severe symptoms, have a lower ICU admission rate, and have a higher risk of death. However, these results are not statistically significant, and further large case-control or registry studies are needed to confirm these trends.
THALASSEMIA REPORTS
(2023)
Article
Chemistry, Organic
Carsten Bolm, Xianliang Wang, Kari Rissanen
Summary: N-Trifluoroacetylated sulfoximines react with 1-trifluoromethylstyrenes in a one-pot domino reaction to give fluorinated 5,6-dihydro-1,2-thiazine 1-oxides in good to high yields. The reaction involves nucleophilic allylic substitution, hydrolysis, and intramolecular nucleophilic vinylic substitution. The resulting product's molecular structure was confirmed by X-ray crystallographic analysis.
