Article
Chemistry, Inorganic & Nuclear
Kristina Zivkovic, Lilia M. Baldauf, Jessica L. Cryder, Alexa Villasenor, Valeria Reyes, Lauren E. Bernier, Theresa J. Thomas, Maxwell O'Toole, Kayleen Fulton, Curtis E. Moore, Arnold L. Rheingold, Christopher J. A. Daley
Summary: The study reports the first isolation and structural characterization of a series of chiral trinitrogen pincer ligands, as well as the methods for their preparation. Experimental results show that a novel microwave-based technique is more efficient, although currently not scalable.
DALTON TRANSACTIONS
(2021)
Article
Chemistry, Organic
Luca Vaghi, Roberto Cirilli, Marco Pierini, Simona Rizzo, Giancarlo Terraneo, Tiziana Benincori
Summary: PHANE-TetraPHOS, a novel D-2 symmetric tetraphosphane, features four homotopic diphenylphosphane groups with indistinguishable spatial arrangement. Enantiomeric purity was achieved through crystallization and alkaline treatment, leading to enantiopure PHANE-TetraPHOS antipodes. These ligands showed comparable catalytic activity and enantiodiscrimination ability to PHANEPHOS, using only half the amount of chiral ligand.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2021)
Review
Chemistry, Organic
Dezheng Xie, Ziyi Chen, Chun-Jiang Wang, Xiu-Qin Dong
Summary: Phosphonates and derivatives with an α-chiral center are important compounds found in natural products, pharmaceuticals, and agrochemicals. The synthesis of these compounds has been the focus of recent research, with advancements in asymmetric catalysis such as hydrogenation, addition reactions, and nucleophilic additions to α,β-unsaturated phosphonates. The continuous development of enantioselective catalytic methods and the future applications of these compounds are also discussed.
SYNTHESIS-STUTTGART
(2023)
Article
Chemistry, Physical
Ricardo Molina Betancourt, Lucas Bacheley, Anzhela Karapetyan, Gerard Guillamot, Phannarath Phansavath, Virginie Ratovelomanana-Vidal
Summary: The Rh(III)-catalyzed asymmetric reduction of alpha-trifluoromethyl ketones through transfer hydrogenation was developed under mild conditions. It enables a dynamic kinetic resolution process to access a series of enantioenriched cis-trifluoromethyl alcohols. The reaction was performed efficiently in the green solvent 2-MeTHF using HCO2H/Et3N (1 : 1) as the hydrogen source. High yields and excellent diastereo- and enantioselectivities were achieved for the synthesis of CF3-chromanol, CF3-indanol, and CF3-tetralol derivatives.
Article
Chemistry, Multidisciplinary
Marc Strohmann, Andreas J. Vorholt, Walter Leitner
Summary: This study presents a method for transforming olefins into branched amines by combining hydroformylation/aldol condensation tandem reaction with reductive amination. The method utilizes a combined multiphase system that can be recycled 9 times. The study demonstrates the feasibility of the method and its potential applications in the production of surfactants.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Chemistry, Organic
Barbara Mohar, Marko Jeran, Michel Stephan
Summary: Outfitting the 2MeBigFUS ligand with the branched/functionalized-alkoxy feature of the R-SMS-Phos design resulted in the 2RBigFUS family. Rhodium(I) complexes of these ligands exhibited enhanced activity and superior enantioselectivity in the hydrogenation of functionalized olefins, including challenging α-arylacrylic acids. The application of these catalysts to enantiomeric active pharmaceutical ingredients (APIs) and synthetic building blocks further highlighted their potential.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Qiwei Lang, Huaxin Yang, Guoxian Gu, Qiang Feng, Jialin Wen, Xumu Zhang
Summary: In this study, an efficient method for reducing endocyclic enones with high enantioselectivity using molecular hydrogen catalyzed by a rhodium/Zhaophos complex is reported. This method demonstrated excellent chemo- and enantioselectivity and was successfully applied in the enantioselective hydrogenation of citral to produce enantiomer-enriched citronellal.
CHINESE JOURNAL OF CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Yulin Han, Anni Qin, Qian Zhang, Xue Zhang, Hui Qian, Shengming Ma
Summary: The Rh-catalyzed reaction allows for the efficient synthesis of cis-fused bicyclic products with excellent selectivity and tolerance towards synthetically useful functional groups. The proposed mechanism involves the rapid racemization of the allene moiety in the starting materials.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Inorganic & Nuclear
Nora Jannsen, Christian Fischer, Carmen Selle, Cornelia Pribbenow, Hans-Joachim Drexler, Fabian Reiss, Torsten Beweries, Detlef Heller
Summary: In this study, we systematically investigate and quantify the influence of solvent coordination on reactions of cationic rhodium(i) diphosphine complexes. We propose a method to analyze and quantify solvent binding using MeCN as a replacement for diolefins. By using UV-vis and P-31{H-1} NMR spectroscopy, we determine and compare stability constants of different complexes, and discuss the impact of different ligands and reaction temperature. DFT study reveals the relationship between stability and thermodynamics of the exchange reaction. Additionally, variable temperature NMR spectroscopy confirms the existence of a mixed solvate complex as an intermediate in the MeCN-MeOH exchange.
DALTON TRANSACTIONS
(2022)
Article
Chemistry, Multidisciplinary
Anand B. Shabade, Dipesh M. Sharma, Priyam Bajpai, Rajesh G. Gonnade, Kumar Vanka, Benudhar Punji
Summary: Chemoselective hydrogenation of C=C, C=O and C=N bonds in alpha,beta-unsaturated ketones, aldehydes and imines can be achieved at room temperature using a well-defined Mn(I) catalyst and hydrogen gas. The method shows tolerance towards various sensitive functional groups and can be applied to unsaturated ketones containing indole, pyrrole, furan, thiophene, and pyridine moieties. In the reaction, the C=C bond is selectively hydrogenated, while the C=O and C=N bonds in aldehydes and imines are preferentially reduced.
Article
Chemistry, Multidisciplinary
Mingxin Liu, Nguyen Le, Christopher Uyeda
Summary: Nickel catalysts promote nucleophilic cyclopropanation reactions using CH2Cl2 as a methylene source and Mn as a stoichiometric reductant. The substrate scope includes a broad range of alkenes bearing electron-withdrawing substituents, and enantioselective cyclopropanations have been developed using chiral PyBox ligands. Mechanistic studies suggest the intermediacy of a (PyBox)Ni=CH2 species and DFT models provide a rationale for the nucleophilic character of the nickel carbene and the sense of enantioinduction.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Organic
Chao Dong, Dao-Sheng Liu, Lei Zhang, Xiang-Ping Hu
Summary: An enantioselective Rh-catalyzed hydrogenation of E/Z mixtures of trisubstituted vinyl esters has been achieved using a chiral ferrocenylphosphine-phosphoramidite ligand. The reaction showed high yields and good to high enantioselectivities, with the presence of a small amount of t-butanol benefiting the hydrogenation outcome.
TETRAHEDRON LETTERS
(2021)
Review
Chemistry, Multidisciplinary
Johannes Grosskopf, Thorsten Bach
Summary: Upon irradiation with a suitable chiral catalyst, racemic compounds can be converted into enantiopure compounds through a process called photochemical deracemization. This review comprehensively covers the research and current developments in this field, discussing the reactions and mechanistic details underlying the presented reaction. Photochemical deracemization offers a unique opportunity to directly obtain enantiopure compounds from racemates, and short-lived intermediates play a key role in determining the enantioselectivity.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Ken-Loon Choo, Bijan Mirabi, Karl Z. Demmans, Mark Lautens
Summary: Enantioenriched spiro-oxiranes with three contiguous stereocenters were synthesized using a rhodium-catalyzed cascade reaction, enabling the formation of a spirocyclic framework in a single step. Both sp(2)- and sp-hybridized carbon nucleophiles were found to be efficient initiators, yielding products with different functional groups. Derivatization studies demonstrated the synthetic versatility of the products' epoxide and alkyne moieties. DFT calculations were employed to explain spectroscopic discrepancies between solution- and solid-state structures of the products.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Josep Mas-Rosello, Christopher J. Cope, Eric Tan, Benjamin Pinson, Alan Robinson, Tomas Smejkal, Nicolai Cramer
Summary: Cyclometalated cyclopentadienyl iridium(III) complexes are efficient catalysts in the hydrogenation of oximes, with alkoxy-substituted aryl ketimine ligands providing the best catalytic performance. The stable iridium C,N-chelation is crucial for the catalytic activity, and the hydrogenation system demonstrates high functional group compatibility.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Biochemical Research Methods
Cheryl Frankfater, Hideji Fujiwara, Spencer J. Williams, Adriaan Minnaard, Fong-Fu Hsu
Summary: This study used high-resolution mass spectrometry to investigate the mechanisms of complex mycolic acid synthesis in Mycobacterium tuberculosis cells. By characterizing the Mtb mycolic acid family, the study identified the composition and location of functional groups in different lipid species. The findings demonstrate the capability of LIT MSn in determining the structures of complex lipids in a mixture.
JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY
(2022)
Article
Chemistry, Organic
Daan V. Bunt, Sahar El Aidy, Adriaan J. Minnaard
Summary: The meroterpenoids fornicin A, fornicin D, and ganodercin D found in mushrooms of the Ganoderma genus were synthesized through a concise and divergent route. The unsaturated gamma-ketoacid moiety was obtained via an optimized step-wise aldol condensation. Additionally, a protocol for THP-protection of a phenolic hydroxyl group under basic conditions was developed, adding to the versatility of this protecting group.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Cornelis H. M. van der Loo, Rutger Schim van der Loeff, Avelino Martin, Pilar Gomez-Sal, Mark L. G. Borst, Kees Pouwer, Adriaan J. J. Minnaard
Summary: Furans derived from carbohydrate feedstocks have been widely used to produce 7-oxanorbornenes through Diels-Alder reactions. However, due to their substitution patterns, these furans typically lead to racemates. In this study, we introduce an enantiopure glucosamine derived furan that selectively yields the exo-product with a high pi-face selectivity of 6.5:1. The structure of the product has been confirmed by X-ray crystallography, and a large-scale synthesis (2.8 g, 58% yield) demonstrates the easy accessibility of this multifunctional enantiopure building block.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)
Article
Chemistry, Physical
Martin D. Witte, Sebastian B. Beil, Adriaan J. Minnaard, Marios Kidonakis, Augustin Villotet
Summary: Quinuclidine-mediated electrochemical oxidation provides a versatile and selective method for synthesizing C3-ketosaccharides with high yields, which is complementary to Pd-catalyzed or photochemical oxidation and different from the electrochemical oxidation of methylene and methine groups as it does not require oxygen.
Article
Chemistry, Multidisciplinary
Nittert Marinus, Niek N. H. M. Eisink, Niels R. M. Reintjens, Renger S. Dijkstra, Remco W. A. Havenith, Adriaan J. Minnaard, Martin D. Witte
Summary: A predictive model is developed to determine the site-selectivity in the mono-oxidation of diols using palladium-neocuproine catalysis. The model considers factors such as electronegative substituents and configuration/conformational freedom to predict the reaction rate and site-selectivity. Experimental and computational studies have validated the model, which can be used for the synthesis of complex natural products.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Organic
Maryam Ahmadian-Moghaddam, Niels R. M. Reintjens, Martin D. D. Witte, Adriaan J. J. Minnaard
Summary: A reliable method for introducing a fused methylene tetrahydrofuran ring into carbohydrates is disclosed. The resulting bicyclic saccharides can serve as scaffolds in medicinal chemistry and drug design. Furthermore, the enol ether functionality allows for modification in biological systems via photoclick chemistry. The method involves the regioselective oxidation of the C-3 hydroxy group in gluco-configured pyranosides, followed by stereoselective indium-mediated allylation. The formation of the ring is induced by an iodocyclization reaction with a neighboring hydroxy group, and subsequent dehydrohalogenation produces the desired methylene-tetrahydrofuran-containing carbohydrates.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Multidisciplinary Sciences
Thomas A. Verschut, Renny Ng, Nicolas P. Doubovetzky, Guillaume Le Calvez, Jan L. Sneep, Adriaan J. Minnaard, Chih-Ying Su, Mikael A. Carlsson, Bregje Wertheim, Jean-Christophe Billeter
Summary: Female fruit flies can assess the social information of their oviposition sites by detecting the concentration of pheromones left by previous visitors. They prefer sites with intermediate pheromone concentrations and avoid sites with low or high concentrations. This decision-making process is based on the detection of two different pheromones.
NATURE COMMUNICATIONS
(2023)
Article
Biochemistry & Molecular Biology
Shouxiong Huang, Adam Shahine, Tan-Yun Cheng, Yi-Ling Chen, Soo Weei Ng, Gautham R. Balaji, Rachel Farquhar, Stephanie Gras, Clare S. Hardman, John D. Altman, Nabil Tahiri, Adriaan J. Minnaard, Graham S. Ogg, Jacob A. Mayfield, Jamie Rossjohn, D. Branch Moody
Summary: The study identified the lipid profiles of four human CD1 antigen-presenting molecules, revealing a broad presentation of self-sphingolipids and phospholipids. Each type of CD1 protein displayed distinct capture motifs based on lipid length and chemical composition.
Article
Chemistry, Organic
Niels R. M. Reintjens, Imke M. A. Bartels, Nittert Marinus, Sarina C. Massmann, Daan V. Bunt, Marthe T. C. Walvoort, Martin D. Witte, Adriaan J. Minnaard
Summary: This study reports a simplified protocol for the selective oxidation of unprotected carbohydrates using a palladium catalyst. The reaction protocol offers a more convenient method with simplified steps and product isolation, and can be applied to a variety of sugar compounds.
Article
Chemistry, Multidisciplinary
Shigenari Ishizuka, J. Hessel M. van Dijk, Tomomi Kawakita, Yuji Miyamoto, Yumi Maeda, Masamichi Goto, Guillaume Le Calvez, L. Melanie Groot, Martin D. Witte, Adriaan J. Minnaard, Gijsbert A. van der Marel, Manabu Ato, Masamichi Nagae, Jeroen D. C. Codee, Sho Yamasaki
Summary: Although leprosy is an ancient disease, the mechanism of pathogenicity of Mycobacterium leprae is not fully understood. In this study, the researchers identified phenolic glycolipid-III (PGL-III) as a specific ligand for the immune receptor Mincle. PGL-III was found to be a more potent ligand than trehalose dimycolate, a well-known ligand from Mycobacterium tuberculosis. The study also revealed the unique recognition mode of Mincle and its interaction with multiple Mincle molecules. The findings suggest that PGL-III triggers protective immunity against M. leprae.
ACS CENTRAL SCIENCE
(2023)
Article
Chemistry, Organic
Niels R. M. Reintjens, Martin D. Witte, Adriaan J. Minnaard
Summary: Thioglycosides or S-linked-glycosides are important glycomimetics that can be synthesized by glycosylating deoxythio sugar acceptors. A carbonyl group formed by site-selective oxidation of unprotected saccharides can be converted into a thiol moiety, allowing for the preparation of deoxythio sugars through S(N)1 substitution reactions. The combination of these deoxythio sugars with protecting group-free glycosylation of glycosyl fluorides enables a protecting group-free synthesis of thioglycosides.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)
Article
Medicine, Research & Experimental
Melissa Bedard, Sanne van der Niet, Elliott M. Bernard, Gregory Babunovic, Tan-Yun Cheng, Beren Aylan, Anita E. Grootemaat, Sahadevan Raman, Laure Botella, Eri Ishikawa, Mary P. O'Sullivan, Jacob A. Mayfield, Seonadh O'Leary, Jeffrey Buter, Adriaan J. Minnaard, Sarah M. Fortune, Leon O. Murphy, Daniel S. Ory, Joseph Keane, Sho Yamasaki, Maximiliano G. Gutierrez, Nicole van der Wel, D. Branch Moody
Summary: Induction of lipid-laden foamy macrophages is a characteristic of tuberculosis (TB) and is caused by a terpenyl nucleoside shed from Mycobacterium tuberculosis. This shed nucleoside, known as 1-tuberculosinyladenosine (1-TbAd), blocks lysosomal maturation and autophagy, leading to lipid storage in M1 macrophages. Furthermore, 1-TbAd induces the storage of specific lipids and promotes the growth of M. tuberculosis, as well as mimicking the lipid storage patterns found in lysosomal storage diseases such as Gaucher's disease and Wolman's disease.
JOURNAL OF CLINICAL INVESTIGATION
(2023)
Article
Chemistry, Organic
Cornelis H. M. van der Loo, J. P. Kaniraj, Ting Wang, J. O. P. Broekman, Mark L. G. Borst, Kees Pouwer, Andre Heeres, Peter J. Deuss, Adriaan J. Minnaard
Summary: The study investigates the synthesis of nitrogen-containing aromatics through a Diels-Alder/aromatization cascade reaction using chitin-based furans. The results demonstrate that chitin-based 3-acetamido-furfural can be converted into di- and tri-substituted anilides with good to high yields via a hydrazone mediated reaction sequence.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)
Article
Chemistry, Physical
Martin D. Witte, Adriaan J. Minnaard
Summary: Oligosaccharides, either on their own or as part of other compounds, are widely present in nature and play important roles in biology, medicine, and materials science. Modifying their structure and introducing reactive and reporter groups is crucial for studying their function. Recent progress has been made in developing selective and late-stage modification methods for oligosaccharides, particularly in catalysis research.
Article
Chemistry, Organic
Ruben L. H. Andringa, Marijn Jonker, Adriaan J. Minnaard
Summary: Using a CoIII(salen)OTs catalyst, dibenzyl phosphate can selectively open a variety of terminal epoxides with high regio-selectivity and yields up to 85%. This reaction enables the efficient synthesis of enantiopure mixed-diacyl phosphatidic acids, including a photoswitchable phosphatidic acid mimic.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2022)
