Article
Chemistry, Multidisciplinary
Matthias Peeters, Jonathan Decaens, Alois Fuerstner
Summary: Chiral [BiRh]-paddlewheel complexes empowered by London dispersion enable the generation of (trifluoromethyl)furfurylidene metal complexes from a bench-stable triftosylhydrazone precursor. These complexes undergo asymmetric [2+1] cycloadditions, providing optically active trifluoromethylated cyclopropane or -cyclopropene derivatives, which are important building blocks for medicinal chemistry and difficult to obtain in optically active form.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Na Luo, Yu-Fei Ao, De-Xian Wang, Qi-Qiang Wang
Summary: The article briefly reviews the emergence and development of anion-pi interactions, emphasizing the concept of anion-pi catalysis and key progress in this area. The content is organized based on the role of anion-pi interactions in catalysis, from ground-state and transition-state stabilization to cooperative pi-face activation. A concluding remark and outlook on future development are also provided.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Biochemistry & Molecular Biology
Zita Szabo, Sophia Ben Ahmed, Zoltan Nagy, Attila Paczal, Andras Kotschy
Summary: The formation of polysubstituted cyclopropane derivatives in the gold(I)-catalyzed reaction of olefins and propargylic esters is of significant interest due to its potential usefulness in generating diversity. We tested a series of chiral gold(I)-carbene complexes as catalysts and achieved high enantioselectivity in the test reaction. However, the cis:trans selectivity of the transformation was independent of the catalyst. Although the reactions proceeded smoothly, the observed enantioselectivity varied greatly and a structure-property relationship could not be established.
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
Elisabetta Ronchi, Shauna M. Paradine, Eric N. Jacobsen
Summary: This study presents a one-step catalytic, enantioselective method for preparing homoallylic N-Boc amines directly from acetals. The generation of reactive iminium ion intermediates and subsequent allylation are favored over the formation of homoallylic ether byproducts. The experimental and computational data support the anchoring hydrogen-bond interaction and specific noncovalent interactions with the catalyst in the enantiodetermining transition state.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Multidisciplinary
Yu Nie, Jing Li, Qianjia Yuan, Wanbin Zhang
Summary: In this work, we developed an iridium-catalyzed asymmetric hydrogenation of hydantoin and thiazolidinedione derived exocyclic alkenes using BiphPHOX as a ligand. The reaction showed excellent functional group tolerance and provided the hydrogenated products with high yields and enantioselectivities. Moreover, the hydrogenated product can be efficiently transformed into an intermediate for the synthesis of a HIV protease inhibitor.
CHINESE JOURNAL OF CHEMISTRY
(2022)
Review
Chemistry, Organic
Estibaliz Sansinenea, Aurelio Ortiz
Summary: The cyclopropane structure has attracted attention in multiple investigations due to its prevalence in various natural products. It exhibits unique reactivity, particularly in 1,1-cyclopropanedicarboxylate compounds, which act as acceptor-donor cyclopropanes. Various methods have been developed to achieve cyclopropanes, including the Simmons-Smith reaction, diazoalkanes decomposition, and Michael-Initiated ring closure (MIRC). The asymmetric organocatalytic synthesis of cyclopropanes, using the MIRC method, has been successfully applied without the need for metal catalysts. This review presents different asymmetric organocatalytic syntheses of cyclopropanes from the last two decades until 2021.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Ju-Song Yang, Ka Lu, Chen-Xiao Li, Zu-Hang Zhao, Xiao-Ming Zhang, Fu-Min Zhang, Yong-Qiang Tu
Summary: Novel asymmetric mono- and dialkylation reactions of α-substituted 2,5-diketopiperazines catalyzed by new chiral spirocyclic-amide-derived triazolium organocatalysts have been developed, leading to enantioenriched products and providing a new synthetic approach.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Hou-Lu Liu, Xinyu Wang, Ke Gao, Zhaobin Wang
Summary: In this paper, we report a novel chromium-catalyzed asymmetric cyclopropanation reaction using readily available gem-dihaloalkanes and terminal olefins as precursors. This method provides diverse functionalized chiral cyclopropanes. Mechanistic studies reveal a radical-polar crossover process in this catalytic reaction.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Valentina Pelliccioli, Thierry Hartung, Martin Simon, Christopher Golz, Emanuela Licandro, Silvia Cauteruccio, Manuel Alcarazo
Summary: The study reports a highly enantioselective synthesis of 5,13-disubstituted dibenzo[d,d']benzo[1,2-b:4,3-b']dithiophenes, with the last two successive Au-catalyzed intra-molecular alkyne hydroarylation events being crucial for the successful assembly of these helical architectures.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Wanlong Xiao, Lichao Ning, Shuang Xin, Shunxi Dong, Xiaohua Liu, Xiaoming Feng
Summary: An efficient catalytic asymmetric [2+2] cycloaddition of allenyl imide and mono- or disubstituted alkenes has been developed. The use of chiral magnesium(II) complex of N,N'-dioxide allows for high yield and excellent enantioselectivity of axially chiral cyclobutenes and four-membered ring-containing spirocycles. This methodology can also be applied for the late-stage modification of biologically active molecules.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Physical
Ouidad Lahtigui, Dan Forster, Coralie Duchemin, Nicolai Cramer
Summary: In this study, a flexible two-step protocol for the efficient and selective synthesis of rigid saturated nitrogen-containing scaffolds was disclosed. The method involves alkenyl C-H functionalization and cyclization reactions mediated by C*Rh-III and Cp*Ir-III catalysts, respectively, leading to the synthesis of diverse substituted 3-azabicyclo[3.1.0]hexanes.
Article
Chemistry, Organic
Jiupeng Liu, Shuo Tang, Huayan Xu, Ruoyu Zhang, Jingjing Zhao, Puyu Zhang, Pan Li
Summary: A visible-light photocatalytic regioselective [2 + 2 + 1] radical annulation reaction of alkenes, tert-butyl nitrite, and gemdihalides has been developed, providing an efficient and practical approach to obtain isoxazolines in good yields under mild conditions. Gem-dihalides serve as C1 synthons, while cheap tert-butyl nitrite acts as an ideal N-O synthon.
Article
Chemistry, Organic
Istvan Orban, Bertalan Varga, Peter Bagi, Tamas Holczbauer, Zsolt Rapi
Summary: Enantioenriched, highly functionalized cyclopropane derivatives with complete diastereoselectivity and up to 87% enantioselectivity were prepared using monosaccharide-based chiral crown ethers as phase transfer catalysts. Among the catalysts tested, the monoaza-15-crown-5 lariat ether with a methyl beta-D-glucopyranoside unit and a 2-(3,4-dimethoxyphenyl)ethyl group on the nitrogen exhibited the highest asymmetric induction.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Na Luo, Yu-Fei Ao, De-Xian Wang, Qi-Qiang Wang
Summary: Exploring the use of anion-pi interactions in catalyst design is an exciting direction for developing new and fundamental catalysis. By establishing cooperative pi-face activation, efficient transformation and excellent selectivity control can be achieved. The supramolecular pi-catalysis strategy demonstrated in this study showcases the successful harnessing of cooperative anion-pi interactions for efficient activation and outstanding selectivity control.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Review
Chemistry, Organic
Amina Moutayakine, Anthony J. Burke
Summary: In this review, we discuss the recent advances in the synthesis of medicinally relevant oxygen benzofused heterocycles through the palladium and copper catalyzed C-X activation of haloarene precursors. This transformation has demonstrated remarkable versatility and efficiency, allowing for the construction of diverse scaffolds in a cost-effective manner. The haloarene motif, due to its availability and low cost, has emerged as an exceptional candidate for catalytic reactions leading to medicinally important targets.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Anthony J. Burke, Hans-Jurgen Federsel, Gesine J. Hermann
Summary: Transition-metal-catalyzed asymmetric reactions play an important role in organic synthesis. The design of suitable chiral ligands is crucial for achieving high stereoselectivity and high yields. Recent advancements in rigid C-stereogenic chiral phosphine ligands have greatly contributed to asymmetric transformations.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Carolina S. Marques, Oscar Lopez, Luisa Leitzbach, Jose G. Fernandez-Bolanos, Holger Stark, Anthony J. Burke
SYNTHESIS-STUTTGART
(2022)
Article
Chemistry, Inorganic & Nuclear
Alexandre C. Oliveira, Hugo A. . L. Filipe, Joao P. Prates Ramalho, Armindo Salvador, Carlos F. G. C. Geraldes, Maria Joao Moreno, Luis M. S. Loura
Summary: The correct parametrization of lanthanide complexes is crucial for their characterization using computational tools, and this study establishes the best strategies for parametrization and demonstrates the successful capture of dynamic properties.
INORGANIC CHEMISTRY
(2022)
Article
Chemistry, Physical
Michael Lalanne-Tisne, Audrey Favrelle-Huret, Wim Thielemans, Joao P. Prates Ramalho, Philippe Zinck
Summary: Organocatalysts are important in polymerization reactions. This study used Density Functional Theory to investigate the ring-opening polymerization of trimethylene carbonate, revealing a dual mechanism and confirming TBD as a more efficient catalyst.
Article
Chemistry, Multidisciplinary
Carolina S. Marques, Aday Gonzalez-Bakker, Jose M. Padron, Anthony J. Burke
Summary: An amide bond is a crucial functional motif in chemistry and biology, present in numerous biological structures and of great synthetic interest. Small-molecule amides serve as important scaffolds for drug design. This study presents a novel Ugi4CR approach for the synthesis of a library of Ugi-derived isatin-peptoids using 5-amino-3,3-protected-oxindole derivatives, carboxylic acids (and nitrophenols), aldehydes (and ketones), and isocyanides. The reaction process is one-step, clean, fast, and sustainable, with moderate to excellent yields. The library was evaluated against human solid tumor cell lines, providing preliminary structure-activity relationships. The most active derivative exhibited GI(50) values ranging from 0.06 to 2.3 μM.
NEW JOURNAL OF CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Marina Costa, Elisabete P. Carreiro, Cesar M. C. Filho, Mara Silva, Isabel Goncalves, Esmar F. Souza, Antonio P. S. Teixeira, Alexandre Craveiro, Anthony J. Burke
Summary: In this research, silver nanoparticles (AgNPs) were synthesized using various chitosan salts as stabilizing agents, which effectively prevented nanoparticle aggregation. Different chitosan salts were formed using organic acids such as acetic, succinic, formic, propionic, malic, glycolic, and lactic acid, providing a sustainable and economical method for AgNPs synthesis. Characterization techniques including UV-VIS, ATR-FTIR spectroscopy, DLS, and TEM were used to analyze the AgNPs-chitosan salts samples. Most organic acids resulted in small-sized nanoparticles (30-52 nm) with positive zeta potential. However, the use of salts of alpha-hydroxyacids and diacids, such as glycolate and succinate, led to larger particles. Stability studies revealed that storage at cold temperatures enhanced the stability of the silver nanoparticles.
Article
Thermodynamics
Felisberto S. Mendes, Carlos E. M. Cruz, Rafaela N. Martins, Joao P. Prates Ramalho, Luis F. G. Martins
Summary: This study investigated the solute-solvent interaction and mobility in aqueous solutions of two non-steroidal anti-inflammatory drugs (ketoprofen and ibuprofen) by measuring their mutual diffusion coefficients using the Taylor dispersion method. Molecular dynamics simulations were also conducted to calculate the intra-diffusion coefficients of the solutes. The results showed that ibuprofen had a higher mutual diffusion coefficient in water than ketoprofen, and the simulations were able to accurately predict the experimental values.
JOURNAL OF CHEMICAL THERMODYNAMICS
(2023)
Article
Biochemistry & Molecular Biology
Raquel Eustaquio, Joao P. Prates Ramalho, Ana Teresa Caldeira, Antonio Pereira
Summary: Fluorescent labels are crucial in various scientific applications, and this study introduces four promising and inexpensive coumarin derivatives as fluorescent labels for biomolecules.
Article
Biochemistry & Molecular Biology
Margarida M. Cordeiro, Hugo A. L. Filipe, Patricia dos Santos, Jaime Samelo, Joao P. Prates Ramalho, Luis M. S. Loura, Maria J. Moreno
Summary: In this study, the interaction between H33342 and lipid bilayers was investigated using both experimental and computational approaches. The results showed that the partition coefficient of H33342 did not vary significantly over a wide pH range. This highlights the importance of considering the association with lipid bilayers when predicting the affinity for biomembranes.
Article
Chemistry, Organic
Daniela P. Fonseca, Ana C. Amorim, Elisabete P. Carreiro, Joao P. Prates Ramalho, Gesine J. Hermann, Hans-Juergen Federsel, Ana Rita C. Duarte, Anthony J. Burke
Summary: The organocatalyst cinchonidine-squaramide was immobilized within three different deep eutectic solvents (DESs) and evaluated in an asymmetric Michael addition reaction. The results showed excellent yields (up to 99%) and enantioselectivities (up to 98%) using only 1 mol% of organocatalyst. The high recyclability of this system was demonstrated with 9 cycles using DES (betaine:D-sorbitol:water), and 5 cycles were achieved with only 0.5 mol% of organocatalyst, obtaining products with high yields (up to 95%) and excellent enantioselectivities (up to 94%).
Article
Biochemistry & Molecular Biology
Elisabete P. Carreiro, Ana R. Costa, Celia M. Antunes, Sofia Ernesto, Flavia Pinto, Beatriz Rodrigues, Anthony J. Burke
Summary: The number of patients with Alzheimer's disease (AD) is increasing with no effective treatments available. This study evaluated a library of quercetin-1,2,3-triazole hybrids for their antioxidant, oxidative stress protection, and cholinesterase inhibitory activities. Several hybrids showed promising results as multifunctional ligands in AD pathologies.
Article
Biochemistry & Molecular Biology
Natalia Busto, Joana Leitao-Castro, Alfonso T. Garcia-Sosa, Francisco Cadete, Carolina S. Marques, Renata Freitas, Anthony J. Burke
Summary: Molecular hybridization approaches have been used to develop a series of novel N-1,2,3-triazole-isatin hybrids, which show promising anti-proliferative activity against tumor cells. The compounds outperformed cis-platin in terms of anti-proliferation, and potential biological targets, including histone acetyltransferase P-300 and acyl-protein thioesterase 2, were identified. These compounds exhibit advantageous pharmacological properties and affect transcriptional regulation in oncological contexts.
RSC MEDICINAL CHEMISTRY
(2022)
Article
Chemistry, Organic
Fuying Zhu, Yamei Lin
Summary: In this study, a low-metal iron-supported catalyst (Fe20/NC-Mg) was reported for the efficient synthesis of quinoxaline compounds, using water as a solvent and without additional bases. The synergistic effect of FeNx site and Mg (OH)2 nanorods in the catalyst played a key role in achieving high yields (82-91%) in 16 examples. The gram-level synthesis and reusability of the catalysts after four cycles demonstrated its industrial application potential.
Article
Chemistry, Organic
Mikhail Kozlov, Alexey Tyurin, Andrey Dmitrenok, Vyacheslav Rusak, Aleksander Fedorov, Igor Zavarzin, Yulia Volkova
Summary: This study presents a novel and practical synthesis method for phosphorus-substituted 1,3,4-thiadiazolines using phosphorylthioformic acid hydrazides and ketones. The protocol demonstrates operational simplicity, availability of reagents, and tolerance towards different functional groups.
Article
Chemistry, Organic
Jisna Jose, Thomas Mathew
Summary: 2-Cyclopentenone and its derivatives are highly esteemed synthetic intermediates with exceptional utility in organic synthesis. They are favored structural motifs in numerous pharmaceutical drugs and natural products, highlighting their significance. The review discusses the various methods used to synthesize cyclopentenones from 2016 to 2023.