Article
Chemistry, Multidisciplinary
Shaotong Qiu, Xiang Gao, Shifa Zhu
Summary: A dirhodium-catalyzed asymmetric cycloisomerization reaction of azaenyne was successfully achieved through a cap-tether synergistic modulation strategy, leading to a variety of centrally chiral isoindazole derivatives. This strategy demonstrated high synthetic utility, with high yields and enantioselectivity achievable in the products.
Review
Chemistry, Organic
Anthony Abshire, Desiree Moore, Jobe Courtney, Ampofo Darko
Summary: This review highlights the applications of dirhodium(ii,ii) paddlewheel complexes with a heteroleptic scaffold. It emphasizes the benefits of using heteroleptic complexes as carbene transfer catalysts and encourages future research in this area. The review also discusses methods to synthesize heteroleptic dirhodium(ii,ii) paddlewheel complexes and categorizes their types and carbene reactions.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2021)
Review
Chemistry, Inorganic & Nuclear
Radim Hrdina
Summary: Homoleptic dirhodium(II,II) paddlewheel complexes with the general formula Rh(2)A(4) have diverse applications in chemical research and industry, serving as catalysts, detectors, enzymatic inhibitors, or building blocks for molecular scaffolds. They are commonly used in organic synthesis to transfer electron-deficient species, activate unsaturated bonds, catalyze hydrogenation, and participate in oxidation/reduction processes. The complexes can be prepared from basic inorganic precursors or post-functionalization of paddlewheel structures, allowing modulation of electrochemical potential, geometry, and physical/chemical properties of the metal complex.
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Lei Shi, Xiaoping Xue, Biqiong Hong, Qigang Li, Zhenhua Gu
Summary: A dirhodium(II)/phosphine catalyst was developed for the asymmetric arylation of phenanthrene-9,10-diones with arylboronic acids. The chiral environment at the bridging site and tuning of axial and bridging ligands enabled highly enantioselective carbonyl addition reaction. Kinetic analysis showed that the rate-determining step involved the dirhodium(II) complex and arylboronic acid. Axially chiral biaryls were prepared through an oxidative ring-opening reaction.
ACS CENTRAL SCIENCE
(2023)
Article
Chemistry, Multidisciplinary
Andrea Cataffo, Miguel Pena-Lopez, Riccardo Pedrazzani, Antonio M. Echavarren
Summary: This study presents two classes of stereoselective cyclizations using a chiral auxiliary approach. The first class involves the stereoselective cascade cyclization of 1,5-enynes using Oppolzer camphorsultam as chiral auxiliary, leading to the synthesis of enantioenriched spirocyclic ketones. The second class focuses on the stereoselective alkoxycyclization of 1,6-enynes mediated by Evans-type oxazolidinone, resulting in the formation of enantioenriched beta-tetralones after removal of the auxiliary.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Adam I. Green, Christopher P. Tinworth, Stuart Warriner, Adam Nelson, Natalie Fey
Summary: Dirhodium(II) catalysts have diverse properties, and a database based on DFT-calculated parameters has been developed to aid in catalyst selection and exploration of reactivity.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Physical
Stephen de Doncker, Gregory S. Smith, Siyabonga Ngubane
Summary: This article describes the synthesis of a series of cationic bimetallic complexes and their catalytic performance in the hydroformylation reaction. By adjusting the substituents and counter ions, successful recycling of the catalyst precursors was achieved.
APPLIED CATALYSIS A-GENERAL
(2023)
Review
Chemistry, Organic
Samata E. Shetgaonkar, Fateh V. Singh
Summary: Hypervalent iodine catalysis is a fast-growing field in hypervalent iodine chemistry. Recent research has focused on the discovery of new chiral hypervalent iodine catalysts and their application in stereoselective reactions. These catalysts have been successful in achieving high enantiomeric excess in various organic transformations.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Jie Huang, Jiaonan Sun, Yiying Wu, Claudia Turro
Summary: A new Rh-2(II,II) dimer has been synthesized and anchored onto a NiO photocathode, acting as both sensitizer and catalyst for hydrogen production. This single-molecule design simplifies the hydrogen production pathway and allows for greater absorption of solar irradiance compared to traditional dyes, offering a promising new system for solar fuel production.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Organic
Liang-Liang Yang, Jin Cao, Tian-Yuan Zhao, Shou-Fei Zhu, Qi-Lin Zhou
Summary: The highly enantioselective Si-H bond insertion reaction of alpha-aryldiazoacetates catalyzed by chiral spiro dirhodium tetraphosphate was successfully developed, leading to the preparation of various chiral alpha-silyl esters with high yield and excellent enantioselectivity. Even challenging substrates for other chiral dirhodium catalysts showed good results in this reaction, making it one of the few successful applications of chiral dirhodium phosphates in asymmetric catalysis.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Zhiying Fan, Zhifan Wang, Ruoyi Shi, Yuanhua Wang
Summary: Unlike the conventional C-N bond formation with dirhodium(ii)-nitrenoids, dirhodium(ii)-catalyzed 1,2- and 1,3-diamination reactions proceed through a free radical mechanism. A mechanistic study revealed a radical-polar crossover process during the reactions. UV-visible spectroscopy enables accurate observation of catalyst valence state changes and rapid determination of reaction end time based on solution color changes.
ORGANIC CHEMISTRY FRONTIERS
(2021)
Article
Chemistry, Inorganic & Nuclear
Dennis S. Pietruschka, Bharti Kumari, Gerd Buntkowsky, Torsten Gutmann, Doreen Mollenhauer
Summary: Dirhodium(II) complexes bound to a functionalized mesoporous SBA-15 carrier have been studied for heterogeneous catalysis in pharmaceutical synthesis. The mechanistic steps of immobilization through linker molecules with carboxyl or amine functionalities are still under discussion. Theoretical studies suggest initial binding through a carboxyl-functionalized linker as the most favorable reaction pathway for the formation of immobilization products.
INORGANIC CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Xiao-Bing Chen, Damian Padin, Charlotte. N. N. Stindt, Ben. L. L. Feringa
Summary: In this paper, a novel strategy for the stereocontrolled synthesis of versatile chiral P-stereogenic alkenylphosphonamidates is reported. This strategy involves a one-pot Ni-catalyzed C-P coupling/diastereoselective hydrolysis of readily available phosphoramidites and alkenyl halides. The reaction conditions were found to exhibit chemo- and diastereodivergent behavior, and the chiral alkenylphosphonamidates obtained can be selectively derivatized for the synthesis of structurally diverse P-stereogenic compounds.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Michal Kriegelstein, David Profous, Adam Pribylka, Antonin Lycka, Petr Cankar
Summary: This study used TBBA as a chiral derivatizing agent to evaluate the limits of absolute configuration assignment for beta-chiral aminoalcohols. The results showed that hydrogen bond formation and steric hindrance were the main factors affecting the correct assignment for Boc-aminoalcohols.
Article
Materials Science, Paper & Wood
Lorenz Roesler, Mark Hoefler, Hergen Breitzke, Till Wissel, Kevin Herr, Henrike Heise, Torsten Gutmann, Gerd Buntkowsky
Summary: A novel and efficient approach was developed for the functionalization of microcrystalline cellulose (MCC) in order to immobilize chiral dirhodium catalysts for asymmetric cyclopropanation reactions. The modified cellulose material showed excellent stability and good separation characteristics. The produced catalyst demonstrated high enantioselectivity and recyclability in the cyclopropanation reaction.
Article
Biochemical Research Methods
Priscila Aburachid Cardoso, Diego Beltrao Pereira, Mohammed Farrag El-Behairy, Ashraf Ghanem, Gerson Antonio Pianetti, Isabela Costa Cesar
JOURNAL OF CHROMATOGRAPHIC SCIENCE
(2019)
Article
Biochemistry & Molecular Biology
Ali Fouad, Montaser Sh. A. Shaykoon, Samy M. Ibrahim, Sobhy M. El-Adl, Ashraf Ghanem
Review
Chemistry, Analytical
Ali Fouad, Diana Ibrahim, Frady G. Adly, Ashraf Ghanem
JOURNAL OF SEPARATION SCIENCE
(2019)
Article
Biochemistry & Molecular Biology
Diana Ibrahim, Ashraf Ghanem
Editorial Material
Chemistry, Physical
Frady G. Adly, Ashraf Ghanem
Article
Chemistry, Multidisciplinary
Zhen Jiang, Ming Li Tan, Mahdiar Taheri, Qiao Yan, Takuya Tsuzuki, Michael G. Gardiner, Broden Diggle, Luke A. Connal
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2020)
Article
Chemistry, Multidisciplinary
Stephanie A. Boer, Li-Juan Yu, Tobias L. Genet, Kaycee Low, Duncan A. Cullen, Michael G. Gardiner, Michelle L. Coote, Nicholas G. White
Summary: Despite the similar appearance of framework materials based on tetraphenylmethane and tetraphenylsilane building blocks, their structures and topologies can often be quite different, depending on the type of anions used. This difference may be attributed to the varying geometrical flexibility between silicon and carbon tetraamidinium compounds.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Biochemistry & Molecular Biology
Ali Fouad, Adel A. Marzouk, Montaser Sh. A. Shaykoon, Samy M. Ibrahim, Sobhy M. El-Adl, Ashraf Ghanem
Summary: Daptomycin, a macrocyclic antibiotic, was used as a new chiral selector in the preparation of a chiral stationary phase in a polymer monolithic capillary. The capillaries prepared showed baseline separation for many racemic drugs under reversed-phase HPLC, expanding the horizons of chiral selectors in HPLC.
Article
Chemistry, Inorganic & Nuclear
Catriona R. Vanston, Thomas P. Nicholls, Alex C. Bissember, Michael G. Gardiner, Curtis C. Ho
Summary: This study prepared palladium complexes with a new class of cationic aNHC ligands, but found that greater conformational restrictions are necessary to achieve significant electron transfer.
INORGANIC CHEMISTRY
(2022)
Article
Biochemical Research Methods
Ashraf Ghanem, Adel A. Marzouk, Sobhy M. El-Adl, Ali Fouad
Summary: This study reports the first use of Polymyxin-B antibiotic as an enantio-selector in polymer monolithic capillary for the enantioselective nanoHPLC separation of 50 racemic pharmaceutical drugs. Polymyxin-B was immobilized or encapsulated within the organic polymer, leading to acceptable resolution of 21 drugs under RP-HPLC conditions. This development represents a promising expansion of platform in enantioselective HPLC separations.
JOURNAL OF CHROMATOGRAPHY A
(2022)
Article
Chemistry, Multidisciplinary
Li Feng Lim, Martyna Judd, Petra Vasko, Michael G. Gardiner, Dimitrios A. Pantazis, Nicholas Cox, Jamie Hicks
Summary: An isostructural series of heavy Group 14 E(I) radical anions (Ge, Sn, Pb), stabilized by a bulky xanthene-based diamido ligand, were synthesized and characterized. The E(II) precursor complexes were one-electron reduced with sodium naphthalenide in THF, yielding the charge-separated radical anions as sodium salts. The comprehensive characterization using EPR spectroscopy, X-ray crystallography, and DFT analysis revealed that the spin density of the unpaired electron is mainly located in a p-orbital of pi symmetry on the Group 14 center in all cases.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Yi-Min Fan, Li-Juan Yu, Michael G. Gardiner, Michelle L. Coote, Michael S. Sherburn
Summary: The diene-transmissive hetero-Diels-Alder sequences involving carbonyl dienophiles are reported for the first time. High enantioselectivities are achieved through the optimization of a Pd2+ catalyst system. The reaction generates fused polycyclic systems containing both heterocycles and carbocycles.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Biochemistry & Molecular Biology
Ali Fouad, Frady G. Adly, Moustafa K. Soltan, Ashraf Ghanem
Summary: In this study, lipase was immobilized on single-walled carbon nanotubes (SWCNTs) for use as an enantioselector in capillary monolithic columns for chiral separation of pharmaceuticals. The columns were prepared by encapsulating functionalized SWCNTs within an organic monolithic polymer and immobilizing lipase over the resulting monolith. The developed c-SWCNT-lipase-based polymeric monolithic capillaries showed promising potential for separating pharmaceutical enantiomers using nano-HPLC.
Article
Chemistry, Multidisciplinary
Quoc Hoang Pham, Andrew J. Tague, Christopher Richardson, Michael G. Gardiner, Stephen G. Pyne, Christopher J. T. Hyland
Summary: A Pd-catalysed (3 + 2) cycloaddition reaction of bis(trifluoroethyl) 2-vinyl-cyclopropane-1,1-dicarboxylate (VCP) with cyclic sulfamidate imine-derived 1-azadienes (SDAs) has been developed, leading to highly functionalized spiroheterocycles with three contiguous stereocentres, including a tetrasubstituted carbon bearing an oxygen functionality. The geminal trifluoroethyl ester groups can be selectively manipulated to afford spirocycles with four contiguous stereocentres. Additionally, reduction of the imine moiety can introduce a fourth stereocentre and expose a 1,2-amino alcohol functionality.
Article
Chemistry, Multidisciplinary
Matthew J. Evans, Michael G. Gardiner, Mathew D. Anker, Martyn P. Coles
Summary: The study found that (NONDipp)Al-K(TMEDA)(2) and dimeric potassium aluminyl [K{Al(NONDipp)}](2) can activate and reductively couple carbon monoxide gas to form aluminium complexes with unique ligands.
CHEMICAL COMMUNICATIONS
(2022)
Article
Chemistry, Organic
Faiza Diaba, Gisela Trenchs
Summary: The first violet light-mediated synthesis of gamma- and delta-lactams from N-alkenyl trichloroacetamides is reported in this paper. The reactions are conducted in tetrahydrofuran or 2-methyltetrahydrofuran as the sole solvent without catalysts or additives, under non-anhydrous conditions in an air atmosphere where the solvent serves as the radical initiator.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2024)
Article
Chemistry, Organic
Feroze Hussain, Sajjad Ahmed, Ashiq Hussain Padder, Qazi Naveed Ahmed
Summary: This study reports a novel and efficient one-pot synthesis method for mixed phosphorotrithioates, which does not require supplementary additives and shows broad applicability.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2024)
Article
Chemistry, Organic
Hyunjin Oh, Ikyon Kim
Summary: A new 1,2,4-triazole-pyrrolo[1,2-a]pyrazine hybrid system, 6-acylpyrrolo[1,2-a][1,2,4]triazolo[5,1-c]pyrazine, was synthesized using a catalyst-free method. This method involved sequential exposure of pyrrole-2-carbonitrile-derived substrates to DMF-DMA and acyl hydrazide, resulting in the formation of acylated pyrazine and 1,2,4-triazole rings, enabling the installation of various substituents at specific positions on the core skeleton.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2024)
Article
Chemistry, Organic
Ming Yan, Si-fan Wang, Yong-po Zhang, Jin-zhong Zhao, Zhuo Tang, Guang-xun Li
Summary: Here we developed an efficient photocatalytic approach for the convenient preparation of sulfinamides. The reaction allows for the gram-scale preparation of sulfinamides and the one-pot synthesis of various sulfonyl amides.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2024)
Article
Chemistry, Organic
Farzaneh Bandehali-Naeini, Zahra Tanbakouchian, Noushin Farajinia-Lehi, Nicolas Mayer, Morteza Shiri, Martin Breugst
Summary: Two tandem catalytic systems were developed for the synthesis of novel 3,4-disubstituted maleimides using the same Ugi adducts. Different maleimide structures can be synthesized using either Pd or Cu catalysis.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2024)
Article
Chemistry, Organic
Tanya Raghava, Anjan Chattopadhyay, Subhadeep Banerjee, Nivedita Sarkar
Summary: Amine substitution of two ortho fluorine atoms of tetrafluoroterephthalonitrile through SNAr chemistry is easily achievable. But further fluorine substitution is only possible under forcing conditions, yielding valuable fluorophores for bioimaging.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2024)
Review
Chemistry, Organic
Anju Chadha, Santosh Kumar Padhi, Selvaraj Stella, Sowmyalakshmi Venkataraman, Thangavelu Saravanan
Summary: Alcohol dehydrogenases are enzymes that use cofactors for oxidation or reduction reactions of alcohols or carbonyl compounds. They are utilized in green chemistry and have applications in the production of pharmaceuticals. Recombinant enzymes have solved the challenge of producing purified enzymes in large quantities. Engineered alcohol dehydrogenases have been used in asymmetric synthesis in industry. Various methods have been established for regenerating expensive cofactors to make the enzymatic process more efficient and economically viable.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2024)