Article
Chemistry, Organic
Jyotshna Phukon, Pratiksha Bhorali, Sumi Changmai, Sanjib Gogoi
Summary: An unprecedented annulation reaction is developed using easily affordable sulfoxonium ylides and 1,4-dioxane as the annulating partners for the synthesis of dihydrofuran-fused compounds. This is the first example of using 1,4-dioxane as a methylene source to construct a heterocyclic scaffold. A wide range of dihydrofuran-fused coumarins and naphthalenes were synthesized using this three-component reaction.
Article
Chemistry, Organic
Nayana Nayek, Goutam Brahmachari
Summary: A photochemical method using visible light (white LEDs/sunlight) has been developed for efficient and selective C(sp(2))-H selenylation and sulfenylation of substituted 2-amino-1,4-naphthoquinones. This metal-free protocol offers the advantages of no external photoredox catalysts, use of visible light/sunlight as energy sources, good substrate scope, and moderate to good yields (41-91%) with high regioselectivity.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Jin Cao, Meng-Yang Hu, Si-Yuan Liu, Xin-Yu Zhang, Shou-Fei Zhu, Qi-Lin Zhou
Summary: This study presents highly enantioselective silicon-directed Nazarov reactions cooperatively catalyzed by a Lewis acid and a chiral Bronsted acid, which allows for the synthesis of chiral cyclopentenones with diverse substituent patterns not achievable by other catalytic enantioselective reactions. The positioning of the double bond in the product is determined by the stabilizing effect of the silicon group in the dienone substrate on the beta-carbocation intermediate, and the enantioselectivity of the reaction is attributed to a chiral Bronsted acid promoted proton transfer reaction of the enol intermediate.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Multidisciplinary
Sailu Munnuri, John R. Falck
Summary: In this study, Iminodirhodium reactive intermediates were generated from O-tosyloximes and utilized for three challenging transformations, including remote C-H functionalization, desaturative annulation, and directed desaturation. These reactions, which have been underexplored in previous studies, were successfully achieved under mild conditions.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Organic
Fang Yang, Qiuju Zhou, Heyan Wang, Lin Tang
Summary: The study utilizes Cu(OAc)2∙H2O and K2S2O8 to activate H-phosphonates to generate dialkyl phosphoryl radicals, enabling accurate preparation of various phosphoryl-functionalized 2-amino-1,4-naphthoquinones. This method features a broad substrate scope and practical application for C-P bond formation.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Peng-Fei Cui, Xin-Ran Liu, Shu-Ting Guo, Yue-Jian Lin, Guo-Xin Jin
Summary: This study demonstrates how steric effects can be used to achieve regioselective B-H activation in para-carboranes, with different activation patterns achieved by utilizing pi-pi interactions between pyridine ligands and host-guest interactions in metallacage compounds.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Organic
Xiaosa Lu, Yinhua Huang
Summary: A new method for the stereospecific cyanation of olefinic C-H bonds using rhodium catalysis has been developed, resulting in the synthesis of beta,beta-disubstituted acrylonitriles under mild conditions. This approach does not require directing groups, tolerates various functional groups, and provides a concise and green access to a wide range of disubstituted acrylonitriles in good to excellent yields.
ORGANIC CHEMISTRY FRONTIERS
(2021)
Article
Chemistry, Multidisciplinary
Anna Skrzynska, Sebastian Frankowski, Aleksandra Topolska, Mateusz Dyguda, Xin-Yue Gao, Chang-Jiang Xu, Ying-Chun Chen, Lukasz Albrecht
Summary: In this work, a novel H-bond-directed vinylogous iminium ion strategy has been developed for the gamma, delta-functionalization of vinyl-substituted heteroaromatic aldehydes. The strategy allows for the synthesis of tricyclic compounds with excellent stereoselectivity, demonstrating the potential applications in complex molecule synthesis.
CHEMICAL COMMUNICATIONS
(2021)
Article
Chemistry, Organic
Kaijie Wei, Siyu Liang, Tonghao Yang, Wei Yu
Summary: In this study, a novel iron-catalyzed skeleton rearrangement of alkyl azides was reported. The reaction proceeds through a series of steps to generate the desired product in good yield.
Article
Chemistry, Organic
Nao Shimizu, Hajime Shigemitsu, Toshiyuki Kida, Thorsten Bach, Tadashi Mori
Summary: A range of asymmetric photochemical transformations using visible light have recently become considerably attractive. Chiral Lewis acid association to enones for [2 + 2] and ortho photocycloadditions and oxadi-pi-methane rearrangements have shown to be very promising in achieving effective enantiodifferentiation. In this study, we investigated the regio- and enantiodifferentiation of [2 + 2] photocycloaddition reactions of naphthoquinone derivatives mediated by chiral oxazaborolidines. We found that the excited-state decomplexation is a key factor in achieving high regio- and enantioselectivities in the photocycloaddition reactions.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Michael W. Milbauer, Jeff W. Kampf, Melanie S. Sanford
Summary: In this study, we successfully isolated a cyclometalated nickel(IV) complex that is similar to a key intermediate proposed in aminoquinoline-directed C-H functionalization catalysis. The complex undergoes bond-forming reaction under mild conditions and demonstrates the importance of LX-type ligands in stabilizing these nickel(IV) species.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Multidisciplinary Sciences
Suman K. Barman, Meng-Yin Yang, Trenton H. Parsell, Michael T. Green, A. S. Borovik
Summary: This study explores the mechanism of metal-oxido species in C-H bond cleavage, highlighting the importance of basicity in achieving enzymatic function. The research found that proton transfer plays a more dominant role than electron transfer in these reactions.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Review
Chemistry, Organic
Aniruddha Paik, Sabarni Paul, Sabyasachi Bhowmik, Rahul Das, Togati Naveen, Sujoy Rana
Summary: This review discusses the importance of organic halides as crucial organic compounds and the significance of high regioselectivity in synthetic chemistry. Selective halogenation reactions are achieved through metalloenzymes and biomimetic approaches, as well as impressive development in transition metal-catalyzed halogenation reactions.
ASIAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Takeru Miyakoshi, Nadja E. Niggli, Olivier Baudoin
Summary: In the past years, Pd-0-catalyzed C(sp(3))-H activation has provided efficient and economical methods for synthesizing carbo- and heterocycles via direct C(sp(2))-C(sp(3)) bond formation. This study reports a 1,4-Pd shift that enables the synthesis of N-heterocycles, which are difficult to build through direct reactions. The reaction involves the 1,4-Pd shift of o-bromo-N-methylanilines at the N-methyl group, followed by intramolecular trapping and remote C-C bond formation, resulting in the formation of biologically relevant isoindolines and beta-lactams. The selectivity of the reaction is influenced by the choice of ligand, with NHCs favoring the formation of products through remote C-C coupling.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Organic
Yi-Tan Su, Zheng-Chun Yin, Guan-Wu Wang
Summary: In this study, a palladium-catalyzed three-component alkoxyarylation reaction was conducted to synthesize a series of 1,4-(alkoxy)(aryl)[60]fullerene derivatives. Plausible reaction pathways for the formation of 1,4-(alkoxy)(aryl)[60]fullerenes were proposed. The electrochemical properties of the synthesized adducts were also investigated.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Biochemistry & Molecular Biology
Krzysztof Kaczmarek, Barbara Pacholczyk-Sienicka, Lukasz Albrecht, Janusz Zabrocki, Ronald J. Nachman
Summary: A facile solid-phase synthetic method for incorporating the imidazoline ring motif into bioactive peptides is reported. An imidazoline peptidomimetic analog of an insect pyrokinin neuropeptide was synthesized via a cyclization reaction of an iminium salt generated from the preceding amino acid and 2,4-diaminopropanoic acid (Dap).
Article
Biochemistry & Molecular Biology
Maciej Saktura, Anna Skrzynska, Sebastian Frankowski, Sylwia Wodka, Lukasz Albrecht
Summary: An organocatalytic 1,3-dipolar cycloaddition reaction between 2-nitrobenzofurans or 2-nitrobenzothiophene and N-2,2,2-trifluoroethyl-substituted isatin imines has been developed in this study. The stereochemical efficiency of the process was crucially dependent on the use of squaramide derivative in bifunctional organocatalysis. The utility of the obtained cycloadducts was confirmed in selected transformations, including the removal of nitro groups via both aromative and non-aromative pathways.
Article
Chemistry, Applied
Artur Przydacz, Aleksandra Topolska, Anna Skrzynska, Sebastian Frankowski, Lukasz Albrecht
Summary: This manuscript presents the application of amino isobenzofulvene intermediates as pentaenamines in a 1,6-addition reaction. The alkylation of the indene ring in indene-2-carbaldehydes with para-quinone methides was achieved, with the stereoselectivity controlled by C-2-symmetric 2,5-diphenylpyrrolidine. The developed process utilizes the reactivity of amino isobenzofulvene intermediates derived from indene-2-carbaldehydes in a non-cycloadditive manner.
ADVANCED SYNTHESIS & CATALYSIS
(2022)
Article
Chemistry, Applied
Artur Przydacz, Aleksandra Topolska, Anna Skrzynska, Lukasz Albrecht
Summary: A dearomative formal (4+2)-cycloaddition reaction has been established using NHC-catalysis between 2-substituted 3-furaldehydes derivatives and isatins or alpha,alpha,alpha-trifluoroacetophenones. Highly reactive NHC-bound heterocyclic o-QDM intermediates derived from 3-furaldehydes play a key role in the process, leading to the formation of structurally diverse 6,7-dihydro-4H-furo[3,2-c]pyran-4-ones in moderate to high yields. The obtained (4+2)-cycloadducts also show potential in the synthesis of spirooxindole derivatives containing 6,7-dihydro-4H-furo[3,2-c]pyran scaffold.
ADVANCED SYNTHESIS & CATALYSIS
(2022)
Article
Chemistry, Organic
Aleksandra Topolska, Sebastian Frankowski, Lukasz Albrecht
Summary: The application of differentiating catalysis in the [4 + 2]-cycloaddition reaction between 2-alkyl-3-formylheteroarenes and alpha,beta-unsaturated aldehydes is described in this paper. The use of the same aminocatalyst allows for independent activation of both starting materials, achieving high enantio- and diastereoselectivity through LUMO-lowering and HOMO-rising principles. The combination of dearomative dienamine activation with iminium ion chemistry further improves the outcome of the process.
Article
Chemistry, Organic
Marta Romaniszyn, Leslaw Sieron, Lukasz Albrecht
Summary: This study demonstrates the use of organocatalytic Brønsted base activation to generate 2π-components for the diastereoselective [8 + 2]-cycloaddition reaction involving 8,8-dicyanoheptafulvene. The use of dienolates leads to the formation of biologically relevant polycyclic products bearing a γ-butyrolactone structural motif, thus expanding the synthetic potential of Brønsted base activated higher-order cycloadditions.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Marek Moczulski, Angelika Artelska, Lukasz Albrecht, Anna Albrecht
Summary: The photocatalytic decarboxylative alkylation of 3-cyanochromones using triphenylphosphine and potassium iodide as photoredox-mediators has been described. This method is cost-effective and interesting, and allows for obtaining a number of biologically relevant products.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Biochemistry & Molecular Biology
Barbara Pacholczyk-Sienicka, Grzegorz Ciepielowski, Jakub Modranka, Tomasz Bartosik, Lukasz Albrecht
Summary: The targeted quantitative NMR (qNMR) approach is a powerful tool for classifying and determining the authenticity of honey samples. In this study, the chemical profiles of different types of Polish honey samples were determined using qNMR, and pattern recognition was performed using principal component analysis (PCA). The results showed that qNMR combined with chemometric analysis can be used as a supplementary tool for specifying honeys.
Article
Chemistry, Applied
Justyna Kowalska, Beata Lukasik, Sebastian Frankowski, Leslaw Sieron, Lukasz Albrecht
Summary: This paper demonstrates the application of organocatalysis in the synthesis of 2,3-dihydro-1H-pyrrolizines. The formal (3+2)-cycloaddition of alpha,beta-unsaturated aldehydes and pyrrole-based hydrazone was achieved through aminocatalytic iminium ion activation, resulting in products with high chemical yields and excellent stereocontrol. The developed method was also utilized in the first organocatalytic synthesis of the non-steroidal anti-inflammatory drug ketorolac.
ADVANCED SYNTHESIS & CATALYSIS
(2022)
Letter
Chemistry, Organic
Marta Romaniszyn, Anna Skrzynska, Joanna Dybowska, Lukasz Albrecht
Summary: A novel organocatalytic reaction cascade has been described for the stereocontrolled functionalization of cyanocoumarins, producing biologically active coumarin and delta-lactone-fused products.
Article
Chemistry, Medicinal
Eduardo Felipe Alves Fernandes, Jonas Wilbs, Rene Raave, Christian Borch Jacobsen, Hanne Toftelund, Hans Helleberg, Milou Boswinkel, Sandra Heskamp, Magnus Bernt Frederik Gustafsson, Inga Bjornsdottir
Summary: Positron emission tomography (PET) is a non-invasive molecular imaging technique used to visualize the distribution and pharmacology of tracers. This study compared the biodistribution profiles obtained using Zirconium-89 (Zr-89) PET and quantitative whole-body auto-radiography (QWBA) and found consistent profiles during the absorption phase but differences during the elimination phase.
ACS PHARMACOLOGY & TRANSLATIONAL SCIENCE
(2022)
Article
Chemistry, Multidisciplinary
Mateusz Dyguda, Anna Skrzynska, Leslaw Sieron, Lukasz Albrecht
Summary: This manuscript describes the first enantioselective dearomative Michael addition between alpha,beta-unsaturated aldehydes and 2-nitrobenzofurans realized under N-heterocyclic carbene activation. The reaction can efficiently form biologically important heterocycles with high yields and stereoselectivities.
CHEMICAL COMMUNICATIONS
(2022)
Article
Chemistry, Multidisciplinary
Marek Moczulski, Ewelina Kowalska, Elzbieta Kusmierek, Lukasz Albrecht, Anna Albrecht
Summary: This study describes a doubly decarboxylative, photoredox synthesis method which successfully synthesized 4-substituted-chroman-2-ones and 2-substituted-chroman-4-ones. Key parameters include visible light, photoredox catalyst, base, anhydrous solvent, and inert atmosphere.
Article
Biochemistry & Molecular Biology
Barbara Pacholczyk-Sienicka, Grzegorz Ciepielowski, Lukasz Albrecht
Summary: Counterfeit goods are a major underground business globally, causing both financial losses to honest producers and potential health hazards to consumers. The perfume industry, especially in the realm of designer-inspired fragrances, is particularly susceptible to counterfeits, prompting the need for innovative authentication methods like H-1 NMR spectroscopy.
Article
Chemistry, Multidisciplinary
Beata Lukasik, Justyna Kowalska, Sebastian Frankowski, Lukasz Albrecht
Summary: A new umpolung approach has been developed for the asymmetric Friedel-Crafts-type alkylation of electron-poor heteroaromatic systems using hydrazones. The method shows excellent enantioselectivities under aminocatalytic conditions, and also provides a unique strategy for the asymmetric functionalization of electron-poor heteroaromatic systems.
CHEMICAL COMMUNICATIONS
(2021)
