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Díaz-Ruiz M, Nieto-Rodríguez M, Maseras F. Revealing the Mechanistic Features of an Electrosynthetic Catalytic Reaction and the Role of Redox Mediators through DFT Calculations and Microkinetic Modeling. Chemphyschem 2024; 25:e202400402. [PMID: 38739104 DOI: 10.1002/cphc.202400402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2024] [Revised: 05/09/2024] [Accepted: 05/10/2024] [Indexed: 05/14/2024]
Abstract
Organic electrosynthesis is an emerging field that provides original selectivity while adding features of atom economy, sustainability, and selectivity. Electrosynthesis is often enhanced by redox mediators or electroauxiliaries. The mechanistic understanding of organic electrosynthesis is however often limited by the low lifetime of intermediates and its difficult detection. In this work, we report a computational analysis of the mechanism of an appealing reaction previously reported by Mei and co-workers which is catalyzed by copper and employs iodide as redox mediator. Our scheme combines DFT calculations with microkinetic modeling and covers both the reaction in solution and the electrodic steps. A detailed mechanistic scheme is obtained which reproduces well experimental data and opens perspectives for the general treatment of these processes.
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Affiliation(s)
- Marina Díaz-Ruiz
- Institute of Chemical Research of Catalonia (ICIQ-CERCA), The Barcelona Institute of Science and Technology, Avgda. Països, Catalans 16, 43007, Tarragona, Spain
- Departament de Química Física i Inorgànica, Universitat Rovira i Virgili, Marcel⋅lí Domingo s/n, Tarragona, 43007, Spain
| | - Marc Nieto-Rodríguez
- Institute of Chemical Research of Catalonia (ICIQ-CERCA), The Barcelona Institute of Science and Technology, Avgda. Països, Catalans 16, 43007, Tarragona, Spain
- Departament de Química Física i Inorgànica, Universitat Rovira i Virgili, Marcel⋅lí Domingo s/n, Tarragona, 43007, Spain
| | - Feliu Maseras
- Institute of Chemical Research of Catalonia (ICIQ-CERCA), The Barcelona Institute of Science and Technology, Avgda. Països, Catalans 16, 43007, Tarragona, Spain
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2
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Hu X, Zhu Z, Li Z, Adili A, Odagi M, Abboud KA, Seidel D. Catalytic Enantioselective [4+2] Cycloadditions of Salicylaldehyde Acetals with Enol Ethers. Angew Chem Int Ed Engl 2024; 63:e202315759. [PMID: 38055210 DOI: 10.1002/anie.202315759] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 11/28/2023] [Accepted: 11/30/2023] [Indexed: 12/07/2023]
Abstract
A readily accessible conjugate-base-stabilized carboxylic acid (CBSCA) catalyst facilitates highly enantioselective [4+2] cycloaddition reactions of salicylaldehyde-derived acetals and cyclic enol ethers, resulting in the formation of polycyclic chromanes with oxygenation in the 2- and 4-positions. Stereochemically more complex products can be obtained from racemic enol ethers. Spirocyclic products are also accessible.
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Affiliation(s)
- Xiaojun Hu
- Center for Heterocyclic Compounds, Department of Chemistry, University of Florida, Gainesville, FL 32611, USA
| | - Zhengbo Zhu
- Center for Heterocyclic Compounds, Department of Chemistry, University of Florida, Gainesville, FL 32611, USA
| | - Zhongzheng Li
- Center for Heterocyclic Compounds, Department of Chemistry, University of Florida, Gainesville, FL 32611, USA
| | - Alafate Adili
- Center for Heterocyclic Compounds, Department of Chemistry, University of Florida, Gainesville, FL 32611, USA
| | - Minami Odagi
- Center for Heterocyclic Compounds, Department of Chemistry, University of Florida, Gainesville, FL 32611, USA
- Department of Biotechnology and Life Science, Graduate School of Technology, Tokyo University of Agriculture and Technology, 2-24-16, Naka-cho, Koganei city, 184-8588, Tokyo, Japan
| | - Khalil A Abboud
- Center for X-ray Crystallography, Department of Chemistry, University of Florida, Gainesville, FL 32611, USA
| | - Daniel Seidel
- Center for Heterocyclic Compounds, Department of Chemistry, University of Florida, Gainesville, FL 32611, USA
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3
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Cai Y, Lv Y, Shu L, Jin Z, Chi YR, Li T. Access to Axially Chiral Aryl Aldehydes via Carbene-Catalyzed Nitrile Formation and Desymmetrization Reaction. RESEARCH (WASHINGTON, D.C.) 2024; 7:0293. [PMID: 38628355 PMCID: PMC11020146 DOI: 10.34133/research.0293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Accepted: 12/08/2023] [Indexed: 04/19/2024]
Abstract
An approach utilizing N-heterocyclic carbene for nitrile formation and desymmetrization reaction is developed. The process involves kinetic resolution, with the axially chiral aryl monoaldehydes obtained in moderate yields with excellent optical purities. These axially chiral aryl monoaldehydes can be conveniently transformed into functionalized molecules, showing great potential as catalysts in organic chemistry.
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Affiliation(s)
- Yuanlin Cai
- National Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education,
Guizhou University, Guiyang 550025, China
| | - Ya Lv
- National Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education,
Guizhou University, Guiyang 550025, China
| | - Liangzhen Shu
- National Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education,
Guizhou University, Guiyang 550025, China
| | - Zhichao Jin
- National Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education,
Guizhou University, Guiyang 550025, China
| | - Yonggui Robin Chi
- National Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education,
Guizhou University, Guiyang 550025, China
- School of Chemistry, Chemical Engineering, and Biotechnology,
Nanyang Technological University, Singapore 637371, Singapore
| | - Tingting Li
- National Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education,
Guizhou University, Guiyang 550025, China
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4
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Sun C, Li T. Chiral Carboxylic Acids as Organic Catalysts for Asymmetric Reactions. ChemistrySelect 2023. [DOI: 10.1002/slct.202300010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/05/2023]
Affiliation(s)
- Cuiyun Sun
- National Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education Guizhou University Guiyang 550025 China
| | - Tingting Li
- National Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education Guizhou University Guiyang 550025 China
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5
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Dunning SG, Chen B, Zhu L, Cody GD, Chariton S, Prakapenka VB, Zhang D, Strobel TA. Synthesis and Post-Processing of Chemically Homogeneous Nanothreads from 2,5-Furandicarboxylic Acid. Angew Chem Int Ed Engl 2023; 62:e202217023. [PMID: 36757113 DOI: 10.1002/anie.202217023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 01/09/2023] [Accepted: 02/06/2023] [Indexed: 02/10/2023]
Abstract
Compared with conventional, solution-phase approaches, solid-state reaction methods can provide unique access to novel synthetic targets. Nanothreads-one-dimensional diamondoid polymers formed through the compression of small molecules-represent a new class of materials produced via solid-state reactions, however, the formation of chemically homogeneous products with targeted functionalization represents a persistent challenge. Through careful consideration of molecular precursor stacking geometry and functionalization, we report here the scalable synthesis of chemically homogeneous, functionalized nanothreads through the solid-state polymerization of 2,5-furandicarboxylic acid. The resulting product possesses high-density, pendant carboxyl functionalization along both sides of the backbone, enabling new opportunities for the post-synthetic processing and chemical modification of nanothread materials applicable to a broad range of potential applications.
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Affiliation(s)
- Samuel G Dunning
- Earth and Planets Laboratory, Carnegie Institution for Science, Washington, DC-20015, USA
| | - Bo Chen
- Donostia International Physics Center, Paseo Manuel de Lardizabal, 4, 20018, Donostia-San Sebastian, Spain.,IKERBASQUE, Basque Foundation for Science, Plaza Euskadi 5, 48009, Bilbao, Spain
| | - Li Zhu
- Physics Department, Rutgers University-Newark, 101 Warren Street, Newark, NJ-07102, USA
| | - George D Cody
- Earth and Planets Laboratory, Carnegie Institution for Science, Washington, DC-20015, USA
| | - Stella Chariton
- Center for Advanced Radiation Sources, The University of Chicago, Chicago, IL-60637, USA
| | - Vitali B Prakapenka
- Center for Advanced Radiation Sources, The University of Chicago, Chicago, IL-60637, USA
| | - Dongzhou Zhang
- Hawaii Institute of Geophysics and Planetology, School of Ocean and Earth Science and Technology, University of Hawaii at Manoa, Honolulu, HI-96822, USA
| | - Timothy A Strobel
- Earth and Planets Laboratory, Carnegie Institution for Science, Washington, DC-20015, USA
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6
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Vallaro M, Ermondi G, Saame J, Leito I, Caron G. Ionization and lipophilicity in nonpolar media mimicking the cell membrane interior. Bioorg Med Chem 2023; 81:117203. [PMID: 36796127 DOI: 10.1016/j.bmc.2023.117203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 01/25/2023] [Accepted: 02/03/2023] [Indexed: 02/09/2023]
Abstract
Ionization and lipophilicity may vary with the environment. Therefore, in this study we provide some insight in the performances of different experimental techniques (potentiometry, UV-vis, shake-flask and chromatography) to determine ionization and lipophilicity in more nonpolar systems than those commonly used in drug discovery. To this purpose a pool of 11 compounds of pharmaceutical interest was firstly submitted to a few experimental techniques to measure pKa in water, water/acetonitrile mixtures and pure acetonitrile. Then we measured logP/logD with shake-flask and potentiometry in octanol/water and toluene/water and also determined a chromatographic lipophilicity index (log k'80 PLRP-S) in a nonpolar system. Results show that ionization decreases for both acids and bases in a coherent, significant but not dramatical extent when water is present in the system, but the picture is completely different in pure acetonitrile. Lipophilicity may vary or not with the environment according to the chemical structure of the investigated compounds as also revealed by electrostatic potential maps. Since the internal core of cell membranes is largely nonpolar, our results support the need of extending the pool of physicochemical descriptors to be determined in the various stages of drug discovery programs and indicate some experimental strategies for their determination.
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Affiliation(s)
- Maura Vallaro
- Molecular Biotechnology and Health Sciences Dept., Università degli Studi di Torino, via Quarello 15, 10135 Torino, Italy
| | - Giuseppe Ermondi
- Molecular Biotechnology and Health Sciences Dept., Università degli Studi di Torino, via Quarello 15, 10135 Torino, Italy
| | - Jaan Saame
- University of Tartu, Institute of Chemistry, Ravila 14a, Tartu 50411, Estonia
| | - Ivo Leito
- University of Tartu, Institute of Chemistry, Ravila 14a, Tartu 50411, Estonia
| | - Giulia Caron
- Molecular Biotechnology and Health Sciences Dept., Università degli Studi di Torino, via Quarello 15, 10135 Torino, Italy.
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7
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Adili A, Webster JP, Zhao C, Mallojjala SC, Romero-Reyes MA, Ghiviriga I, Abboud KA, Vetticatt MJ, Seidel D. Mechanism of a Dually Catalyzed Enantioselective Oxa-Pictet-Spengler Reaction and the Development of a Stereodivergent Variant. ACS Catal 2023; 13:2240-2249. [PMID: 37711191 PMCID: PMC10501388 DOI: 10.1021/acscatal.2c05484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Enantioselective oxa-Pictet-Spengler reactions of tryptophol with aldehydes proceed under weakly acidic conditions utilizing a combination of two catalysts, an indoline HCl salt and a bisthiourea compound. Mechanistic investigations revealed the roles of both catalysts and confirmed the involvement of oxocarbenium ion intermediates, ruling out alternative scenarios. A stereochemical model was derived from density functional theory calculations, which provided the basis for the development of a highly enantioselective stereodivergent variant with racemic tryptophol derivatives.
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Affiliation(s)
- Alafate Adili
- Center for Heterocyclic Compounds, Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
| | - John-Paul Webster
- Department of Chemistry, Binghamton University, Binghamton, New York 13902, United States
| | - Chenfei Zhao
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, United States
| | | | - Moises A Romero-Reyes
- Center for Heterocyclic Compounds, Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
| | - Ion Ghiviriga
- Center for NMR Spectroscopy, Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
| | - Khalil A Abboud
- Center for X-ray Crystallography, Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
| | - Mathew J Vetticatt
- Department of Chemistry, Binghamton University, Binghamton, New York 13902, United States
| | - Daniel Seidel
- Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
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8
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Entgelmeier LM, García Mancheño O. Activation Modes in Asymmetric Anion-Binding Catalysis. SYNTHESIS-STUTTGART 2022. [DOI: 10.1055/a-1846-6139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Over the past two decades, enantioselective anion-binding catalysis has emerged as a powerful strategy for the induction of chirality in organic transformations. The stereoselectivity is achieved in a range of different reactions by using non-covalent interactions between a chiral catalyst and an ionic substrate or intermediate, and subsequent formation of a chiral contact ion-pair upon anion-binding. This strategy offers vast possibilities in catalysis and the constant development of new reactions has led to various substrate activation approaches. This review provides an overview on the different activation modes in asymmetric anion-binding catalysis by looking at representative examples and recent advances made in this field.
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9
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Schneider C, Dorsch C. Asymmetric Brønsted Acid Catalyzed Cycloadditions of ortho-Quinone Methides and Related Compounds. SYNTHESIS-STUTTGART 2022. [DOI: 10.1055/a-1781-6538] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
AbstractThis review summarizes recent developments in the area of Brønsted acid catalyzed, enantioselective cycloadditions of ortho-quinone methides, ortho-quinone methide imines as well as heterocyclic indole- and pyrrole-based methides. In a straightforward and single-step transformation complex polycyclic N- and O-heterocyclic scaffolds are accessible, with typically good yields and excellent stereocontrol, from simple benzyl and heterobenzyl alcohols upon acid-catalyzed dehydration. The transient precursors are hydrogen-bonded to a chiral Brønsted acid which controls the enantioselectivity of the process.1 Introduction2 Cycloadditions of ortho-Quinone Methides2.1 Brønsted Acid Catalyzed Processes2.2 Cooperative Brønsted Acid/Transition-Metal-Catalyzed Processes3 Cycloadditions of ortho-Quinone Methide Imines4 Cycloadditions of Indolyl-3-methides5 Cycloadditions of Indolyl-2-methides5.1 Brønsted Acid Catalyzed Processes5.2 Cooperative Brønsted Acid/Transition-Metal-Catalyzed Processes6 Cycloadditions of Pyrrolyl-2-methides7 Cycloadditions of Pyrrolyl-3-methides8 Conclusions
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10
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Lei CW, Mu BS, Zhou F, Yu JS, Zhou Y, Zhou J. Organocatalytic enantioselective reactions involving prochiral carbocationic intermediates. Chem Commun (Camb) 2021; 57:9178-9191. [PMID: 34519317 DOI: 10.1039/d1cc03506a] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Since the discovery of carbocations in 1901, the past 120 years have witnessed many marvelous advances in the chemistry of carbocations. The state-of-the-art research in this field is to overcome the intrinsic instability and high reactivity of the prochiral carbocationic intermediates to develop catalytic asymmetric reactions. Such transformations enable the facile synthesis of structurally diverse value-added products from readily available starting materials such as alkenes, alcohols, and carbonyl derivatives, and enjoy high and even perfect atom-economy in most cases. Notably, such allows catalytic stereoconvergent synthesis from racemic substrates and can realize regioselectivity in olefin functionalization reactions complementary to radical processes. With the rapid developments in modern asymmetric organocatalysis, a variety of highly enantioselective protocols evolving prochiral carbocationic intermediates have been achieved by employing three strategies, namely chiral ion-pairing, chiral nucleophile, or chiral carbenium ion strategy. This feature article aims to summarize the exciting advances in this emerging area and briefly showcase the possible mechanisms. The advantages and limitations of each strategy are presented as well as their synthetic applications in the synthesis of natural products or bioactive compounds.
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Affiliation(s)
- Chuan-Wen Lei
- College of Pharmacy, Guizhou University of Traditional Chinese Medicine, Guiyang, 550025, P. R. China.
| | - Bo-Shuai Mu
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, Shanghai Key Laboratory of Green Chemistry and Chemical Processes, East China Normal University, Shanghai, 200062, P. R. China.
| | - Feng Zhou
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, Shanghai Key Laboratory of Green Chemistry and Chemical Processes, East China Normal University, Shanghai, 200062, P. R. China.
| | - Jin-Sheng Yu
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, Shanghai Key Laboratory of Green Chemistry and Chemical Processes, East China Normal University, Shanghai, 200062, P. R. China. .,Key Laboratory of Tropical Medicinal Resource Chemistry of Ministry of Education, Hainan Normal University, Haikou 571158, P. R. China
| | - Ying Zhou
- College of Pharmacy, Guizhou University of Traditional Chinese Medicine, Guiyang, 550025, P. R. China.
| | - Jian Zhou
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, Shanghai Key Laboratory of Green Chemistry and Chemical Processes, East China Normal University, Shanghai, 200062, P. R. China. .,Key Laboratory of Tropical Medicinal Resource Chemistry of Ministry of Education, Hainan Normal University, Haikou 571158, P. R. China
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11
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Lin C, Xing Q, Xie H. A formal intermolecular [4 + 1] cycloaddition reaction of 3-chlorooxindole and o-quinone methides: a facile synthesis of spirocyclic oxindole scaffolds. RSC Adv 2021; 11:18576-18579. [PMID: 35480909 PMCID: PMC9033455 DOI: 10.1039/d1ra01086g] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Accepted: 05/08/2021] [Indexed: 12/11/2022] Open
Abstract
Herein, we developed an efficient and straightforward method for the rapid synthesis of spirocyclic oxindole scaffolds via the [4 + 1] cyclization reaction of 3-chlorooxindole with o-quinone methides (o-QMs), which were generated under mild conditions. The products could be obtained in excellent yields with numerous types of 3-chlorooxindole. This methodology features mild reaction conditions, high atom-economy and broad substrate scope. Herein, we developed an efficient and straightforward method for the rapid synthesis of spirocyclic oxindole scaffolds via the [4 + 1] cyclization reaction of 3-chlorooxindole with o-quinone methides (o-QMs), which were generated under mild conditions.![]()
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Affiliation(s)
- Chao Lin
- Yantai Key Laboratory of Nanomedicine & Advanced Preparations, Yantai Institute of Materia Medica Shandong 264000 China
| | - Qi Xing
- Yantai Key Laboratory of Nanomedicine & Advanced Preparations, Yantai Institute of Materia Medica Shandong 264000 China
| | - Honglei Xie
- Yantai Key Laboratory of Nanomedicine & Advanced Preparations, Yantai Institute of Materia Medica Shandong 264000 China
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12
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Takagi R, Sakai Y, Duong DT. Bis(trifluoromethanesulfonimide) (BSI): Acidity and application to hydrofunctionalization as a Brønsted acid catalyst. Tetrahedron 2021. [DOI: 10.1016/j.tet.2021.132037] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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13
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Kütt A, Tshepelevitsh S, Saame J, Lõkov M, Kaljurand I, Selberg S, Leito I. Strengths of Acids in Acetonitrile. European J Org Chem 2021. [DOI: 10.1002/ejoc.202001649] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- Agnes Kütt
- University of Tartu Institute of Chemistry Ravila 14a 50411 Tartu Estonia
| | | | - Jaan Saame
- University of Tartu Institute of Chemistry Ravila 14a 50411 Tartu Estonia
| | - Märt Lõkov
- University of Tartu Institute of Chemistry Ravila 14a 50411 Tartu Estonia
| | - Ivari Kaljurand
- University of Tartu Institute of Chemistry Ravila 14a 50411 Tartu Estonia
| | - Sigrid Selberg
- University of Tartu Institute of Chemistry Ravila 14a 50411 Tartu Estonia
| | - Ivo Leito
- University of Tartu Institute of Chemistry Ravila 14a 50411 Tartu Estonia
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14
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Ghosh T, Mukherji A, Kancharla PK. Influence of Anion-Binding Schreiner's Thiourea on DMAP Salts: Synergistic Catalysis toward the Stereoselective Dehydrative Glycosylation from 2-Deoxyhemiacetals. J Org Chem 2021; 86:1253-1261. [PMID: 33352053 DOI: 10.1021/acs.joc.0c02473] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Amines are used as additives to facilitate or increase the host-guest chemistry between the thiourea and the anions of Bronsted acids. However, we here demonstrate, for the first time, the synergistic effect of the combination of DMAP/HCl/Schreiner's thiourea in catalyzing dehydrative glycosylation. The variations in the electronic effects of the cationic Bronsted acid part (the protonated DMAP) in the presence of chloride binding Schreiner's thiourea have been discussed using NMR and X-ray crystallographic techniques.
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Affiliation(s)
- Titli Ghosh
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India
| | - Ananya Mukherji
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India
| | - Pavan K Kancharla
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India
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