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Marčeková M, Caletková O, Kalníková R, Litecká M, Moncol’ J, Jakubec P. Synthetic Chameleon Turns into Oximes, Nitrones, and Hydroxylamines when Exposed to Blue Light. ACS OMEGA 2024; 9:14262-14268. [PMID: 38559917 PMCID: PMC10976417 DOI: 10.1021/acsomega.3c10041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 02/25/2024] [Accepted: 02/29/2024] [Indexed: 04/04/2024]
Abstract
A metal-free, user-friendly photochemical transformation of nitroalkanes to oximes, nitrones, and hydroxylamines has been developed. The visible-light-induced reactions are catalyzed by the readily available photoredox organocatalyst 4CzIPN and use inexpensive amines as reductants. Broad in scope and tolerant of multiple functional groups and heterocycles, the transformation proceeds under mild conditions. Its synthetic potential was demonstrated in the formal total synthesis of amathaspiramide F. A basic insight into the reaction mechanism was gained with the help of an NMR study.
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Affiliation(s)
- Michaela Marčeková
- Faculty
of Chemical and Food Technology, Slovak
University of Technology in Bratislava, Radlinského 9, Bratislava 812 37, Slovakia
| | - Ol’ga Caletková
- Faculty
of Chemical and Food Technology, Slovak
University of Technology in Bratislava, Radlinského 9, Bratislava 812 37, Slovakia
| | - Radka Kalníková
- Faculty
of Chemical and Food Technology, Slovak
University of Technology in Bratislava, Radlinského 9, Bratislava 812 37, Slovakia
| | - Miroslava Litecká
- Institute
of Inorganic Chemistry Czech Academy of Sciences, Řež 250
68, Czech Republic
| | - Ján Moncol’
- Faculty
of Chemical and Food Technology, Slovak
University of Technology in Bratislava, Radlinského 9, Bratislava 812 37, Slovakia
| | - Pavol Jakubec
- Faculty
of Chemical and Food Technology, Slovak
University of Technology in Bratislava, Radlinského 9, Bratislava 812 37, Slovakia
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Némethová V, Krištofíková D, Mečiarová M, Šebesta R. Asymmetric Organocatalysis Under Mechanochemical Conditions. CHEM REC 2023:e202200283. [PMID: 36703542 DOI: 10.1002/tcr.202200283] [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: 12/06/2022] [Revised: 01/05/2023] [Indexed: 01/28/2023]
Abstract
Asymmetric organocatalysis is a robust methodology providing access to numerous valuable compounds while having green chemistry principles in mind. The realization of organocatalytic transformation under solvent-free mechanochemical conditions brings additional benefits in terms of yields, selectivities, and, last but not least overall improved sustainability. This overview describes developments in the use of mechanochemistry as a vehicle for asymmetric organocatalytic transformations. The material is organized according to main catalytic activation modes, starting with covalent activation and proceeding to non-covalent activation modes. The advantages of mechanochemical organocatalytic reactions are particularly highlighted, but in some cases also, limitations are mentioned. Possibilities for target compound synthesis are also discussed.
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Affiliation(s)
- Viktória Némethová
- Department of Organic Chemistry, Faculty of Natural Sciences, Comenius University in Bratislava, Mlynská dolina, Ilkovičova 6, 842 15, Bratislava, Slovakia
| | - Dominika Krištofíková
- Department of Organic Chemistry, Faculty of Natural Sciences, Comenius University in Bratislava, Mlynská dolina, Ilkovičova 6, 842 15, Bratislava, Slovakia
| | - Mária Mečiarová
- Department of Organic Chemistry, Faculty of Natural Sciences, Comenius University in Bratislava, Mlynská dolina, Ilkovičova 6, 842 15, Bratislava, Slovakia
| | - Radovan Šebesta
- Department of Organic Chemistry, Faculty of Natural Sciences, Comenius University in Bratislava, Mlynská dolina, Ilkovičova 6, 842 15, Bratislava, Slovakia
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3
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Williams MTJ, Morrill LC, Browne DL. Mechanochemical Organocatalysis: Do High Enantioselectivities Contradict What We Might Expect? CHEMSUSCHEM 2022; 15:e202102157. [PMID: 34767693 PMCID: PMC9300213 DOI: 10.1002/cssc.202102157] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 11/09/2021] [Indexed: 05/10/2023]
Abstract
Ball mills input energy to samples by pulverising the contents of the jar. Each impact on the sample or wall of the jar results in an instantaneous transmission of energy in the form of a temperature and pressure increase (volume reduction). Conversely, enantioselective organocatalytic reactions proceed through perceived delicate and well-organised transition states. Does there exist a dichotomy in the idea of enantioselective mechanochemical organocatalysis? This Review provides a survey of the literature reporting the combination of organocatalytic reactions with mechanochemical ball milling conditions. Where possible, direct comparisons of stirred in solution, stirred neat and ball milled processes are drawn with a particular focus on control of stereoselectivity.
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Affiliation(s)
- Matthew T. J. Williams
- Cardiff Catalysis InstituteSchool of ChemistryCardiff UniversityPark PlaceCardiffCF10 3ATUK
| | - Louis C. Morrill
- Cardiff Catalysis InstituteSchool of ChemistryCardiff UniversityPark PlaceCardiffCF10 3ATUK
| | - Duncan L. Browne
- Department of Pharmaceutical and Biological ChemistrySchool of PharmacyUniversity College London29–39 Brunswick Square, BloomsburyLondonWC1N 1AXUK
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Efficacy of Selenourea Organocatalysts in Asymmetric Michael Reactions under Standard and Solvent-Free Conditions. Molecules 2021; 26:molecules26237303. [PMID: 34885885 PMCID: PMC8658871 DOI: 10.3390/molecules26237303] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2021] [Revised: 11/26/2021] [Accepted: 11/29/2021] [Indexed: 11/18/2022] Open
Abstract
By varying the steric and electronic surroundings of the hydrogen-bonding motif, the novel chiral Cinchona-alkaloid based selenoureas were developed. Acting as bifunctional catalysts, they were applied in the Michael reactions of dithiomalonate and nitrostyrene providing chiral adducts with up to 96% ee. The asymmetric Michael–-hemiacetalization reaction of benzylidene pyruvate and dimedone, performed with the assistance of 5 mol% of selenoureas, furnished the product with up to 93% ee and excellent yields. The effectiveness of the new hydrogen-bond donors was also proved in solvent-free reactions under ball mill conditions, supporting the sustainability of the devised catalytic protocol.
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Čmelová P, Vargová D, Šebesta R. Hybrid Peptide-Thiourea Catalyst for Asymmetric Michael Additions of Aldehydes to Heterocyclic Nitroalkenes. J Org Chem 2021; 86:581-592. [PMID: 33258590 DOI: 10.1021/acs.joc.0c02251] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Bifunctional organocatalysis combining covalent and noncovalent activation is presented. The hybrid peptide-thiourea catalyst features a N-terminal proline moiety for aldehyde activation and a thiourea unit for electrophile activation. This catalyst effectively promotes asymmetric Michael additions of aldehydes to challenging but biologically relevant heterocycle-containing nitroalkenes. The catalyst can be used under solvent-free conditions. Spectroscopic and density functional theory studies elucidate the catalyst structure and mode of action.
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Affiliation(s)
- Patrícia Čmelová
- Department of Organic Chemistry, Faculty of Natural Sciences, Comenius University in Bratislava, Mlynská dolina, Ilkovičova 6, 842 15 Bratislava, Slovakia
| | - Denisa Vargová
- Department of Organic Chemistry, Faculty of Natural Sciences, Comenius University in Bratislava, Mlynská dolina, Ilkovičova 6, 842 15 Bratislava, Slovakia
| | - Radovan Šebesta
- Department of Organic Chemistry, Faculty of Natural Sciences, Comenius University in Bratislava, Mlynská dolina, Ilkovičova 6, 842 15 Bratislava, Slovakia
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Schöbel JH, Liang W, Wöll D, Bolm C. Mechanochemical Synthesis of 1,2,6-Thiadiazine 1-Oxides from Sulfonimidamides and the Fluorescence Properties of the Products. J Org Chem 2020; 85:15760-15766. [PMID: 33225705 DOI: 10.1021/acs.joc.0c02599] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
A solvent-free mechanochemical synthesis for 1,2,6-thiadiazine 1-oxides starting from NH-sulfonimidamides and propargyl ketones has been developed. Lewis acids affect these one-pot aza-Michael-addition/cyclization/dehydration reaction sequences. The photophysical properties of the resulting heterocyclic sulfonimidamide derivatives were characterized.
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Affiliation(s)
- Jan-Hendrik Schöbel
- Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, D-52074 Aachen, Germany
| | - Wenjing Liang
- Institute of Physical Chemistry, RWTH Aachen University, Landoltweg 2, D-52074 Aachen, Germany
| | - Dominik Wöll
- Institute of Physical Chemistry, RWTH Aachen University, Landoltweg 2, D-52074 Aachen, Germany
| | - Carsten Bolm
- Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, D-52074 Aachen, Germany
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Krištofíková D, Modrocká V, Mečiarová M, Šebesta R. Green Asymmetric Organocatalysis. CHEMSUSCHEM 2020; 13:2828-2858. [PMID: 32141177 DOI: 10.1002/cssc.202000137] [Citation(s) in RCA: 70] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 03/05/2020] [Indexed: 06/10/2023]
Abstract
Asymmetric organocatalysis is becoming one of the main tools for the synthesis of chiral compounds that are needed as medicines, crop protection agents, and other bioactive molecules. It can be effectively combined with various green chemistry methodologies. Intensification techniques, such as ball milling, flow, high pressure, or light, bring not only higher yields, faster reactions, and easier product isolation, but also new reactivities. More sustainable reaction media, such as ionic liquids, deep eutectic solvents, green solvent alternatives, and water, also considerably enhance the sustainability profile of many organocatalytic reactions.
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Affiliation(s)
- Dominika Krištofíková
- Department of Organic Chemistry, Faculty of Natural Sciences, Comenius University in Bratislava, Mlynska dolina, Ilkovicova 6, 842 15, Bratislava, Slovakia
| | - Viktória Modrocká
- Department of Organic Chemistry, Faculty of Natural Sciences, Comenius University in Bratislava, Mlynska dolina, Ilkovicova 6, 842 15, Bratislava, Slovakia
| | - Mária Mečiarová
- Department of Organic Chemistry, Faculty of Natural Sciences, Comenius University in Bratislava, Mlynska dolina, Ilkovicova 6, 842 15, Bratislava, Slovakia
| | - Radovan Šebesta
- Department of Organic Chemistry, Faculty of Natural Sciences, Comenius University in Bratislava, Mlynska dolina, Ilkovicova 6, 842 15, Bratislava, Slovakia
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8
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Nicholson WI, Seastram AC, Iqbal SA, Reed‐Berendt BG, Morrill LC, Browne DL. N-Heterocyclic Carbene Acyl Anion Organocatalysis by Ball-Milling. CHEMSUSCHEM 2020; 13:131-135. [PMID: 31774627 PMCID: PMC6972762 DOI: 10.1002/cssc.201902346] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Indexed: 05/05/2023]
Abstract
The ability to conduct N-heterocyclic carbene-catalysed acyl anion chemistry under ball-milling conditions is reported for the first time. This process has been exemplified through applications to intermolecular-benzoin, intramolecular-benzoin, intermolecular-Stetter and intramolecular-Stetter reactions including asymmetric examples and demonstrates that this mode of mechanistically complex organocatalytic reaction can operate under solvent-minimised conditions.
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Affiliation(s)
- William I. Nicholson
- Cardiff Catalysis InstituteSchool of ChemistryCardiff UniversityPark PlaceCardiffCF10 3ATUnited Kingdom
| | - Alex C. Seastram
- Cardiff Catalysis InstituteSchool of ChemistryCardiff UniversityPark PlaceCardiffCF10 3ATUnited Kingdom
| | - Saqib A. Iqbal
- Cardiff Catalysis InstituteSchool of ChemistryCardiff UniversityPark PlaceCardiffCF10 3ATUnited Kingdom
| | - Benjamin G. Reed‐Berendt
- Cardiff Catalysis InstituteSchool of ChemistryCardiff UniversityPark PlaceCardiffCF10 3ATUnited Kingdom
| | - Louis C. Morrill
- Cardiff Catalysis InstituteSchool of ChemistryCardiff UniversityPark PlaceCardiffCF10 3ATUnited Kingdom
| | - Duncan L. Browne
- Cardiff Catalysis InstituteSchool of ChemistryCardiff UniversityPark PlaceCardiffCF10 3ATUnited Kingdom
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9
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Tan D, Loots L, Friščić T. Towards medicinal mechanochemistry: evolution of milling from pharmaceutical solid form screening to the synthesis of active pharmaceutical ingredients (APIs). Chem Commun (Camb) 2018; 52:7760-81. [PMID: 27185190 DOI: 10.1039/c6cc02015a] [Citation(s) in RCA: 197] [Impact Index Per Article: 32.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
This overview highlights the emergent area of mechanochemical reactions for making active pharmaceutical ingredients (APIs), and covers the latest advances in the recently established area of mechanochemical screening and synthesis of pharmaceutical solid forms, specifically polymorphs, cocrystals, salts and salt cocrystals. We also provide an overview of the most recent developments in pharmaceutical uses of mechanochemistry, including real-time reaction monitoring, techniques for polymorph control and approaches for continuous manufacture using twin screw extrusion, and more. Most importantly, we show how the overlap of previously unrelated areas of mechanochemical screening for API solid forms, organic synthesis by milling, and mechanochemical screening for molecular recognition, enables the emergence of a new research discipline in which different aspects of pharmaceutical and medicinal chemistry are addressed through mechanochemistry rather than through conventional solution-based routes. The emergence of such medicinal mechanochemistry is likely to have a strong impact on future pharmaceutical and medicinal chemistry, as it offers not only access to materials and reactivity that are sometimes difficult or even impossible to access from solution, but can also provide a general answer to the demands of the pharmaceutical industry for cleaner, safer and efficient synthetic solutions.
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Affiliation(s)
- Davin Tan
- Department of Chemistry, McGill University, 801 Sherbrooke St. W, H3A 0B8 Montreal, Canada.
| | - Leigh Loots
- Department of Chemistry, McGill University, 801 Sherbrooke St. W, H3A 0B8 Montreal, Canada.
| | - Tomislav Friščić
- Department of Chemistry, McGill University, 801 Sherbrooke St. W, H3A 0B8 Montreal, Canada.
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Affiliation(s)
- Davin Tan
- Department of Chemistry; McGill University; 801 Sherbrooke St.W. H3A0B8 Montreal Canada
| | - Tomislav Friščić
- Department of Chemistry; McGill University; 801 Sherbrooke St.W. H3A0B8 Montreal Canada
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Husch T, Seebach D, Beck AK, Reiher M. Rigorous Conformational Analysis of Pyrrolidine Enamines with Relevance to Organocatalysis. Helv Chim Acta 2017. [DOI: 10.1002/hlca.201700182] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Tamara Husch
- Laboratorium für Physikalische Chemie ETH Zürich Vladimir‐Prelog‐Weg 3 8093 Zürich Switzerland
| | - Dieter Seebach
- Laboratorium für Organische Chemie ETH Zürich Vladimir‐Prelog‐Weg 2 8093 Zürich Switzerland
| | - Albert K. Beck
- Laboratorium für Organische Chemie ETH Zürich Vladimir‐Prelog‐Weg 2 8093 Zürich Switzerland
| | - Markus Reiher
- Laboratorium für Physikalische Chemie ETH Zürich Vladimir‐Prelog‐Weg 3 8093 Zürich Switzerland
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12
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Veverková E, Modrocká V, Šebesta R. Organocatalyst Efficiency in the α-Aminoxylation and α-Hydrazination of Carbonyl Derivatives in Aqueous Media or in a Ball-Mill. European J Org Chem 2017. [DOI: 10.1002/ejoc.201601357] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Eva Veverková
- Department of Organic Chemistry; Faculty of Natural Sciences; Comenius University in Bratislava; Mlynska dolina, Ilkovicova 6 84215 Bratislava Slovakia
| | - Viktória Modrocká
- Department of Organic Chemistry; Faculty of Natural Sciences; Comenius University in Bratislava; Mlynska dolina, Ilkovicova 6 84215 Bratislava Slovakia
| | - Radovan Šebesta
- Department of Organic Chemistry; Faculty of Natural Sciences; Comenius University in Bratislava; Mlynska dolina, Ilkovicova 6 84215 Bratislava Slovakia
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13
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Li Y, Ibsen L, Jørgensen KA. Formal Asymmetric α-Alkenylation of Aldehydes and the Synthetic Application toward Forming α-exo-Methylene-γ-butyrolactones and Skipped Dienes. Org Lett 2017; 19:1200-1203. [DOI: 10.1021/acs.orglett.7b00254] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Yang Li
- Department of Chemistry, Aarhus University, Langelandsgade
140, DK-8000 Aarhus
C, Denmark
| | - Lise Ibsen
- Department of Chemistry, Aarhus University, Langelandsgade
140, DK-8000 Aarhus
C, Denmark
| | - Karl Anker Jørgensen
- Department of Chemistry, Aarhus University, Langelandsgade
140, DK-8000 Aarhus
C, Denmark
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Rightmire NR, Bruns DL, Hanusa TP, Brennessel WW. Mechanochemical Influence on the Stereoselectivity of Halide Metathesis: Synthesis of Group 15 Tris(allyl) Complexes. Organometallics 2016. [DOI: 10.1021/acs.organomet.6b00151] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Nicholas R. Rightmire
- Department
of Chemistry, Vanderbilt University, Nashville, Tennessee 37235, United States
| | - David L. Bruns
- Department
of Chemistry, Vanderbilt University, Nashville, Tennessee 37235, United States
| | - Timothy P. Hanusa
- Department
of Chemistry, Vanderbilt University, Nashville, Tennessee 37235, United States
| | - William W. Brennessel
- Department
of Chemistry, University of Rochester, Rochester, New York 14627, United States
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15
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Polindara-García LA, Juaristi E. Synthesis of Ugi 4-CR and Passerini 3-CR Adducts under Mechanochemical Activation. European J Org Chem 2016. [DOI: 10.1002/ejoc.201501371] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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17
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Jörres M, Aceña JL, Soloshonok VA, Bolm C. Asymmetric Carbon-Carbon Bond Formation under Solventless Conditions in Ball Mills. ChemCatChem 2015. [DOI: 10.1002/cctc.201500102] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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Machuca E, Rojas Y, Juaristi E. Synthesis and Evaluation of (S)-Proline-Containing α,β-Dipeptides as Organocatalysts in Solvent-Free Asymmetric Aldol Reactions Under Ball-Milling Conditions. ASIAN J ORG CHEM 2014. [DOI: 10.1002/ajoc.201402170] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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19
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Mihali V, Foschi F, Penso M, Pozzi G. Chemoselective Synthesis ofN-Protected Alkoxyprolines under Specific Solvation Conditions. European J Org Chem 2014. [DOI: 10.1002/ejoc.201402429] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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20
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Hestericová M, Šebesta R. Higher enantioselectivities in thiourea-catalyzed Michael additions under solvent-free conditions. Tetrahedron 2014. [DOI: 10.1016/j.tet.2013.12.029] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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21
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Jia C, Chen D, Zhang C, Zhang Q, Cao B, Zhao Z. Mechanosynthesis of γ-nitro dicarbonyl compounds via CaCl2-catalyzed Michael addition. Tetrahedron 2013. [DOI: 10.1016/j.tet.2013.06.089] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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22
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Seebach D, Sun X, Ebert MO, Schweizer WB, Purkayastha N, Beck AK, Duschmalé J, Wennemers H, Mukaiyama T, Benohoud M, Hayashi Y, Reiher M. Stoichiometric Reactions of Enamines Derived from Diphenylprolinol Silyl Ethers with Nitro Olefins and Lessons for the Corresponding Organocatalytic Conversions - a Survey. Helv Chim Acta 2013. [DOI: 10.1002/hlca.201300079] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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23
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Veverková E, Liptáková L, Veverka M, Šebesta R. Asymmetric Mannich reactions catalyzed by proline and 4-hydroxyproline derived organocatalysts in the presence of water. ACTA ACUST UNITED AC 2013. [DOI: 10.1016/j.tetasy.2013.03.016] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Chauhan P, Chimni SS. Mechanochemistry assisted asymmetric organocatalysis: A sustainable approach. Beilstein J Org Chem 2012; 8:2132-41. [PMID: 23243475 PMCID: PMC3520570 DOI: 10.3762/bjoc.8.240] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2012] [Accepted: 11/28/2012] [Indexed: 11/23/2022] Open
Abstract
Ball-milling and pestle and mortar grinding have emerged as powerful methods for the development of environmentally benign chemical transformations. Recently, the use of these mechanochemical techniques in asymmetric organocatalysis has increased. This review highlights the progress in asymmetric organocatalytic reactions assisted by mechanochemical techniques.
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Affiliation(s)
- Pankaj Chauhan
- U.G.C. Sponsored Centre for Advance Studies in Chemistry, Department of Chemistry Guru Nanak Dev University, Amritsar, 143005, India
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