1
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Kumar Sharma S. The Importance of Organocatalysis (Asymmetric and Non‐Asymmetric) in Agrochemicals. ChemistrySelect 2023. [DOI: 10.1002/slct.202300204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/30/2023]
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2
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Sun Y, Qiao Z, Li D, Ni J, Wang J, Wang P, Song N, Li M. Correction to “Access to 6-Deoxy-heptose Constructs by One Carbon Homologation of Hexoses with Malononitrile: Divergent Synthesis of Campylobacter jejuni Strain 81-176 Capsular Trisaccharide Repeating Unit Derivatives”. Org Lett 2022; 24:9168. [DOI: 10.1021/acs.orglett.2c03928] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/07/2022]
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3
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Pasha MA, Anebouselvy K, Ramachary DB. Lawsone as synthon in the catalytic asymmetric reactions. Tetrahedron 2022. [DOI: 10.1016/j.tet.2022.132793] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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4
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Zhu T, Zhang XJ, Zhou Z, Xu Z, Ma M, Zhao B. Synthesis of functionalized malononitriles via Fe-catalysed hydrogen atom transfers of alkenes. Org Biomol Chem 2022; 20:1480-1487. [PMID: 35103271 DOI: 10.1039/d1ob02332b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Described herein is a practical and convenient approach that enabled radical-mediated conjugate addition of unreactive alkenes to electron-deficient alkenes leading to a broad range of substituted malononitriles. These reactions are believed to proceed by Fe-catalysed hydrogen atom transfer (HAT) onto the alkenes affording carbon-centered radical intermediates with Markovnikov selectivity, followed by the capture of electron-deficient alkenes. We explored this synthesis approach under mild conditions with high efficiency and broad substrate scope and the utility is highlighted by the further synthetic transformations of the obtained substituted malononitriles.
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Affiliation(s)
- Tianxiang Zhu
- Department of Chemistry and Materials Science, College of Science, Nanjing Forestry University, Nanjing 210037, China.
| | - Xue-Jun Zhang
- Department of Orthopedic Surgery, Zhongda Hospital, School of Medicine, Southeast University, Nanjing, China
| | - Zihan Zhou
- Department of Chemistry and Materials Science, College of Science, Nanjing Forestry University, Nanjing 210037, China.
| | - Zitong Xu
- Department of Chemistry and Materials Science, College of Science, Nanjing Forestry University, Nanjing 210037, China.
| | - Mengtao Ma
- Department of Chemistry and Materials Science, College of Science, Nanjing Forestry University, Nanjing 210037, China.
| | - Binlin Zhao
- Department of Chemistry and Materials Science, College of Science, Nanjing Forestry University, Nanjing 210037, China.
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5
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Danehchin M, Esmaeili AA. Biomimetic hydrogenation of electron deficient olefins using in situ generated 2-arylbenzimidazoline: synthesis of novel 3-benzylbenzo[4,5]thiazolo[3,2-a]pyrimidin-4-ones. Mol Divers 2021; 26:1191-1199. [PMID: 34117585 DOI: 10.1007/s11030-021-10246-y] [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: 03/05/2021] [Accepted: 06/03/2021] [Indexed: 11/28/2022]
Abstract
In the present study, 2-Arylbenzimidazoline generated in situ from reaction of aromatic aldehydes and o-phenylenediamine used as biomimetic reductive agents for reductive alkylation of 2-hydroxy-4H-benzo[4,5]thiazolo[3,2-a]pyrimidin-4-one for synthesis of novel 3-benzyl-2-hydroxy-4H-benzo[4,5]thiazolo[3,2-a]pyrimidin-4-ones is described. The main benefits of this protocol include simplicity, reaction mildness, high yield, easy work up, and simple purification. The molecular structures were characterized by IR spectrophotometry, mass spectrometry, NMR spectroscopy, and elemental analysis.
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Affiliation(s)
- Maryam Danehchin
- Department of Chemistry, Faculty of Science, Ferdowsi University of Mashhad, Mashhad, 9177948974, Iran
| | - Abbas Ali Esmaeili
- Department of Chemistry, Faculty of Science, Ferdowsi University of Mashhad, Mashhad, 9177948974, Iran.
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6
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Sharma A, Saraswat A. Overview on cumulative synthetic approaches for chalcone based functionalized scaffolds. J INDIAN CHEM SOC 2021. [DOI: 10.1016/j.jics.2021.100028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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7
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Peraka S, Hussain A, Ramachary DB. Modular Access to Chiral 2,3-Dihydrofurans and 3,4-Dihydro-2H-pyrans by Stereospecific Activation of Formylcyclopropanes through Combination of Organocatalytic Reductive Coupling and Lewis-Acid-Catalyzed Annulative Ring-Opening Reactions. J Org Chem 2018; 83:9795-9817. [DOI: 10.1021/acs.joc.8b01315] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Swamy Peraka
- Catalysis Laboratory, School of Chemistry, University of Hyderabad, Hyderabad 500 046, India
| | - Akram Hussain
- Catalysis Laboratory, School of Chemistry, University of Hyderabad, Hyderabad 500 046, India
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8
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Ramachary DB, Reddy PS, Gujral J. Construction of 2-Thiabicyclo[3.3.1]nonanes by Organocatalytic Asymmetric Formal [3+3] Cycloaddition. European J Org Chem 2018. [DOI: 10.1002/ejoc.201701617] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
| | - P. Srinivasa Reddy
- Catalysis Laboratory; School of Chemistry; University of Hyderabad; 500 046 Hyderabad- India
| | - Jagjeet Gujral
- Catalysis Laboratory; School of Chemistry; University of Hyderabad; 500 046 Hyderabad- India
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9
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Wang R, Hou M, Xu Z, Tan L, Zhong C, Zhu L. A new red fluorophore with aggregation enhanced emission by an unexpected “One-step” protocol. RSC Adv 2018; 8:18327-18333. [PMID: 35541101 PMCID: PMC9080569 DOI: 10.1039/c8ra00955d] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Accepted: 05/09/2018] [Indexed: 01/20/2023] Open
Abstract
In this work, a triphenylamine-benzothiadiazole-based new fluorophore is obtained from a facile “one-step” protocol. A possible reduction mechanism is proposed, and an amine containing α-H plays a key role in the reduction reaction. The resultant product A1H2 exhibits bright red emission in solid state, with an absolute quantum yield of 44.5%. Aggregation induced emission enhancement of A1H2 is also observed with the increased water fraction in THF-H2O mixture. The nanoparticles of A1H2 reveal good stability and biocompatibility, which are successfully applied in cellular cytoplasm imaging. Compound A1H2 was synthesized via the reductive Knoevenagel alkylation, whose nanoparticles exhibit bright red emission in aqueous solution.![]()
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Affiliation(s)
- Rui Wang
- Chongqing Key Laboratory for Advanced Materials and Technologies of Clean Energy
- Faculty of Materials & Energy
- Southwest University
- Chongqing 400715
- P. R. China
| | - Meili Hou
- Chongqing Key Laboratory for Advanced Materials and Technologies of Clean Energy
- Faculty of Materials & Energy
- Southwest University
- Chongqing 400715
- P. R. China
| | - Zhigang Xu
- Chongqing Key Laboratory for Advanced Materials and Technologies of Clean Energy
- Faculty of Materials & Energy
- Southwest University
- Chongqing 400715
- P. R. China
| | - Luxi Tan
- School of Chemistry and Chemical Engineering
- Chongqing University
- Chongqing 401331
- P. R. China
| | - Cheng Zhong
- Department of Chemistry
- Hubei Key Lab on Organic and Polymeric Optoelectronic Materials
- Wuhan University
- Wuhan 430072
- P. R. China
| | - Linna Zhu
- Chongqing Key Laboratory for Advanced Materials and Technologies of Clean Energy
- Faculty of Materials & Energy
- Southwest University
- Chongqing 400715
- P. R. China
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10
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Jiang G, Liu M, Fang D, Tan P, Huang M, Zhou T, Jiang Z, Xu Z, Wang Z. A base promoted one pot solvent free version of the Ramachary reductive coupling/alkylation reaction for the synthesis of 2,2-disubstituted ethyl cyanoacetates. RSC Adv 2018; 8:8961-8964. [PMID: 35539882 PMCID: PMC9078616 DOI: 10.1039/c8ra00326b] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Accepted: 02/19/2018] [Indexed: 12/14/2022] Open
Abstract
An N,N-diisopropylethylamine promoted solvent-free Ramachary reductive coupling/alkylation (RRC/A) reaction for the synthesis of 2,2-disubstituted ethyl cyanoacetates has been developed. A series of 2,2-disubstituted ethyl cyanoacetates were synthesized in one pot by the RRC/A reaction of commercially available aldehydes, ethyl cyanacetates, alkyl halides and Hantzsch ester. A solvent free two step multicomponent reaction has also been developed for the preparation of 2,2-dialkylated malononitriles and 2,2-dialkylated 4-nitrophenyl acetonitriles. All the designed RRC/A products could be easily obtained with good yields by these methods. An N,N-diisopropylethylamine promoted solvent-free Ramachary reductive coupling/alkylation (RRC/A) reaction for the synthesis of 2,2-disubstituted ethyl cyanoacetates has been developed.![]()
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Affiliation(s)
| | - Min Liu
- Department of Chemistry
- Xihua University
- Chengdu
- China
| | - Dongmei Fang
- Chengdu Institute of Biology
- Chinese Academy of Sciences
- Chengdu
- China
| | - Ping Tan
- Department of Chemistry
- Xihua University
- Chengdu
- China
| | - Min Huang
- Department of Chemistry
- Xihua University
- Chengdu
- China
| | - Taiping Zhou
- Department of Chemistry
- Xihua University
- Chengdu
- China
| | - Zhenju Jiang
- Department of Chemistry
- Xihua University
- Chengdu
- China
| | - Zhihong Xu
- Department of Chemistry
- Xihua University
- Chengdu
- China
| | - Zhouyu Wang
- Department of Chemistry
- Xihua University
- Chengdu
- China
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11
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Kummer DA, Cummings MD, Abad M, Barbay J, Castro G, Wolin R, Kreutter KD, Maharoof U, Milligan C, Nishimura R, Pierce J, Schalk-Hihi C, Spurlino J, Urbanski M, Venkatesan H, Wang A, Woods C, Xue X, Edwards JP, Fourie AM, Leonard K. Identification and structure activity relationships of quinoline tertiary alcohol modulators of RORγt. Bioorg Med Chem Lett 2017; 27:2047-2057. [DOI: 10.1016/j.bmcl.2017.02.044] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Revised: 02/10/2017] [Accepted: 02/14/2017] [Indexed: 12/22/2022]
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12
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Denmark SE, Ibrahim MYS, Ambrosi A. Room Temperature, Reductive Alkylation of Activated Methylene Compounds: Carbon–Carbon Bond Formation Driven by the Rhodium-Catalyzed Water–Gas Shift Reaction. ACS Catal 2016. [DOI: 10.1021/acscatal.6b03183] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Scott E. Denmark
- Roger Adams Laboratory, Department
of Chemistry, University of Illinois, Urbana, Illinois 61801, United States
| | - Malek Y. S. Ibrahim
- Roger Adams Laboratory, Department
of Chemistry, University of Illinois, Urbana, Illinois 61801, United States
| | - Andrea Ambrosi
- Roger Adams Laboratory, Department
of Chemistry, University of Illinois, Urbana, Illinois 61801, United States
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13
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Wong YC, Kao TT, Huang JK, Jhang YW, Chou MC, Shia KS. Manganese(III)-Catalyzed Oxidative Cyclization of Aryl 1-Cyanoalk-5-ynyl Ketone Systems: A Convenient and General Approach to Cyclopenta[b]naphthalene Derivatives. Adv Synth Catal 2014. [DOI: 10.1002/adsc.201400257] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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14
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Ramachary DB, Venkaiah C, Reddy YV. High-yielding sequential one-pot synthesis of chiral and achiral α-substituted acrylates via a metal-free reductive coupling reaction. Org Biomol Chem 2014; 12:5400-6. [PMID: 24934801 DOI: 10.1039/c4ob00667d] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A general process for the high-yielding synthesis of substituted chiral and achiral α-substituted acrylates was achieved through the sequential one-pot combination of a metal-free reductive coupling reaction followed by an Eschenmoser methylenation. The proline catalyzed reaction of Meldrum's acid, aldehydes and Hantzsch ester followed by methylenation was successful with Eschenmoser's salt in the presence of an alcohol solvent. Herein, we have shown the high-yielding synthesis of privileged building blocks from chiral/achiral α-substituted acrylates and shown them to be very good intermediates in the pharmaceuticals and natural products synthesis.
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15
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Yang YQ, Lu Z. A Convenient Heterogeneous Reduction of Knoevenagel Product by Hantzsch Ester and Its Development into Reductive Alkylation of Malononitrile. CHINESE J CHEM 2014. [DOI: 10.1002/cjoc.201400144] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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16
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Wong YC, Kao TT, Yeh YC, Hsieh BS, Shia KS. Palladium(0)/Copper(I)-Catalyzed Tandem Cyclization of Aryl 1-Cyanoalk-5-ynyl Ketone System: Rapid Assembly of Cyclopenta[b]naphthalene and Benzo[b]fluorene Derivatives. Adv Synth Catal 2013. [DOI: 10.1002/adsc.201300107] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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17
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Tite T, Sabbah M, Levacher V, Brière JF. Organocatalysed decarboxylative protonation process from Meldrum's acid: enantioselective synthesis of isoxazolidinones. Chem Commun (Camb) 2013; 49:11569-71. [DOI: 10.1039/c3cc47695b] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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18
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Ramachary DB, Sakthidevi R, Reddy PS. Direct organocatalytic stereoselective transfer hydrogenation of conjugated olefins of steroids. RSC Adv 2013. [DOI: 10.1039/c3ra41519h] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
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19
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Wong YC, Tseng CT, Kao TT, Yeh YC, Shia KS. Tandem cyclization of α-cyano α-alkynyl aryl ketones induced by tert-butyl hydroperoxide and tetrabutylammonium iodide. Org Lett 2012. [PMID: 23190145 DOI: 10.1021/ol3028972] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The radical cascade protocol of the α-cyano α-TMS/aryl-capped alkynyl aryl ketones promoted by tert-butyl hydroperoxide under catalysis with tetrabutylammonium iodide in refluxing benzene has been developed, leading to the construction of a variety of highly functionalized [6,6,5] tricyclic frameworks in an efficient manner.
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Affiliation(s)
- Ying-Chieh Wong
- Institute of Biotechnology and Pharmaceutical Research, National Health Research Institutes, Miaoli County 35053, Taiwan, R. O. C
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20
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Zheng C, You SL. Transfer hydrogenation with Hantzsch esters and related organic hydride donors. Chem Soc Rev 2012; 41:2498-518. [PMID: 22282764 DOI: 10.1039/c1cs15268h] [Citation(s) in RCA: 438] [Impact Index Per Article: 36.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In recent years, Hantzsch esters and their related organic hydride donors have been widely utilized in biomimetic approaches of asymmetric transfer hydrogenation (ATH) reactions. Various compounds containing C=C, C=N and C=O unsaturated functionalities could be reduced in the presence of organocatalysts or transition metal complexes, affording versatile chiral building blocks in high yields and excellent enantioselectivities under mild conditions. In this critical review, recent advances in this area are summarized and classified according to unsaturated functional groups being reduced and catalytic systems employed (91 references).
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Affiliation(s)
- Chao Zheng
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China
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21
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Huang X, Wen YH, Zhou FT, Chen C, Xu DC, Xie JW. Organocatalytic and direct asymmetric vinylogous Michael addition of 3-cyano-4-methylcoumarins to α,β-unsaturated ketones. Tetrahedron Lett 2010. [DOI: 10.1016/j.tetlet.2010.10.055] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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22
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Ramachary DB, Jain S. Sequential one-pot combination of multi-component and multi-catalysis cascade reactions: an emerging technology in organic synthesis. Org Biomol Chem 2010; 9:1277-300. [PMID: 21120241 DOI: 10.1039/c0ob00611d] [Citation(s) in RCA: 219] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Creating sequential one-pot combinations of multi-component reactions (MCRs) and multi-catalysis cascade (MCC) reactions is a challenging task that has already emerged as a new technology in synthetic organic chemistry. Through one-pot sequential combination of MCRs/MCC reactions, the chemical products (fine chemicals, agrochemicals and pharmaceuticals) that add value to our lives can be produced with less waste and greater economic benefits. Within this Emerging Area, we describe our recent developments and designs for sequential one-pot MCRs/MCC reactions to facilitate their realization as biomimetics in organic chemistry.
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23
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Kumar A, Sharma S, Tripathi VD, Srivastava S. Synthesis of chalcones and flavanones using Julia–Kocienski olefination. Tetrahedron 2010. [DOI: 10.1016/j.tet.2010.09.089] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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24
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Mudhar H, Witty A. One-pot conversion of alkyl aldehydes into substituted propanoic acids via Knoevenagel condensation with Meldrum’s acid. Tetrahedron Lett 2010. [DOI: 10.1016/j.tetlet.2010.07.054] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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25
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Amancha PK, Liu HJ, Ly TW, Shia KS. General Approach to 2,3-Dibenzyl-γ-butyrolactone Lignans: Application to the Total Synthesis of (±)-5′-Methoxyyatein, (±)-5′-Methoxyclusin, and (±)-4′-Hydroxycubebinone. European J Org Chem 2010. [DOI: 10.1002/ejoc.201000318] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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26
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Ramachary DB, Mondal R, Venkaiah C. Rapid two-step synthesis of drug-like polycyclic substances by sequential multi-catalysis cascade reactions. Org Biomol Chem 2010; 8:321-5. [DOI: 10.1039/b920152a] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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27
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Samai S, Nandi GC, Singh P, Singh M. l-Proline: an efficient catalyst for the one-pot synthesis of 2,4,5-trisubstituted and 1,2,4,5-tetrasubstituted imidazoles. Tetrahedron 2009. [DOI: 10.1016/j.tet.2009.10.019] [Citation(s) in RCA: 206] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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28
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Xie JW, Huang X, Fan LP, Xu DC, Li XS, Su H, Wen YH. Efficient Method for the Synthesis of Optically Active 2-Amino-2-chromene Derivatives via One-Pot Tandem Reactions. Adv Synth Catal 2009. [DOI: 10.1002/adsc.200900579] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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29
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Pandey J, Anand N, Tripathi RP. l-Proline catalyzed multicomponent reaction of 3,4-dihydro-(2H)-pyran, urea/thiourea, and aldehydes: diastereoselective synthesis of hexahydropyrano pyrimidinones (thiones). Tetrahedron 2009. [DOI: 10.1016/j.tet.2009.09.002] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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30
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Ramachary D, Sakthidevi R. Direct Catalytic Asymmetric Synthesis of Highly Functionalized 2-Methylchroman-2,4-diols via Barbas-List Aldol Reaction. Chemistry 2009; 15:4516-22. [DOI: 10.1002/chem.200900066] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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31
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Ramachary DB, Narayana VV, Prasad MS, Ramakumar K. High-yielding synthesis of Nefopam analogues (functionalized benzoxazocines) by sequential one-pot cascade operations. Org Biomol Chem 2009; 7:3372-8. [DOI: 10.1039/b910397j] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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32
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Ramachary DB, Ramakumar K, Narayana VV. Amino acid-catalyzed cascade [3+2]-cycloaddition/hydrolysis reactions based on the push-pull dienamine platform: synthesis of highly functionalized NH-1,2,3-triazoles. Chemistry 2008; 14:9143-7. [PMID: 18767077 DOI: 10.1002/chem.200801325] [Citation(s) in RCA: 178] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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33
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Ramachary DB, Kishor M. Direct amino acid-catalyzed cascade biomimetic reductive alkylations: application to the asymmetric synthesis of Hajos-Parrish ketone analogues. Org Biomol Chem 2008; 6:4176-87. [PMID: 18972048 DOI: 10.1039/b807999d] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A direct amino acid-catalyzed chemo- and enantioselective process for the double cascade synthesis of highly substituted 2-alkyl-cyclopentane-1,3-diones, 2-alkyl-3-methoxy-cyclopent-2-enones and Hajos-Parrish (H-P) ketone analogs is presented via reductive alkylation chemistry. For the first time, we have developed a single-step alkylation of cyclopentane-1,3-dione with aldehydes/ketones and a Hantzsch ester through an organocatalytic reductive alkylation strategy. A direct combination of amino acid-catalyzed cascade olefination-hydrogenation and cascade Robinson annulations of cyclopentane-1,3-dione, aldehydes/ketones, a Hantzsch ester and methyl vinyl ketone furnished the highly functionalized H-P ketone analogues in good to high yields and with excellent enantioselectivities. Many of the reductive alkylation products have shown direct applications in pharmaceutical chemistry.
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34
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Ramachary DB, Narayana VV, Ramakumar K. Direct ionic liquid promoted organocatalyzed diazo-transfer reactions: diversity-oriented synthesis of diazo-compounds. Tetrahedron Lett 2008. [DOI: 10.1016/j.tetlet.2008.02.159] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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35
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Ramachary DB, Kishor M, Reddy YV. Development of Pharmaceutical Drugs, Drug Intermediates and Ingredients by Using Direct Organo-Click Reactions. European J Org Chem 2008. [DOI: 10.1002/ejoc.200701014] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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36
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Ramachary DB, Sakthidevi R. Combining multi-catalysis and multi-component systems for the development of one-pot asymmetric reactions: stereoselective synthesis of highly functionalized bicyclo[4.4.0]decane-1,6-diones. Org Biomol Chem 2008; 6:2488-92. [DOI: 10.1039/b806243a] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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37
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Ramachary DB, Reddy YV, Kishor M. Multi-catalysis reactions: direct organocatalytic sequential one-pot synthesis of highly functionalized cyclopenta[b]chromen-1-ones. Org Biomol Chem 2008; 6:4188-97. [DOI: 10.1039/b812551a] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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38
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Ramachary DB, Reddy YV, Prakash BV. Double cascade reactions based on the Barbas dienamine platform: highly stereoselective synthesis of functionalized cyclohexanes for cardiovascular agents. Org Biomol Chem 2008; 6:719-26. [DOI: 10.1039/b718122a] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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39
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Kotsuki H, Ikishima H, Okuyama A. Organocatalytic Asymmetric Synthesis Using Proline and Related Molecules. Part 2. HETEROCYCLES 2008. [DOI: 10.3987/rev-07-621] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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40
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41
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Ramachary DB, Kishor M, Reddy GB. Development of drug intermediates by using direct organocatalytic multi-component reactions. Org Biomol Chem 2006; 4:1641-6. [PMID: 16633553 DOI: 10.1039/b602696f] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Novel, economic and environmentally friendly one-pot three-component Knoevenagel/hydrogenation (K/H) and four-component Knoevenagel/hydrogenation/alkylation (K/H/A) reactions of ketones, CH-acids, dihydropyridines and alkyl halides using proline and proline/metal carbonate catalysis, respectively, have been developed. Many of the products of these K/H and K/H/A reactions have direct applications in pharmaceutical chemistry.
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Ramachary DB, Reddy GB. Towards organo-click reactions: development of pharmaceutical ingredients by using direct organocatalytic bio-mimetic reductions. Org Biomol Chem 2006; 4:4463-8. [PMID: 17268640 DOI: 10.1039/b612611a] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Economic and environmentally friendly bio-mimetic one-pot three and four-component Knoevenagel-hydrogenation (K-H), five-component Knoevenagel-hydrogenation-alkylation (K-H-A) and six-component Knoevenagel-hydrogenation-alkylation-Huisgen cycloaddition (K-H-A-HC) reactions of aldehydes, CH-acids, o-phenylenediamine, alkyl halides and azides using proline, proline-metal carbonate and proline-metal carbonate-Cu(I)-catalysis, respectively have been developed. Many of K-H and K-H-A compounds have direct application in pharmaceutical chemistry.
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