1
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Continuous production of 3,5,5-trimethylhexanoyl chloride and CFD simulations of single-phase flow in an advanced-flow reactor. J Taiwan Inst Chem Eng 2022. [DOI: 10.1016/j.jtice.2022.104465] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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2
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Lu Z. Fabrication, characterization, and performance of poly (aryl ether nitrile) flat sheet ultrafiltration membranes with polyvinyl pyrrolidone as additives. JOURNAL OF POLYMER ENGINEERING 2022. [DOI: 10.1515/polyeng-2021-0359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Poly(aryl ether nitrile) (PEN) was used to fabricate ultrafiltration membrane via immersion precipitation phase inversion method. The effects of polyvinyl pyrrolidone (PVP) of different molecular weights and concentrations on the structure and performance of PEN membranes were investigated. The membranes were observed by scanning electron microscope, atomic force microscope, equilibrium water content (EWC), porosity (ε), and so on. The membranes were subjected to ultrafiltration characterizations such as pure water flux (PWF), compaction factor (CF), hydraulic permeability (P
m), and bovine serum albumin (BSA) rejection rate. The hydrophilicity was characterized by infrared spectroscopy and contact angle tests. Results showed that molecular weight of PVP had significant effect on PEN membrane formation, which the membrane prepared by PVP-k30 exhibited excellent comprehensive performance. Meanwhile, the concentration of PVP-k30 could effectively control the select-permeability of PEN membrane. With PVP-k30 concentration increased from 7 to 13 wt%, the prepared PEN membranes got higher EWC, ε, CF, and P
m. The PWF increased from 146.5 to 249.1 L m−2 h−1 bar−1, while the overall rejection of BSA remained above 90%. Further increasing the addition amount to 16 wt%, the membrane performance began to decline. Finally, the addition of PVP-k30 could effectively improve the hydrophilicity of prepared PEN membrane surface.
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Affiliation(s)
- Zhaohui Lu
- China Nuclear Power Technology Research Institute Co. Ltd. , Shenzhen , China
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3
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Liu K, Zhao Z, Li H, Li X, Gao X. Development of a novel MW-VLE model for calculation of vapor–liquid equilibrium under microwave irradiation. Chem Eng Sci 2022. [DOI: 10.1016/j.ces.2021.117354] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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4
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Chai J, Nie Y, Wang Z, Cheng L, Liu YG, Wu J. Metal Free Access to Polysubstituted Pyrimidines via Nitrile Activation and [2+2+2] Cycloaddition. Chemistry 2021; 27:17565-17569. [PMID: 34626013 DOI: 10.1002/chem.202103219] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2021] [Indexed: 11/08/2022]
Abstract
Tf2 O mediated intermolecular / intramolecular [2+2+2] cycloaddition between alkynes and nitriles has been developed for efficient construction of polysubstituted pyrimidines and bicyclopyrimidines. In presence of Tf2 O, aza-allene species were generated in situ through nitrile activation and subsequently participated in the [2+2+2] cycloaddition, which was fully supported by deuteration experiments. The reaction had good substrate extensibility with moderate to excellent yield including trimethylsilylalkynes. The method was utilized as a synthetic tool in the preparation of a luminescent metal complex.
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Affiliation(s)
- Jinkui Chai
- Green Catalysis Center and College of Chemistry, Zhengzhou University, Zhengzhou, 450001, P. R. China
| | - Yu Nie
- Green Catalysis Center and College of Chemistry, Zhengzhou University, Zhengzhou, 450001, P. R. China
| | - Zhao Wang
- Henan University of Animal Husbandry and Economy, Zhengzhou, 450001, P. R. China
| | - Li Cheng
- Green Catalysis Center and College of Chemistry, Zhengzhou University, Zhengzhou, 450001, P. R. China
| | - Ying-Guo Liu
- Division of Molecular Catalysis & Synthesis, Henan Institute of Advanced Technology, Zhengzhou University, Zhengzhou, 450001, P. R. China
| | - Junliang Wu
- Green Catalysis Center and College of Chemistry, Zhengzhou University, Zhengzhou, 450001, P. R. China
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5
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Sun M, Yang J, Fu Y, Liang C, Li H, Yan G, Yin C, Yu W, Ma Y, Cheng R, Ye J. Continuous Flow Process for the Synthesis of Betahistine via Aza-Michael-Type Reaction in Water. Org Process Res Dev 2021. [DOI: 10.1021/acs.oprd.0c00543] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Maolin Sun
- Engineering Research Center of Pharmaceutical Process Chemistry, Ministry of Education, School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
- School of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou 510006 China
| | - Jingxin Yang
- Engineering Research Center of Pharmaceutical Process Chemistry, Ministry of Education, School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Youtian Fu
- Engineering Research Center of Pharmaceutical Process Chemistry, Ministry of Education, School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Chaoming Liang
- Engineering Research Center of Pharmaceutical Process Chemistry, Ministry of Education, School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
- School of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou 510006 China
| | - Hong Li
- Engineering Research Center of Pharmaceutical Process Chemistry, Ministry of Education, School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Guoming Yan
- Shanghai Zhongxi Sunve Pharmaceutical Co., Ltd., No. 158 Minle Road, Fengxian District, Shanghai 201419, China
| | - Chao Yin
- Shanghai Zhongxi Sunve Pharmaceutical Co., Ltd., No. 158 Minle Road, Fengxian District, Shanghai 201419, China
| | - Wei Yu
- Shanghai Zhongxi Sunve Pharmaceutical Co., Ltd., No. 158 Minle Road, Fengxian District, Shanghai 201419, China
| | - Yueyue Ma
- Engineering Research Center of Pharmaceutical Process Chemistry, Ministry of Education, School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Ruihua Cheng
- School of Chemical Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Jinxing Ye
- Engineering Research Center of Pharmaceutical Process Chemistry, Ministry of Education, School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
- School of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou 510006 China
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6
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Wang Q, Dai F, Zhang S, Chen C, Yu Y. Fabrication of ultrafiltration membranes by poly (aryl ether nitrile) with poly (ethylene glycol) as additives. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2020; 82:2847-2856. [PMID: 33341775 DOI: 10.2166/wst.2020.529] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
A new kind of flat sheet ultrafiltration membrane was prepared by a promising membrane material, poly (aryl ether nitrile) (PEN), via non-solvent induced phase separation. The effect of solvents, N-methyl-2-pyrrolidone (NMP) and dimethyl acetamide (DMAc), as well as additive of poly (ethylene glycol) (PEG) with different molecular weights on the structure and permeation performance of synthesized membranes were investigated. Comparing with NMP, DMAc is more suitable for the casting solution preparation due to better solubility. A gradually changing pore from sponge-like to finger-like can be observed when PEG was added with DMAc as solvent, while a finger-like pore structure always appears in the NMP system with or without PEG. In both systems, the formation of macrovoids is effectively promoted by the addition of PEG, and higher porosity membranes can be obtained by PEG with higher molecular weight. With the increase of PEG molecular weight from 400 to 10,000 Da, the permeate flux increases from 74.5 to 114.3 L·m-2·h-1 and from 102.0 to 130.8 L·m-2·h-1 under a 100 kPa pressure-driven when NMP and DMAc were used as solvents, respectively. The membranes prepared by DMAc exhibit outstanding rejection of BSA with rejections all above 96.5%.
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Affiliation(s)
- Qi Wang
- Center for Advanced Low-Dimension Materials, State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Material Science and Engineering, Donghua University, Shanghai 201620, China E-mail:
| | - Fengna Dai
- Center for Advanced Low-Dimension Materials, State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Material Science and Engineering, Donghua University, Shanghai 201620, China E-mail:
| | - Shangying Zhang
- Center for Advanced Low-Dimension Materials, State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Material Science and Engineering, Donghua University, Shanghai 201620, China E-mail:
| | - Chunhai Chen
- Center for Advanced Low-Dimension Materials, State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Material Science and Engineering, Donghua University, Shanghai 201620, China E-mail:
| | - Youhai Yu
- Center for Advanced Low-Dimension Materials, State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Material Science and Engineering, Donghua University, Shanghai 201620, China E-mail:
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7
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8
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Znidar D, O’Kearney-McMullan A, Munday R, Wiles C, Poechlauer P, Schmoelzer C, Dallinger D, Kappe CO. Scalable Wolff–Kishner Reductions in Extreme Process Windows Using a Silicon Carbide Flow Reactor. Org Process Res Dev 2019. [DOI: 10.1021/acs.oprd.9b00336] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Desiree Znidar
- Center for Continuous Flow Synthesis and Processing (CCFLOW), Research Center Pharmaceutical Engineering GmbH (RCPE), Inffeldgasse 13, 8010 Graz, Austria
- Institute of Chemistry, University of Graz, NAWI Graz, Heinrichstrasse 28, 8010 Graz, Austria
| | | | - Rachel Munday
- AstraZeneca, Silk Road Business Park, Macclesfield SK10 2NA, United Kingdom
| | | | - Peter Poechlauer
- Patheon Austria GmbH & Co. KG, Sankt-Peter-Straße 25, 4020 Linz, Austria
| | | | - Doris Dallinger
- Center for Continuous Flow Synthesis and Processing (CCFLOW), Research Center Pharmaceutical Engineering GmbH (RCPE), Inffeldgasse 13, 8010 Graz, Austria
- Institute of Chemistry, University of Graz, NAWI Graz, Heinrichstrasse 28, 8010 Graz, Austria
| | - C. Oliver Kappe
- Center for Continuous Flow Synthesis and Processing (CCFLOW), Research Center Pharmaceutical Engineering GmbH (RCPE), Inffeldgasse 13, 8010 Graz, Austria
- Institute of Chemistry, University of Graz, NAWI Graz, Heinrichstrasse 28, 8010 Graz, Austria
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9
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Grbović LM, Pavlović KJ, Jovanović-Šanta SS, Vasiljević BR. Microwave-Assisted Synthesis of Bile Acids Derivatives: An Overview. CURR ORG CHEM 2019. [DOI: 10.2174/1385272823666190213114104] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
:
The first attempts at microwave-assisted (MW) syntheses of bile acid derivatives
were performed in domestic MW appliances. However, the reproducibility of these
syntheses, which were performed in uncontrolled conditions, was very low. In the first
part of this overview, compounds synthesized under such conditions are presented. Consequently,
with the development of MW technology, MW-assisted reactions in MW reactors
became reproducible. Thus, in the second part of this review, syntheses of bile acidsbased
compounds in MW reactors are presented. Among others, publications dealing with
the following topics will be covered:
:
− Chemical transformations of hydroxyl and/or carboxyl functions of bile acids into
esters or amides,
:
− Hydroxyl group oxidations,
:
− Derivatization of oxo-compounds with different nitrogen-containing compounds (e.g. 4-amino-3-
substituted-1H-1,2,4-triazole-5-thiones, thiocarbohydrazides and thiosemicarbazides)
:
Bile acid-based molecular tweezers, capable of stereospecific molecular recognition
:
Reactions of hydroxyl functions to give chlorine derivatives, presenting reactive intermediates in substitution
reactions with N- or O-containing nucleophilic arylhydrazides, urea derivatives, substituted thiadiazoles or
triazoles or amino acid methyl esters, mainly in solvent-free conditions.
:
Some of the synthesized compounds expressed antimicrobial potential and/or good recognition properties as
artificial receptors for specific amino acids or anions.
:
Detailed comparisons between conventional and MW-assisted procedures for chemical transformations of bile
acids are given in most of the presented publications. Based on these results, MW irradiation methods are simpler,
more efficient, cleaner and faster than conventional synthetic methods, meeting the requirements of green
chemistry.
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Affiliation(s)
- Ljubica M. Grbović
- Department of Chemistry, Biochemistry and Environmental Protection, University of Novi Sad, Faculty of Sciences, Trg Dositeja Obradovica 3, 21000 Novi Sad, Serbia
| | - Ksenija J. Pavlović
- Department of Chemistry, Biochemistry and Environmental Protection, University of Novi Sad, Faculty of Sciences, Trg Dositeja Obradovica 3, 21000 Novi Sad, Serbia
| | - Suzana S. Jovanović-Šanta
- Department of Chemistry, Biochemistry and Environmental Protection, University of Novi Sad, Faculty of Sciences, Trg Dositeja Obradovica 3, 21000 Novi Sad, Serbia
| | - Bojana R. Vasiljević
- Department of Chemistry, Biochemistry and Environmental Protection, University of Novi Sad, Faculty of Sciences, Trg Dositeja Obradovica 3, 21000 Novi Sad, Serbia
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10
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Saravanan P, Anbarasan P. Trifluoromethylthiolative 1,2-difunctionalization of alkenes with diselenides and AgSCF3. Chem Commun (Camb) 2019; 55:4639-4642. [DOI: 10.1039/c9cc00815b] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An efficient regioselective difunctionalization of alkenes via trifluoromethylthiolation has been accomplished employing diaryl diselenide and AgSCF3 in the presence of BF3·OEt2.
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Affiliation(s)
- Perumal Saravanan
- Department of Chemistry
- Indian Institute of Technology Madras
- Chennai-600036
- India
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11
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Barham JP, Koyama E, Norikane Y, Ohneda N, Yoshimura T. Microwave Flow: A Perspective on Reactor and Microwave Configurations and the Emergence of Tunable Single‐Mode Heating Toward Large‐Scale Applications. CHEM REC 2018; 19:188-203. [DOI: 10.1002/tcr.201800104] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Accepted: 10/17/2018] [Indexed: 11/06/2022]
Affiliation(s)
- Joshua P. Barham
- Electronics and Photonics Research InstituteNational Institute of Advanced Industrial Science and Technology Tsukuba Central 5, 1-1-1 Higashi Tsukuba, Ibaraki 305-8568 Japan
| | - Emiko Koyama
- Electronics and Photonics Research InstituteNational Institute of Advanced Industrial Science and Technology Tsukuba Central 5, 1-1-1 Higashi Tsukuba, Ibaraki 305-8568 Japan
| | - Yasuo Norikane
- Electronics and Photonics Research InstituteNational Institute of Advanced Industrial Science and Technology Tsukuba Central 5, 1-1-1 Higashi Tsukuba, Ibaraki 305-8568 Japan
| | - Noriyuki Ohneda
- SAIDA FDS, INC. 143-10 Isshiki Yaizu, Shizuoka 425-0054 Japan
| | - Takeo Yoshimura
- SAIDA FDS, INC. 143-10 Isshiki Yaizu, Shizuoka 425-0054 Japan
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12
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Petricci E, Risi C, Ferlin F, Lanari D, Vaccaro L. Avoiding hot-spots in Microwave-assisted Pd/C catalysed reactions by using the biomass derived solvent γ-Valerolactone. Sci Rep 2018; 8:10571. [PMID: 30002506 PMCID: PMC6043498 DOI: 10.1038/s41598-018-28458-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 06/15/2018] [Indexed: 01/19/2023] Open
Abstract
Herein, we report the use of γ-valerolactone as a new biomass-derived reaction medium for microwave assisted organic synthesis. The interaction of this solvent with microwaves and its heating profile under microwave irradiation has been fully characterized for the first time, demonstrating its stability and the applicability in microwave assisted Pd/C catalysed reactions avoiding the arcing phenomena frequently observed in these conditions. The use of γ-valerolactone demonstrated to be compatible with aliphatic and aromatic amines in the hydrogen transfer Pd/C mediated synthesis of benzimidazoles.
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Affiliation(s)
- Elena Petricci
- Università degli Studi di Siena, Dipartimento di Biotecnologie, Chimica e Farmacia, Siena, 53100, Italy.
| | - Caterina Risi
- Università degli Studi di Siena, Dipartimento di Biotecnologie, Chimica e Farmacia, Siena, 53100, Italy
| | - Francesco Ferlin
- Università di Perugia, Laboratory of Green Synthetic Organic Chemistry, Dipartimento di Chimica, Biologia e Biotecnologie, Perugia, 06123, Italy
| | - Daniela Lanari
- Università di Perugia, Dipartimento di Scienze Farmaceutiche, Perugia, 06123, Italy
| | - Luigi Vaccaro
- Università di Perugia, Laboratory of Green Synthetic Organic Chemistry, Dipartimento di Chimica, Biologia e Biotecnologie, Perugia, 06123, Italy.
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13
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Fischer F, Hapke M. Air-Stable CpCo I-Phosphite-Fumarate Precatalyst in Cyclization Reactions: Comparing Different Methods of Energy Supply. European J Org Chem 2018; 2018:3193-3201. [PMID: 30344447 PMCID: PMC6175375 DOI: 10.1002/ejoc.201800196] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Indexed: 11/11/2022]
Abstract
The robust CoI precatalyst [CpCo(P{OEt}3)(trans-MeO2CHC=CHCO2Me)] was investigated in cyclotrimerizations, furnishing benzenes and pyridines from triynes, diynes and nitriles, comparing the influence of different ways of energy supply; namely, irradiation and conventional (thermal) or microwave heating. The precatalyst was found to work under all conditions, including the possibility to catalyze cyclotrimerizations at room temperature under photochemical conditions at longer reaction times. Performance of the reactions in a microwave reactor proved to be the most time-efficient way to rapidly assemble the expected reaction products; however, careful selection of reaction conditions can be required. The synthesis of pyridines and isoquinolines successfully involved the utilization of versatile functionalized nitriles, affording structurally interesting reaction products. Comparison with the known and often applied precatalyst CpCo(CO)2 demonstrated the significantly higher reactivity of the CpCoI-phosphite-olefin precatalyst.
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Affiliation(s)
- Fabian Fischer
- Leibniz‐Institut für Katalyse e.V. an der Universität Rostock (LIKAT)Albert‐Einstein‐Strasse 29a18059RostockGermany
| | - Marko Hapke
- Leibniz‐Institut für Katalyse e.V. an der Universität Rostock (LIKAT)Albert‐Einstein‐Strasse 29a18059RostockGermany
- Institut für Katalyse (INCA)Johannes Kepler Universität LinzAltenberger Strasse 694040LinzAustria
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14
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15
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Koziakov D, Majek M, Jacobi von Wangelin A. Radical Aromatic Trifluoromethylthiolation: Photoredox Catalysis vs. Base Mediation. European J Org Chem 2017. [DOI: 10.1002/ejoc.201701339] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Denis Koziakov
- Institute of Organic Chemistry; University of Regensburg; Germany
| | - Michal Majek
- Institute of Organic Chemistry; University of Regensburg; Germany
| | - Axel Jacobi von Wangelin
- Institute of Organic Chemistry; University of Regensburg; Germany
- Department of Chemistry; University of Hamburg; Martin Luther King Platz 6 20146 Hamburg Germany
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16
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Znidar D, Hone CA, Inglesby P, Boyd A, Kappe CO. Development of a Continuous-Flow Sonogashira Cross-Coupling Protocol using Propyne Gas under Process Intensified Conditions. Org Process Res Dev 2017. [DOI: 10.1021/acs.oprd.7b00160] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- Desiree Znidar
- Institute
of Chemistry, University of Graz, NAWI Graz, Heinrichstrasse 28, 8010 Graz, Austria
| | - Christopher A. Hone
- Institute
of Chemistry, University of Graz, NAWI Graz, Heinrichstrasse 28, 8010 Graz, Austria
- Research Center Pharmaceutical Engineering GmbH (RCPE), Inffeldgasse 13, 8010 Graz, Austria
| | - Phillip Inglesby
- AstraZeneca, Silk Road Business Park, Macclesfield SK10 2NA, United Kingdom
| | - Alistair Boyd
- AstraZeneca, Silk Road Business Park, Macclesfield SK10 2NA, United Kingdom
| | - C. Oliver Kappe
- Institute
of Chemistry, University of Graz, NAWI Graz, Heinrichstrasse 28, 8010 Graz, Austria
- Research Center Pharmaceutical Engineering GmbH (RCPE), Inffeldgasse 13, 8010 Graz, Austria
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17
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Zhao M, Zhao X, Zheng P, Tian Y. Cu-mediated oxidative trifluoromethylthiolation of arylboronic acids with (bpy)CuSCF3. J Fluor Chem 2017. [DOI: 10.1016/j.jfluchem.2017.01.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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18
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Prieto P, de la Hoz A, Díaz-Ortiz A, Rodríguez AM. Understanding MAOS through computational chemistry. Chem Soc Rev 2017; 46:431-451. [DOI: 10.1039/c6cs00393a] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Computational chemistry may explain and rationalize the impact of microwave irradiation in organic synthesis.
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Affiliation(s)
- P. Prieto
- Departamento de Química Orgánica
- Facultad de Ciencias y Tecnologías Químicas
- Universidad de Castilla-La Mancha
- 13071 Ciudad Real
- Spain
| | - A. de la Hoz
- Departamento de Química Orgánica
- Facultad de Ciencias y Tecnologías Químicas
- Universidad de Castilla-La Mancha
- 13071 Ciudad Real
- Spain
| | - A. Díaz-Ortiz
- Departamento de Química Orgánica
- Facultad de Ciencias y Tecnologías Químicas
- Universidad de Castilla-La Mancha
- 13071 Ciudad Real
- Spain
| | - A. M. Rodríguez
- Department of Chemical Sciences
- University of Naples Federico II
- Naples 80126
- Italy
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19
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Bana P, Greiner I. Investigation of Selective Microwave Heating Phenomena in the Reactions of 2-Substituted Pyridines. Aust J Chem 2017. [DOI: 10.1071/ch16643] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Debated selective microwave heating effects were investigated in a rearrangement and a benzylation reaction involving 2-substituted pyridines. An accurate, reproducible comparison technique and simultaneous temperature measurement using both external infrared and internal fibre optic sensors were utilized. The experimental details of the benzylation reaction were thoroughly addressed to resolve the inconsistencies that have been discussed previously in the literature. Hidden inhomogeneities in temperature and concentration were revealed within the reaction mixtures during microwave heating, which could be prevented by the modification of the vessel wall using an inert fluoropolymer liner. Instead of the previously proposed microscopic thermal microwave effect, the enhanced reaction rate could be explained by macroscopic-scale localized heating in the boundary layers close to the vessel surface in the microwave-heated experiment.
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20
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Bu MJ, Lu GP, Cai C. Transition-metal-free electrophilic trifluoromethylthiolation with sodium trifluoromethanesulfinate at room temperature. Org Chem Front 2017. [DOI: 10.1039/c6qo00622a] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A transition-metal-free direct trifluoromethylthiolation of C(sp2)–H bonds could be achieved with commercially available CF3SO2Na under room temperature.
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Affiliation(s)
- Mei-jie Bu
- Chemical Engineering College
- Nanjing University of Science and Technology
- Nanjing
- P. R. China
| | - Guo-ping Lu
- Chemical Engineering College
- Nanjing University of Science and Technology
- Nanjing
- P. R. China
| | - Chun Cai
- Chemical Engineering College
- Nanjing University of Science and Technology
- Nanjing
- P. R. China
- Key Laboratory of Organofluorine Chemistry
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21
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Obermayer D, Znidar D, Glotz G, Stadler A, Dallinger D, Kappe CO. Design and Performance Validation of a Conductively Heated Sealed-Vessel Reactor for Organic Synthesis. J Org Chem 2016; 81:11788-11801. [DOI: 10.1021/acs.joc.6b02242] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- David Obermayer
- Institute
of Chemistry, University of Graz, NAWI Graz, Heinrichstrasse 28, 8010 Graz, Austria
| | - Desiree Znidar
- Institute
of Chemistry, University of Graz, NAWI Graz, Heinrichstrasse 28, 8010 Graz, Austria
| | - Gabriel Glotz
- Institute
of Chemistry, University of Graz, NAWI Graz, Heinrichstrasse 28, 8010 Graz, Austria
| | - Alexander Stadler
- Department
of Analytical and Synthetic Chemistry, Anton Paar GmbH, Anton-Paar-Strasse
20, 8054 Graz, Austria
| | - Doris Dallinger
- Institute
of Chemistry, University of Graz, NAWI Graz, Heinrichstrasse 28, 8010 Graz, Austria
| | - C. Oliver Kappe
- Institute
of Chemistry, University of Graz, NAWI Graz, Heinrichstrasse 28, 8010 Graz, Austria
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22
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Pawar HS, Wagh AS, Lali AM. Triethylamine: a potential N-base surrogate for pyridine in Knoevenagel condensation of aromatic aldehydes and malonic acid. NEW J CHEM 2016. [DOI: 10.1039/c5nj03125g] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Triethyl amine was successfully examined as a potent N-base surrogate for Knoevenagel condensation to produce cinnamic acids without compromising product yield.
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Affiliation(s)
- Hitesh S. Pawar
- DBT-ICT Centre for Energy Biosciences
- Institute of Chemical Technology
- Mumbai
- India
| | - Adhirath S. Wagh
- DBT-ICT Centre for Energy Biosciences
- Institute of Chemical Technology
- Mumbai
- India
| | - Arvind M. Lali
- DBT-ICT Centre for Energy Biosciences
- Institute of Chemical Technology
- Mumbai
- India
- Department of Chemical Engineering
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23
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Saravanan P, Anbarasan P. Copper-Catalyzed Trifluoromethylthiolation of Di(hetero)aryl-λ3-iodanes: Mechanistic Insight and Application to Synthesis of (Hetero)Aryl Trifluoromethyl Sulfides. Adv Synth Catal 2015. [DOI: 10.1002/adsc.201500606] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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24
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Rokade BV, Gadde K, Prabhu KR. Copper-Catalyzed Direct Transformation of Secondary Allylic and Benzylic Alcohols into Azides and Amides: An Efficient Utility of Azide as a Nitrogen Source. European J Org Chem 2015. [DOI: 10.1002/ejoc.201500010] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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25
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Kashima K, Ishii M, Tanaka K. Synthesis of Pyridylphosphonates by Rhodium-Catalyzed [2+2+2] Cycloaddition of 1,6- and 1,7-Diynes with Diethyl Phosphorocyanidate. European J Org Chem 2015. [DOI: 10.1002/ejoc.201403452] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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26
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Ashley B, Lovingood DD, Chiu YC, Gao H, Owens J, Strouse GF. Specific effects in microwave chemistry explored through reactor vessel design, theory, and spectroscopy. Phys Chem Chem Phys 2015; 17:27317-27. [DOI: 10.1039/c5cp03961d] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The interaction of microwave photons is directly measured using dielectric spectroscopy and heating rates for improved understanding of MW chemistry.
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Affiliation(s)
- Bridgett Ashley
- Department of Chemistry and Biochemistry
- Florida State University
- Tallahassee, USA
- Air Force Civil Engineer Center
- , USA
| | | | - Yu-Che Chiu
- Department of Physics
- Florida State University
- Tallahassee, USA
| | - Hanwei Gao
- Department of Physics
- Florida State University
- Tallahassee, USA
| | | | - Geoffrey F. Strouse
- Department of Chemistry and Biochemistry
- Florida State University
- Tallahassee, USA
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27
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Rodríguez AM, Prieto P, de la Hoz A, Díaz-Ortiz A, García JI. The issue of 'molecular radiators' in microwave-assisted reactions. Computational calculations on ring closing metathesis (RCM). Org Biomol Chem 2014; 12:2436-45. [PMID: 24599220 DOI: 10.1039/c3ob42536c] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A DFT computational mechanistic study of the ring closing metathesis (RCM) reaction of diallyl ether or N,N-diallyl-p-toluenesulfonamide catalyzed by a second generation Grubbs-type ruthenium carbene complex has been carried out. This study was performed at the PCM(CH2Cl2)-B3LYP/6-311+G(2d,p)//B3LYP/SDD theory level. The aim of this work was to shed light on the influence that microwave irradiation has on these reactions and to gain insight into the so-called 'molecular radiator' effect. The outcomes obtained indicate that thermal effects induced by microwave irradiation decrease the catalytic induction period. The presence of a polar reagent and/or polar species in the reaction that increases the polarity of the medium may enhance this thermal effect.
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Affiliation(s)
- A M Rodríguez
- Departamento de Química Orgánica, Facultad de Ciencias y Tecnologías Químicas, Universidad de Castilla-La Mancha, 13071 Ciudad Real, Spain.
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28
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Hayden S, Studentschnig AFH, Schober S, Kappe CO. A Critical Investigation on the Occurrence of Microwave Effects in Emulsion Polymerizations. MACROMOL CHEM PHYS 2014. [DOI: 10.1002/macp.201400279] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Stephan Hayden
- Christian Doppler Laboratory for Microwave Chemistry and Institute of Chemistry; University of Graz, NAWI Graz; Heinrichstrasse 28 A-8010 Graz Austria
| | | | - Sigurd Schober
- Institute of Chemistry; University of Graz, NAWI Graz; Heinrichstrasse 28 A-8010 Graz Austria
| | - C. Oliver Kappe
- Christian Doppler Laboratory for Microwave Chemistry and Institute of Chemistry; University of Graz, NAWI Graz; Heinrichstrasse 28 A-8010 Graz Austria
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29
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Xu XH, Matsuzaki K, Shibata N. Synthetic methods for compounds having CF3-S units on carbon by trifluoromethylation, trifluoromethylthiolation, triflylation, and related reactions. Chem Rev 2014; 115:731-64. [PMID: 25121343 DOI: 10.1021/cr500193b] [Citation(s) in RCA: 836] [Impact Index Per Article: 83.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Xiu-Hua Xu
- Department of Nanopharmaceutical Science and Department of Frontier Materials, Nagoya Institute of Technology , Gokiso, Showa-ku, Nagoya 466-8555, Japan
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30
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Rosana MR, Hunt J, Ferrari A, Southworth TA, Tao Y, Stiegman AE, Dudley GB. Microwave-Specific Acceleration of a Friedel–Crafts Reaction: Evidence for Selective Heating in Homogeneous Solution. J Org Chem 2014; 79:7437-50. [DOI: 10.1021/jo501153r] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- Michael R. Rosana
- Department of Chemistry and
Biochemistry, Florida State University, Tallahassee, Florida 32306-4390, United States
| | - Jacob Hunt
- Department of Chemistry and
Biochemistry, Florida State University, Tallahassee, Florida 32306-4390, United States
| | - Anthony Ferrari
- Department of Chemistry and
Biochemistry, Florida State University, Tallahassee, Florida 32306-4390, United States
| | - Taylor A. Southworth
- Department of Chemistry and
Biochemistry, Florida State University, Tallahassee, Florida 32306-4390, United States
| | - Yuchuan Tao
- Department of Chemistry and
Biochemistry, Florida State University, Tallahassee, Florida 32306-4390, United States
| | - Albert E. Stiegman
- Department of Chemistry and
Biochemistry, Florida State University, Tallahassee, Florida 32306-4390, United States
| | - Gregory B. Dudley
- Department of Chemistry and
Biochemistry, Florida State University, Tallahassee, Florida 32306-4390, United States
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31
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Pinder JL, Davis RE, Charrier JD. A facile, one-pot procedure for the formation of benzimidazoles from esters using DABAL-Me3, an air stable source of AlMe3. Tetrahedron Lett 2014. [DOI: 10.1016/j.tetlet.2014.06.026] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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32
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Zhu YJ, Chen F. Microwave-assisted preparation of inorganic nanostructures in liquid phase. Chem Rev 2014; 114:6462-555. [PMID: 24897552 DOI: 10.1021/cr400366s] [Citation(s) in RCA: 317] [Impact Index Per Article: 31.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Ying-Jie Zhu
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences , Shanghai 200050, People's Republic of China
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33
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Kappe CO. How to measure reaction temperature in microwave-heated transformations. Chem Soc Rev 2013; 42:4977-90. [PMID: 23443140 DOI: 10.1039/c3cs00010a] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
High-speed microwave chemistry has attracted considerable attention in the past two decades with new and innovative applications in organic and peptide synthesis, polymer chemistry, material sciences, nanotechnology and biochemical processes continuously being reported in the literature. In particular the introduction of benchtop single-mode microwave reactors just over ten years ago has revolutionized the way many scientists today perform reactions in the laboratory. Unfortunately, the accurate measurement of reaction temperature in these devices is far from being trivial and requires both a basic understanding of microwave dielectric heating effects and use of appropriate temperature monitoring devices. In this tutorial review frequently occurring problems in the determination of accurate reaction temperatures in single-mode microwave reactors are discussed.
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Affiliation(s)
- C Oliver Kappe
- Christian Doppler Laboratory for Microwave Chemistry and Institute of Chemistry, Karl-Franzens-University Graz, Heinrichstrasse 28, A-8010 Graz, Austria.
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34
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Obermayer D, Damm M, Kappe CO. Simulating Microwave Chemistry in a Resistance-Heated Autoclave Made of Semiconducting Silicon Carbide Ceramic. Chemistry 2013; 19:15827-30. [DOI: 10.1002/chem.201303638] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2013] [Indexed: 12/16/2022]
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35
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Kappe CO. Unraveling the mysteries of microwave chemistry using silicon carbide reactor technology. Acc Chem Res 2013; 46:1579-87. [PMID: 23463987 DOI: 10.1021/ar300318c] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
In the past few years, the use of microwave energy to heat chemical reactions has become an increasingly popular theme in the scientific community. This nonclassical heating technique has slowly progressed from a laboratory curiosity to an established method commonly used both in academia and in industry. Because of its efficiency, microwave heating dramatically reduces reaction times (from days and hours to minutes and seconds) and improves product purities or material properties among other advantages. Since the early days of microwave chemistry, researchers have observed rate-accelerations and, in some cases, altered product distributions as compared with reactions carried out using classical oil-bath heating. As a result, researchers have speculated that so-called specific or nonthermal microwave effects could be responsible for these differences. Much of the debate has centered on the question of whether the electromagnetic field can exert a direct influence on a chemical transformation outside of the simple macroscopic change in bulk reaction temperature. In 2009, our group developed a relatively simple "trick" that allows us to rapidly evaluate whether an observed effect seen in a microwave-assisted reaction results from a purely thermal phenomenon, or involves specific or nonthermal microwave effects. We use a microwave reaction vessel made from silicon carbide (SiC) ceramic. Because of its high microwave absorptivity, the vessel shields its contents from the electromagnetic field. As a result, we can easily mimic a conventionally heated autoclave experiment inside a microwave reactor under carefully controlled reaction conditions. The switch from an almost microwave transparent glass (Pyrex) to a strongly microwave absorbing SiC reaction vial under otherwise identical reaction conditions (temperature profiles, pressure, stirring speed) then allows us to carefully evaluate the influence of the electromagnetic field on the particular chemical transformation. Over the past five years we have subjected a wide variety of chemical transformations, including organic reactions, preparations of inorganic nanoparticles, and the hydrolysis of proteins, to the "SiC test." In nearly all of the studied examples, we obtained identical results from reactions carried out in Pyrex vials and those carried out in SiC vials. The data obtained from these investigations confirm that in the overwhelming majority of cases a bulk temperature phenomenon drives the enhancements in microwave chemistry and that the electromagnetic field has no direct influence on the reaction pathway.
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Affiliation(s)
- C. Oliver Kappe
- Christian Doppler Laboratory for Microwave Chemistry (CDLMC) and Institute of Chemistry, Karl-Franzens-University Graz, Heinrichstrasse 28, A-8010 Graz, Austria
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36
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Dudley GB, Stiegman AE, Rosana MR. Correspondence on Microwave Effects in Organic Synthesis. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201301539] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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37
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Dudley GB, Stiegman AE, Rosana MR. Correspondence on Microwave Effects in Organic Synthesis. Angew Chem Int Ed Engl 2013; 52:7918-23. [DOI: 10.1002/anie.201301539] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2013] [Indexed: 11/09/2022]
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38
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Cantillo D, Moghaddam MM, Kappe CO. Hydrazine-mediated Reduction of Nitro and Azide Functionalities Catalyzed by Highly Active and Reusable Magnetic Iron Oxide Nanocrystals. J Org Chem 2013; 78:4530-42. [DOI: 10.1021/jo400556g] [Citation(s) in RCA: 123] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- David Cantillo
- Christian Doppler
Laboratory for Microwave Chemistry
(CDLMC) and Institute of Chemistry, Karl-Franzens-University Graz, Heinrichstrasse 28, A-8010 Graz, Austria
| | - Mojtaba Mirhosseini Moghaddam
- Christian Doppler
Laboratory for Microwave Chemistry
(CDLMC) and Institute of Chemistry, Karl-Franzens-University Graz, Heinrichstrasse 28, A-8010 Graz, Austria
| | - C. Oliver Kappe
- Christian Doppler
Laboratory for Microwave Chemistry
(CDLMC) and Institute of Chemistry, Karl-Franzens-University Graz, Heinrichstrasse 28, A-8010 Graz, Austria
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39
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In situ preparation of silver nanocomposites on cellulosic fibers – Microwave vs. conventional heating. Carbohydr Polym 2013; 94:677-86. [DOI: 10.1016/j.carbpol.2013.01.077] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2012] [Accepted: 01/25/2013] [Indexed: 12/11/2022]
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40
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Mixing with microwaves: solvent-free and catalyst-free synthesis of pyrazoles and diazepines. Tetrahedron Lett 2013. [DOI: 10.1016/j.tetlet.2013.01.029] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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41
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Obermayer D, Damm M, Kappe CO. Design and evaluation of improved magnetic stir bars for single-mode microwave reactors. Org Biomol Chem 2013; 11:4949-56. [DOI: 10.1039/c3ob40790j] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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42
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Moghaddam MM, Baghbanzadeh M, Keilbach A, Kappe CO. Microwave-assisted synthesis of CdSe quantum dots: can the electromagnetic field influence the formation and quality of the resulting nanocrystals? NANOSCALE 2012; 4:7435-7442. [PMID: 23085887 DOI: 10.1039/c2nr32441e] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Microwave-assisted syntheses of colloidal nanocrystals (NCs), in particular CdSe quantum dots (QDs), have gained considerable attention due to unique opportunities provided by microwave dielectric heating. The extensive use of microwave heating and the frequently suggested specific microwave effects, however, pose questions about the role of the electromagnetic field in both the formation and quality of the produced QDs. In this work a one-pot protocol for the tunable synthesis of monodisperse colloidal CdSe NCs using microwave dielectric heating under carefully controlled conditions is introduced. CdSe QDs are fabricated using selenium dioxide as a selenium precursor, 1-octadecene as a solvent and reducing agent, cadmium alkyl carboxylates or alkyl phosphonates as cadmium sources, 1,2-hexadecanediol to stabilize the cadmium complex and oleic acid to stabilize the resulting CdSe QDs. Utilizing the possibilities of microwave heating technology in combination with accurate online temperature control the influence of different reaction parameters such as reaction temperature, ramp and hold times, and the timing and duration of oleic acid addition have been carefully investigated. Optimum results were obtained by performing the reaction at 240 °C applying a 5 min ramp time, 2 min hold time before oleic acid addition, 90 s for oleic acid addition, and a 5 min hold time after oleic acid addition (8.5 min overall holding at 240 °C). By using different cadmium complexes in the microwave protocol CdSe QDs with a narrow size distribution can be obtained in different sizes ranging from 0.5-4 nm by simply changing the cadmium source. The QDs were characterized by TEM, HRTEM, UV-Vis, and photoluminescence methods and the size distribution was monitored by SAXS. Control experiments involving conventional conductive heating under otherwise identical conditions ensuring the same heating and cooling profiles, stirring rates, and reactor geometries demonstrate that the electromagnetic field has no influence on the generated CdSe QDs. The resulting CdSe NCs prepared using either conductive or microwave dielectric heating exhibited the same primary crystallite size, shape, quantum yield and size distribution regardless of the heating mode.
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Affiliation(s)
- Mojtaba Mirhosseini Moghaddam
- Christian Doppler Laboratory for Microwave Chemistry (CDLMC), Institute of Chemistry, Karl Franzens University Graz, Heinrichstrasse 28, A-8010 Graz, Austria
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43
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Kappe CO, Pieber B, Dallinger D. Microwave Effects in Organic Synthesis: Myth or Reality? Angew Chem Int Ed Engl 2012; 52:1088-94. [DOI: 10.1002/anie.201204103] [Citation(s) in RCA: 396] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2012] [Indexed: 11/07/2022]
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44
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Kappe CO, Pieber B, Dallinger D. Mikrowelleneffekte in der organischen Synthese - Mythos oder Wirklichkeit? Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201204103] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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45
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Hayden S, Damm M, Kappe CO. On the Importance of Accurate Internal Temperature Measurements in the Microwave Dielectric Heating of Viscous Systems and Polymer Synthesis. MACROMOL CHEM PHYS 2012. [DOI: 10.1002/macp.201200449] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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46
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Damm M, Nusshold C, Cantillo D, Rechberger GN, Gruber K, Sattler W, Kappe CO. Can electromagnetic fields influence the structure and enzymatic digest of proteins? A critical evaluation of microwave-assisted proteomics protocols. J Proteomics 2012; 75:5533-43. [PMID: 22889711 PMCID: PMC3484400 DOI: 10.1016/j.jprot.2012.07.043] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2012] [Revised: 07/27/2012] [Accepted: 07/27/2012] [Indexed: 10/31/2022]
Abstract
This study reevaluates the putative advantages of microwave-assisted tryptic digests compared to conventionally heated protocols performed at the same temperature. An initial investigation of enzyme stability in a temperature range of 37-80 °C demonstrated that trypsin activity declines sharply at temperatures above 60 °C, regardless if microwave dielectric heating or conventional heating is employed. Tryptic digests of three proteins of different size (bovine serum albumin, cytochrome c and β-casein) were thus performed at 37 °C and 50 °C using both microwave and conventional heating applying accurate internal fiber-optic probe reaction temperature measurements. The impact of the heating method on protein degradation and peptide fragment generation was analyzed by SDS-PAGE and MALDI-TOF-MS. Time-dependent tryptic digestion of the three proteins and subsequent analysis of the corresponding cleavage products by MALDI-TOF provided virtually identical results for both microwave and conventional heating. In addition, the impact of electromagnetic field strength on the tertiary structure of trypsin and BSA was evaluated by molecular mechanics calculations. These simulations revealed that the applied field in a typical laboratory microwave reactor is 3-4 orders of magnitude too low to induce conformational changes in proteins or enzymes.
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Affiliation(s)
- Markus Damm
- Christian Doppler Laboratory for Microwave Chemistry (CDLMC) and Institute of Chemistry, Karl-Franzens-University Graz, Heinrichstrasse 28/I, A-8010 Graz, Austria
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47
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Ma Z, Ni F, Woo GHC, Lo SM, Roveto PM, Schaus SE, Snyder JK. An intramolecular inverse electron demand Diels-Alder approach to annulated α-carbolines. Beilstein J Org Chem 2012; 8:829-40. [PMID: 23015831 PMCID: PMC3388871 DOI: 10.3762/bjoc.8.93] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2012] [Accepted: 05/08/2012] [Indexed: 11/23/2022] Open
Abstract
Intramolecular inverse electron demand cycloadditions of isatin-derived 1,2,4-triazines with acetylenic dienophiles tethered by amidations or transesterifications proceed in excellent yields to produce lactam- or lactone-fused α-carbolines. Beginning with various isatins and alkynyl dienophiles, a pilot-scale library of eighty-eight α-carbolines was prepared by using this robust methodology for biological evaluation.
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Affiliation(s)
- Zhiyuan Ma
- Department of Chemistry and the Center for Chemical Methodology and Library Development (CMLD-BU), Boston University, 590 Commonwealth Avenue, Boston, Massachusetts 02215
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48
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Xia F, Zhao ZL, Liu PN. Sulfuric acid catalyzed addition of β-dicarbonyl compounds to alcohols under conventional heating and microwave-assisted conditions. Tetrahedron Lett 2012. [DOI: 10.1016/j.tetlet.2012.03.104] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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49
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50
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Rodriguez AM, Cebrián C, Prieto P, García JI, de la Hoz A, Díaz-Ortiz Á. DFT Studies on Cobalt-Catalyzed Cyclotrimerization Reactions: The Mechanism and Origin of Reaction Improvement under Microwave Irradiation. Chemistry 2012; 18:6217-24. [DOI: 10.1002/chem.201103560] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2011] [Indexed: 11/06/2022]
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