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Fantozzi N, Volle JN, Porcheddu A, Virieux D, García F, Colacino E. Green metrics in mechanochemistry. Chem Soc Rev 2023; 52:6680-6714. [PMID: 37691600 DOI: 10.1039/d2cs00997h] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/12/2023]
Abstract
The development of new green methodologies and their broader adoption for promoting sustainable development in chemistry laboratories and industry play a significant role in society, due to the economic importance of chemistry and its widespread presence in everyday life. Therefore, a sustainable approach to chemistry contributes to the well-being of the worldwide population and complies with the United Nations Sustainable Development Goals (UN SDGs) and the European Green Deal. The review highlights how batch and continuous mechanochemical methods are an eco-friendly approach for organic synthesis, with a lower environmental footprint in most cases, compared to solution-based procedures. The assessment is objectively based on the use of green metrics (e.g., atom and real atom economy, E-factor, process mass intensity, material parameter recovery, Eco-scale, stoichiometric factor, etc.) and indicators (e.g. DOZN tool and life cycle assessment, LCA, studies) applied to organic transformations such as synthesis of the amide bond, carbamates, heterocycles, active pharmaceutical ingredients (APIs), porphyrins, porous organic polymers (POPs), metal- or acid-catalysed processes, multicomponent and condensation reactions, rearrangements, etc. The generalized absence of bulk solvents, the precise control over the stoichiometry (i.e., using agents in a stoichiometrically rather than in excess), and the more selective reactions enabling simplified work-up procedures are the distinctive factors, marking the superiority of mechanochemical processes over solution-based chemistry.
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Affiliation(s)
| | - Jean-Noël Volle
- ICGM, Univ Montpellier, CNRS, ENSCM, 34293 Montpellier, France.
| | - Andrea Porcheddu
- Dipartimento di Scienze Chimiche e Geologiche, Università degli Studi di Cagliari, Cittadella Universitaria, 09042, Monserrato (CA), Italy
| | - David Virieux
- ICGM, Univ Montpellier, CNRS, ENSCM, 34293 Montpellier, France.
| | - Felipe García
- Departamento de Química Orgánica e Inorgánica, Facultad de Química, Universidad de Oviedo, Julián Claveria 8, Oviedo, 33006, Asturias, Spain.
- School of Chemistry, Monash University, Clayton, Victoria 3800, Australia.
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Pumice as a Novel Natural Heterogeneous Catalyst for the Designation of 3,4-Dihydropyrimidine-2-(1 H)-ones/thiones under Solvent-Free Conditions. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27186044. [PMID: 36144781 PMCID: PMC9503633 DOI: 10.3390/molecules27186044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 09/02/2022] [Accepted: 09/09/2022] [Indexed: 11/30/2022]
Abstract
In this study, pumice is used as a novel natural heterogeneous catalyst for the synthesis of 3,4-dihydropyrimidine-2-(1H)-ones/thiones via the one-pot multi-component condensation of aromatic aldehydes, urea/thiourea, and ethyl acetoacetate or acetylacetone in excellent yields (up to 98%). The physical and chemical properties of the catalyst were studied. Their geochemical analysis revealed a basaltic composition. Furthermore, X-ray diffraction showed that it is composed of amorphous materials with clinoptilolite and heulandites zeolite minerals in its pores. Moreover, pumice has a porosity range from 78.2–83.9% (by volume) and is characterized by a mesoporous structure (pore size range from 21.1 to 64.5 nm). Additionally, it has a pore volume between 0.00531 and 0.00781 m2/g and a surface area between 0.053 and 1.47 m2/g. The latter facilitated the reaction to proceed in a short time frame as well as in excellent yields. It is worth noting that our strategy tolerates the use of readily available, cheap, non-toxic, and thermally stable pumice catalyst. The reactions proceeded smoothly under solvent-free conditions, and products were isolated without tedious workup procedures in good yields and high purity. Indeed, pumice can be reused for at least five reuse cycles without affecting its activity.
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Patel PN, Talati KS, Deshmukh AG, Desai DH, Patel NC. Secondary Amine Catalysed Diastereoselective Cross Domino Reaction: Simple and Efficient Synthesis of Heteroaryl-Substituted Cyclohexanols. RUSS J GEN CHEM+ 2022. [DOI: 10.1134/s1070363222040107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Zheng J, Fan S, Liu S, Shen G, Si WD, Dong X, Huang X, Zhang Y, Yao Q, Li Z, Sun D. In situ ball-milling gram-scale preparation of polyoxoniobate-intercalated MgAl-layered double hydroxides for selective aldol and Michael addition cascade reactions. Inorg Chem Front 2022. [DOI: 10.1039/d2qi01167k] [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
A facile one-step ball-milling strategy to prepare gram-scale Mg3Al-LDH-Nb6 has been demonstrated and the thus-obtained catalyst exhibited efficient selective catalytic activities in the synthesis of biologically active organic molecules in water.
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Affiliation(s)
- Jun Zheng
- Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology, School of Chemistry & Chemical Engineering, Liaocheng University, Liaocheng, 252059, P. R. China
| | - Shuhua Fan
- Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology, School of Chemistry & Chemical Engineering, Liaocheng University, Liaocheng, 252059, P. R. China
| | - Sen Liu
- Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology, School of Chemistry & Chemical Engineering, Liaocheng University, Liaocheng, 252059, P. R. China
| | - Guodong Shen
- Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology, School of Chemistry & Chemical Engineering, Liaocheng University, Liaocheng, 252059, P. R. China
| | - Wei-Dan Si
- School of Chemistry and Chemical Engineering, State Key Laboratory of Crystal Materials, Shandong University, Ji'nan, 250100, People's Republic of China
| | - Xinyi Dong
- Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology, School of Chemistry & Chemical Engineering, Liaocheng University, Liaocheng, 252059, P. R. China
| | - Xianqiang Huang
- Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology, School of Chemistry & Chemical Engineering, Liaocheng University, Liaocheng, 252059, P. R. China
| | - Yalin Zhang
- Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology, School of Chemistry & Chemical Engineering, Liaocheng University, Liaocheng, 252059, P. R. China
| | - Qingxia Yao
- Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology, School of Chemistry & Chemical Engineering, Liaocheng University, Liaocheng, 252059, P. R. China
| | - Zhen Li
- Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology, School of Chemistry & Chemical Engineering, Liaocheng University, Liaocheng, 252059, P. R. China
| | - Di Sun
- School of Chemistry and Chemical Engineering, State Key Laboratory of Crystal Materials, Shandong University, Ji'nan, 250100, People's Republic of China
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5
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Yadav GD, Wagh DP. Claisen‐Schmidt Condensation using Green Catalytic Processes: A Critical Review. ChemistrySelect 2020. [DOI: 10.1002/slct.202001737] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Ganapati D. Yadav
- Department of Chemical EngineeringInstitute of Chemical Technology Nathalal Parekh Marg, Matunga Mumbai 400019 India
| | - Dipti P. Wagh
- Department of Chemical EngineeringInstitute of Chemical Technology Nathalal Parekh Marg, Matunga Mumbai 400019 India
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Gomes C, Vinagreiro CS, Damas L, Aquino G, Quaresma J, Chaves C, Pimenta J, Campos J, Pereira M, Pineiro M. Advanced Mechanochemistry Device for Sustainable Synthetic Processes. ACS OMEGA 2020; 5:10868-10877. [PMID: 32455207 PMCID: PMC7240818 DOI: 10.1021/acsomega.0c00521] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Accepted: 04/03/2020] [Indexed: 05/02/2023]
Abstract
Mechanochemistry is an alternative for sustainable solvent-free processes that has taken the big step to become, in the near future, a useful synthetic method for academia and the fine chemical industry. The apparatus available, based on ball milling systems possessing several optimizable variables, requires too many control and optimization experiments to ensure reproducibility, which has limited its widespread utilization so far. Herein, we describe the development of an automatic mechanochemical single-screw device consisting of an electrical motor, a drill, and a drill chamber. The applicability and versatility of the new device are demonstrated by the implementation of di- and multicomponent chemical reactions with high reproducibility, using mechanical action exclusively. As examples, chalcones, dihydropyrimidinones, dihydropyrimidinethiones, pyrazoline, and porphyrins, were synthesized with high yields. The unprecedented sustainability is demonstrated by comparison of EcoScale and E-factor values of these processes with those previously described in the literature.
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Affiliation(s)
- Carla Gomes
- University
of Coimbra, CQC, Department of Chemistry, Rua Larga, 3004-535 Coimbra, Portugal
| | - Carolina S. Vinagreiro
- University
of Coimbra, CQC, Department of Chemistry, Rua Larga, 3004-535 Coimbra, Portugal
| | - Liliana Damas
- University
of Coimbra, CQC, Department of Chemistry, Rua Larga, 3004-535 Coimbra, Portugal
| | - Gilberto Aquino
- Faculty
of Pharmacy, Exact Sciences and Technology Unit, State University of Goias, 75132400 Anapolis, Goias, Brazil
| | - Joana Quaresma
- LEDAP,
Departamento de Engenharia Mecânica, FCT-Universidade de Coimbra, Polo II, 3030-194 Coimbra, Portugal
| | - Cristina Chaves
- University
of Coimbra, CQC, Department of Chemistry, Rua Larga, 3004-535 Coimbra, Portugal
| | - João Pimenta
- LEDAP,
Departamento de Engenharia Mecânica, FCT-Universidade de Coimbra, Polo II, 3030-194 Coimbra, Portugal
| | - José Campos
- LEDAP,
Departamento de Engenharia Mecânica, FCT-Universidade de Coimbra, Polo II, 3030-194 Coimbra, Portugal
| | - Mariette Pereira
- University
of Coimbra, CQC, Department of Chemistry, Rua Larga, 3004-535 Coimbra, Portugal
- . Tel: +351919853716. Fax: +351239852080
| | - Marta Pineiro
- University
of Coimbra, CQC, Department of Chemistry, Rua Larga, 3004-535 Coimbra, Portugal
- . Tel: +351239854479. Fax: +351239852080
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Hematinezhad K, Nikpassand M, Fekri LZ. Grinding Synthesis of Pyrazolyl-Bis Coumarinyl Methanes Using Potassium 2-Oxoimidazolidine-1,3-diide. Curr Org Synth 2020; 16:303-308. [PMID: 31975680 DOI: 10.2174/1570179416666190101142542] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Revised: 11/30/2018] [Accepted: 12/03/2018] [Indexed: 11/22/2022]
Abstract
AIM AND OBJECTIVE Potassium 2-oxoimidazolidine-1,3-diide (POImD) as a novel and reusable catalyst was used for the synthesis of pyrazolyl-bis coumarinyl methanes by a nucleophilic addition reaction of synthetized pyrazolecarbaldehyde and two equivalents of 4-hydroxycoumarin under grinding. The catalyst can be reused and recovered several times without loss of activity. This method provides several advantages such as eco-friendliness, simple work-up and shorter reaction time as well as excellent yields. All of the synthesized compounds were characterized by IR, 1H and 13C NMR spectroscopy and elemental analyses. MATERIAL AND METHOD Synthetized pyrazole carbaldehyde 1a (1 mmol), 4-hydroxycoumarin 2 (2 mmol), 1 mmol of POImD and 10mL of H2O were ground in a mortar by a pestle for 30-90 minutes. After the completion of the reaction, as monitored by TLC on silica gel using ethyl acetate/n-hexane (1:2), the mixture was allowed to cool to room temperature. After completion of the reaction, we extracted the product with CH2Cl2/H2O. This was followed by separation of phases, evaporation of the organic phase and recrystallization of the residue with 50 mL of ethanol/H2O (1:1). The pure product was then obtained in 87 to 96% yield. The aqueous phase was concentrated under reduced pressure to recover the catalyst for subsequent use. RESULTS To continue our ongoing studies to synthesize heterocyclic and pharmaceutical compounds by mild, facile and efficient protocols, herein we wish to report our experimental results on the synthesis of pyrazolylbis coumarinyl methanes, using various synthetized pyrazole carbaldehydes and 4-hydroxycoumarin in the presence of POImD in aqueous media at room temperature. CONCLUSION Finally, we developed an efficient, fast and convenient procedure for the three-component synthesis of pyrazolyl-bis coumarinyl methanes through the reaction of pyrazole carbaldehydes and 4- hydroxycoumarin, using POImD as a novel and reusable catalyst. The remarkable advantage offered by this method is that the catalyst is non-toxic, inexpensive, easy to handle and reusable. A short reaction time, simple work-up procedure, high yields of product with better purity and the green aspect by avoiding a hazardous solvent and a toxic catalyst are the other advantages. To the best of our knowledge, this is the first report on the synthesis of pyrazolyl-bis coumarinylmethane derivatives using potassium 2-oxoimidazolidine-1,3-diide (POImD).
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Affiliation(s)
- Kazem Hematinezhad
- Department of Chemistry, Rasht Branch, Islamic Azad University, Rasht, Iran
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Rocco D, Housecroft CE, Constable EC. Synthesis of Terpyridines: Simple Reactions-What Could Possibly Go Wrong? Molecules 2019; 24:E1799. [PMID: 31075948 PMCID: PMC6539753 DOI: 10.3390/molecules24091799] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 05/07/2019] [Accepted: 05/08/2019] [Indexed: 11/25/2022] Open
Abstract
The preparation of 24-functionalized 12,22:26,32-terpyridines (4'-functionalized 3,2:6',3''-terpyridines) by the reaction of three 4-alkoxybenzaldehydes with 3-acetylpyridine and ammonia was investigated; under identical reaction conditions, two (R = nC4H9, C2H5) gave the expected products whereas a third (R = nC3H7) gave only a cyclohexanol derivative derived from the condensation of three molecules of 3-acetylpyridine with two of 4-(n-propoxy)benzaldehyde. A comprehensive survey of ''unexpected'' products from reactions of ArCOCH3 derivatives with aromatic aldehydes is presented. Three different types of alternative product are identified.
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Affiliation(s)
- Dalila Rocco
- University of Basel, Department of Chemistry, BPR 1096, Mattenstrasse 24a, CH-4058 Basel, Switzerland.
| | - Catherine E Housecroft
- University of Basel, Department of Chemistry, BPR 1096, Mattenstrasse 24a, CH-4058 Basel, Switzerland.
| | - Edwin C Constable
- University of Basel, Department of Chemistry, BPR 1096, Mattenstrasse 24a, CH-4058 Basel, Switzerland.
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Mahdi F, Sid A, Bouchene R, Mosset P, Roisnel T. ( E, E)-3-Methyl-2,5-bis-(4-methyl-benzyl-idene)cyclo-penta-none: synthesis, characterization, Hirshfeld surface analysis and anti-bacterial activity. Acta Crystallogr E Crystallogr Commun 2019; 75:506-511. [PMID: 31161065 PMCID: PMC6509686 DOI: 10.1107/s2056989019003827] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Accepted: 03/19/2019] [Indexed: 11/25/2022]
Abstract
The title compound, (E,E)-3-methyl-2,5-bis-(4-methyl-benzyl-idene)cyclo-penta-none (MBMCP), C22H22O, was obtained by Claisen-Schmidt condensation of 4-methyl-benzaldehyde with 3-methyl-cyclo-penta-none in good yield. The structure of MBMCP was studied using UV, FT-IR and Raman spectroscopy, single-crystal X-ray diffraction (XRD) measurements, and 1H and 13C nuclear magnetic resonance (NMR) spectroscopy. The mol-ecular structure of MBMCP is fully extended in the E,E configuration. C-H⋯π stacking inter-actions play a significant role in the stabilization of the mol-ecular packing. Hirshfeld surface analysis was used to qu-antify the non-covalent inter-actions in the crystal lattice. Microbiological studies were performed to investigate the anti-microbial activity of this new product.
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Affiliation(s)
- Fatiha Mahdi
- Laboratoire des Sciences Analytiques, Matériaux et Environnement (LSAME), Université Larbi Ben M’hidi, Oum El Bouaghi, 04000, Algeria
| | - Assia Sid
- Laboratoire des Sciences Analytiques, Matériaux et Environnement (LSAME), Université Larbi Ben M’hidi, Oum El Bouaghi, 04000, Algeria
| | - Rafika Bouchene
- Département Sciences de la Matière, Faculté des Sciences Exactes et Sciences de la Nature et de la Vie, Université Larbi Ben M’hidi, Oum El Bouaghi, 04000, Algeria
| | - Paul Mosset
- Université de Rennes 1, Institut des Sciences Chimiques de Rennes, CNRS UMR, 6226, Avenue du Général Leclerc, 35042 Rennes Cedex, France
| | - Thierry Roisnel
- Université de Rennes 1, Institut des Sciences Chimiques de Rennes, CNRS UMR, 6226, Avenue du Général Leclerc, 35042 Rennes Cedex, France
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Hu X, Guo J, Yin Z, Shan Z. First Experimental Evidence of Intramolecular Weak Bifurcated H Bond between Aliphatic C-H and Aromatic Cl Atoms: X-Ray Crystallographic Investigation on the syn
Head-to-Head Dimer of 2,6-Dichlorochalcone. ChemistrySelect 2018. [DOI: 10.1002/slct.201702945] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Xiaoyun Hu
- College of Chemistry and Materials; South-Central University for Nationalities; Wuhan, Hubei Province China
| | - Jianxin Guo
- College of Chemistry and Materials; South-Central University for Nationalities; Wuhan, Hubei Province China
| | - Zhongyou Yin
- College of Chemistry and Materials; South-Central University for Nationalities; Wuhan, Hubei Province China
| | - Zixing Shan
- College of Chemistry and Molecular Sciences; Wuhan University; Wuhan, Hubei Province China
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Patel PN, Chadha A. A simple metal free highly diastereoselective synthesis of heteroaryl substituted (±) cyclohexanols by a branched domino reaction. Tetrahedron 2018. [DOI: 10.1016/j.tet.2017.11.070] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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El-Hashash MAEA, Gomha SM, El-Arab EE. Utility of Pyrazolylchalcone Synthon to Synthesize Azolopyrimidines under Grindstone Technology. Chem Pharm Bull (Tokyo) 2017; 65:90-96. [PMID: 28049919 DOI: 10.1248/cpb.c16-00759] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A series of pyrazolyl-triazolo[1,5-a]pyrimidines, pyrazolyl-tetrazolo[1,5-a]pyrimidines, pyrazolyl-benzo[4,5]imidazo[1,2-a]pyrimidines and bis-azolopyrimidines were prepared by reaction of pyrazolyl-chalcones or its bis-pyrazolyl-chalcones with the appropriate heterocyclic amines as aminotriazole, aminotetrazole, 2-aminobenzimidazole and 4,6-dimethyl-1H-pyrazolo[3,4-b]pyridin-3-amine by grinding method. The newly synthesized compounds have been characterized on the basis of elemental analysis and spectral data (IR, 1H- and 13C-NMR, Mass). Moreover, the newly synthesized products were screened for their in vitro antibacterial activities and the results showed that compounds 5f and 11d exhibited excellent activities compared with penicillin G and streptomycin as reference drugs.
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GOMHA S, ABDALLAH M, ABD EL-AZIZ M, SERAG N. Ecofriendly one-pot synthesis and antiviral evaluation of novel pyrazolyl pyrazolines of medicinal interest. Turk J Chem 2016; 40:484-498. [DOI: 10.3906/kim-1510-25] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/02/2023] Open
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Zhang J, Xu J. Chemoselectivity in the Reaction of 2-Diazo-3-oxo-3-phenylpropanal with Aldehydes and Ketones. Helv Chim Acta 2013. [DOI: 10.1002/hlca.201200532] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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A facile solvent free Claisen-Schmidt reaction: synthesis of α,α'-bis-(substituted-benzylidene)cycloalkanones and α,α'-bis-(substituted-alkylidene)cycloalkanones. Molecules 2012; 17:571-83. [PMID: 22231494 PMCID: PMC6269007 DOI: 10.3390/molecules17010571] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2011] [Revised: 12/30/2011] [Accepted: 01/04/2012] [Indexed: 11/16/2022] Open
Abstract
Solvent-free Claisen-Schmidt reactions of cycloalkanones with various substituted benzaldehydes (aryl aldehydes) using solid NaOH (20 mol%) and applying a grinding technique were studied. Quantitative yields (96-98%) of α,α'-bis-(substituted-benzylidene)cycloalkanones were obtained. Aliphatic aldehydes also provided α,α'-bis-(substituted-alkylidene)cycloalkanones in very good yields with minor amounts of a-(substituted-alkylidene)cycloalkanones. The catalytic performance of solid NaOH was examined. The molar ratio of NaOH was optimized. The catalytic effect of solid NaOH was also evaluated by comparing it with KOH, NaOAc, and NH(4)OAc and it turns out that 20 mol% of solid NaOH was good enough to catalyze the Claisen-Schmidt reactions of cycloalkanones with various substituted benzaldehydes. Additionally, the regioselectivity of the Claisen-Schmidt reaction of acetone with benzaldehyde was examined. Using the same method, we could synthesize the corresponding bis-benzylidene- and mono-benzylideneacetone separately in 98% and 96% yields, respectively.
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