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Vicente AI, Coelho JAS, Simeonov SP, Lazarova HI, Popova MD, Afonso CAM. Oxidation of 5-Chloromethylfurfural (CMF) to 2,5-Diformylfuran (DFF). Molecules 2017; 22:E329. [PMID: 28230746 PMCID: PMC6155580 DOI: 10.3390/molecules22020329] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2017] [Revised: 02/10/2017] [Accepted: 02/14/2017] [Indexed: 11/16/2022] Open
Abstract
2,5-Diformylfuran (DFF) is an important biorenewable building block, namely for the manufacture of new polymers that may replace existing materials derived from limited fossil fuel resources. The current reported methods for the preparation of DFF are mainly derived from the oxidation of 5-hydroxymethylfurfural (HMF) and, to a lesser extent, directly from fructose. 5-Chloromethylfurfural (CMF) has been considered an alternative to HMF as an intermediate building block due to its advantages regarding stability, polarity, and availability from glucose and cellulose. The only reported method for the transformation of CMF to DFF is restricted to the use of DMSO as the solvent and oxidant. We envisioned that the transformation could be performed using more attractive conditions. To that end, we explored the oxidation of CMF to DFF by screening several oxidants such as H₂O₂, oxone, and pyridine N-oxide (PNO); different heating methods, namely thermal and microwave irradiation (MWI); and also flow conditions. The combination of PNO (4 equiv.) and Cu(OTf)₂ (0.5 equiv.) in acetonitrile was identified as the best system, which lead to the formation of DFF in 54% yield under MWI for 5 min at 160 °C. Consequently, a range of different heterogeneous copper catalysts were tested, which allowed for catalyst reuse. Similar results were also observed under flow conditions using copper immobilized on silica under thermal heating at 160 °C for a residence time of 2.7 min. Finally, HMF and 5,5'-oxybis(5-methylene-2-furaldehyde) (OBMF) were the only byproducts identified under the reaction conditions studied.
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Rocha Â, Teixeira R, Lourenço NMT, Afonso CAM. Enzymatic Kinetic Resolution of Secondary Alcohols Using an Ionic Anhydride Generated In Situ. CHEMSUSCHEM 2017; 10:296-302. [PMID: 27709801 DOI: 10.1002/cssc.201600579] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2016] [Revised: 06/18/2016] [Indexed: 06/06/2023]
Abstract
We developed a method for the resolution of secondary alcohols using an ionic anhydride acylating agent prepared directly in the reaction medium containing the biocatalyst Candida antarctica lipase B (CALB). NMR studies showed that mixing all components at the same time does not interfere with the coupling reaction or the enzymatic activity. After optimization of the reaction conditions, the method allowed the resolution of a number of substrates in very high conversions (46-48 %) and enantiomeric ratios (E>170) along with an easy recovery of both enantiomers without the need for preparative chromatographic separation. Additionally, both the starting ionic acid and the biocatalyst could be recovered and reused up to nine cycles without significant loss of enantioselectivity.
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Ravasco JMJM, Coelho JAS, Simeonov SP, Afonso CAM. Bifunctional Cr3+ modified ion exchange resins as efficient reusable catalysts for the production and isolation of 5-hydroxymethylfurfural from glucose. RSC Adv 2017. [DOI: 10.1039/c6ra22539j] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Cr3+ modified readily available cation exchange resins were prepared and explored as heterogeneous bifunctional catalysts for dehydration of glucose to 5-hydroxymethylfurfural (HMF) in tetraethyl ammonium bromide (TEAB)/water as reaction medium.
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Restolho J, Barroso M, Saramago B, Dias M, Afonso CAM. Response to the letter to the editor Reply to Restolho et al. "Contactless decontamination of hair samples: cannabinoids" by Moosmann and Auwärter. Drug Test Anal 2016; 9:290-292. [PMID: 28035756 DOI: 10.1002/dta.2150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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55
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Siopa F, Figueiredo T, Frade RFM, Neto I, Meirinhos A, Reis CP, Sobral RG, Afonso CAM, Rijo P. Choline-Based Ionic Liquids: Improvement of Antimicrobial Activity. ChemistrySelect 2016. [DOI: 10.1002/slct.201600864] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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56
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Assoah B, Veiros LF, Afonso CAM, Candeias NR. Biomass-Based and Oxidant-Free Preparation of Hydroquinone from Quinic Acid. European J Org Chem 2016. [DOI: 10.1002/ejoc.201600616] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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57
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Simeonov SP, Nunes JPM, Guerra K, Kurteva VB, Afonso CAM. Synthesis of Chiral Cyclopentenones. Chem Rev 2016; 116:5744-893. [DOI: 10.1021/cr500504w] [Citation(s) in RCA: 159] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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58
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Ladeiras D, M. Monteiro C, Pereira F, P. Reis C, A. M. Afonso C, Rijo P. Reactivity of Diterpenoid Quinones: Royleanones. Curr Pharm Des 2016; 22:1682-714. [DOI: 10.2174/1381612822666151211094521] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Accepted: 12/10/2015] [Indexed: 11/22/2022]
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59
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Vale JR, Siopa F, Branco PS, Afonso CAM. Ring Opening of 6-Azabicyclo[3.1.0]hex-3-en-2-ols in Water under Mild Conditions. European J Org Chem 2016. [DOI: 10.1002/ejoc.201501468] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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60
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Abstract
Some decomposition occurs below 100 °C for urea based deep eutectic mixtures/solvents (DES) liberating ammonia and is enhanced for diols by formation of carbonates.
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Rosatella AA, Siopa F, Frade RFM, Afonso CAM. New low viscous cholinium-based magnetic ionic liquids. NEW J CHEM 2016. [DOI: 10.1039/c5nj03165f] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This study describes the synthesis of cholinium-based magnetic ionic liquids that are liquid at room temperature and have low toxicity to human cells.
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62
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Sowmiah S, Veiros LF, Esperança JMSS, Rebelo LP, Afonso CAM. Organocatalyzed One-Step Synthesis of Functionalized N-Alkyl-Pyridinium Salts from Biomass Derived 5-Hydroxymethylfurfural. Org Lett 2015; 17:5244-7. [DOI: 10.1021/acs.orglett.5b02573] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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63
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Gomes RFA, Coelho JAS, Frade RFM, Trindade AF, Afonso CAM. Synthesis of Symmetric Bis(N-alkylaniline)triarylmethanes via Friedel–Crafts-Catalyzed Reaction between Secondary Anilines and Aldehydes. J Org Chem 2015; 80:10404-11. [DOI: 10.1021/acs.joc.5b01875] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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64
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Rodrigues CAB, Frade RFM, Albuquerque IS, Perry MJ, Gut J, Machado M, Rosenthal PJ, Prudêncio M, Afonso CAM, Moreira R. Targeting the Erythrocytic and Liver Stages of Malaria Parasites withs-Triazine-Based Hybrids. ChemMedChem 2015; 10:883-90. [DOI: 10.1002/cmdc.201500011] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Revised: 02/15/2015] [Indexed: 11/08/2022]
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Gomes LFR, Veiros LF, Maulide N, Afonso CAM. Back Cover: Diazo- and Transition-Metal-Free CH Insertion: A Direct Synthesis of β-Lactams (Chem. Eur. J. 4/2015). Chemistry 2015. [DOI: 10.1002/chem.201590014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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66
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Restolho J, Barroso M, Dias M, Afonso CAM, Saramago B. Capture of Opiates by Ionic Liquids. J SOLUTION CHEM 2014. [DOI: 10.1007/s10953-014-0272-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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67
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Gomes LFR, Veiros LF, Maulide N, Afonso CAM. Diazo- and Transition-Metal-Free CH Insertion: A Direct Synthesis of β-Lactams. Chemistry 2014; 21:1449-53. [DOI: 10.1002/chem.201404990] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2014] [Indexed: 11/06/2022]
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68
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E Silva FA, Siopa F, Figueiredo BFHT, Gonçalves AMM, Pereira JL, Gonçalves F, Coutinho JAP, Afonso CAM, Ventura SPM. Sustainable design for environment-friendly mono and dicationic cholinium-based ionic liquids. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2014; 108:302-310. [PMID: 25108510 DOI: 10.1016/j.ecoenv.2014.07.003] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Revised: 06/27/2014] [Accepted: 07/03/2014] [Indexed: 06/03/2023]
Abstract
Cholinium-based ionic liquids are receiving crescent interest in diverse areas of application given their biological compatibility and potential for industrial application. In this work, mono and dicationic cholinium ionic liquids as well as cholinium derivatives were synthesized and their toxicity assessed using the luminescent bacteria Vibrio fischeri. A range of cholinium derivatives was synthesized, using different amines and the correspondent brominated derivatives, through the alkylation of the amine with the halide in MeCN. The results indicate that their toxicity is highly dependent on the structural modifications of the cholinium cation, mainly related to the alkyl side or linkage chain length, number of hydroxyethyl groups and insertion of carbon-carbon multiple bonds. The data indicated that it is possible to perform environmentally advantageous structural alterations, namely the addition of double bonds, which would not negatively affect V. fischeri. Moreover, the dicationic compounds revealed a significantly lower toxicity than the monocationic counterparts. The picture emerging from the results supports the idea that cholinium derivatives are promising ionic liquids with a low environmental impact, emphasizing the importance of a careful and directed design of ionic liquid structures.
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69
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Monteiro CM, Lourenço NMT, Ferreira FC, Afonso CAM. PEG
600
‐Carboxylates as Efficient Reusable Reaction Media and Acylating Agents for the Resolution of
sec‐
Alcohols. Chempluschem 2014. [DOI: 10.1002/cplu.201402049] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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70
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Scovazzo P, Portugal CAM, Rosatella AA, Afonso CAM, Crespo JG. Hydraulic pressures generated in magnetic ionic liquids by paramagnetic fluid/air interfaces inside of uniform tangential magnetic fields. J Colloid Interface Sci 2014; 428:16-23. [PMID: 24910029 DOI: 10.1016/j.jcis.2014.04.023] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Revised: 04/09/2014] [Accepted: 04/12/2014] [Indexed: 11/26/2022]
Abstract
HYPOTHESIS Magnetic Ionic Liquid (MILs), novel magnetic molecules that form "pure magnetic liquids," will follow the Ferrohydrodynamic Bernoulli Relationship. Based on recent literature, the modeling of this fluid system is an open issue and potentially controversial. EXPERIMENTS We imposed uniform magnetic fields parallel to MIL/air interfaces where the capillary forces were negligible, the Quincke Problem. The size and location of the bulk fluid as well as the size and location of the fluid/air interface inside of the magnetic field were varied. MIL properties varied included the density, magnetic susceptibility, chemical structure, and magnetic element. FINDINGS Uniform tangential magnetic fields pulled the MILs up counter to gravity. The forces per area were not a function of the volume, the surface area inside of the magnetic field, or the volume displacement. However, the presence of fluid/air interfaces was necessary for the phenomena. The Ferrohydrodynamic Bernoulli Relationship predicted the phenomena with the forces being directly related to the fluid's volumetric magnetic susceptibility and the square of the magnetic field strength. [emim][FeCl4] generated the greatest hydraulic head (64-mm or 910 Pa at 1.627 Tesla). This work could aid in experimental design, when free surfaces are involved, and in the development of MIL applications.
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71
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Trindade AF, Frade RFM, Maçôas EMS, Graça C, Rodrigues CAB, Martinho JMG, Afonso CAM. "Click and go": simple and fast folic acid conjugation. Org Biomol Chem 2014; 12:3181-90. [PMID: 24723199 DOI: 10.1039/c4ob00150h] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Folic acid targeting by functionalization of the terminal γ-carboxylic acid is one of the most important strategies to selectively deliver chemotherapeutics and dyes to cancer cells which overexpress folate receptors. However, conjugation of folic acid is limited by its unique solubility and by selectivity issues imposing the need for expensive preparative reverse-phase chromatographic purification to isolate γ-folate conjugates. Herein is provided a novel synthetic tool for the synthesis of new folic acid conjugates with excellent γ-purity based on strain-promoted alkyne-azide cycloadditions with a γ-folate-cyclooctyne conjugate 3. To demonstrate the potential of this methodology several new folate conjugates were synthesized with high γ-purity and without using any type of chromatographic purification by reacting conjugate 3 with several fluorescent probes, polymers and siliceous materials bearing azide. In addition, the cycloaddition reaction between conjugate 3 and an azido-derived fluorescent dye was successfully performed in cellular media leading to an increase of fluorescence in the cells which overexpress folate receptors (NCI-H460).
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72
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Coelho JAS, Trindade AF, André V, Teresa Duarte M, Veiros LF, Afonso CAM. Trienamines derived from 5-substituted furfurals: remote ε-functionalization of 2,4-dienals. Org Biomol Chem 2014; 12:9324-8. [DOI: 10.1039/c4ob01759e] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The remote selective ε-functionalization of 5-substituted furfurals by trienamine catalysis is described, resulting in a new scaffold.
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73
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António JPM, Frade RFM, Santos FMF, Coelho JAS, Afonso CAM, Gois PMP, Trindade AF. NHC catalysed direct addition of HMF to diazo compounds: synthesis of acyl hydrazones with antitumor activity. RSC Adv 2014. [DOI: 10.1039/c4ra03710c] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Synthesis and evaluation of HMF derived N-acyl hydrazone with antitumor activity.
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74
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Ferreira JP, Viveiros R, Lourenço A, Soares da Silva M, Rosatella A, Casimiro T, Afonso CAM. Integrated desulfurization of diesel by combination of metal-free oxidation and product removal by molecularly imprinted polymers. RSC Adv 2014. [DOI: 10.1039/c4ra11666f] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The desulfurization of diesel containing dibenzothiophene (DBT) is achieved based on the combination of Brønsted acid catalyzed oxidation of DBT by H2O2 and the selective removal of the oxidized products using a molecularly imprinted polymer (MIP) produced in supercritical carbon dioxide.
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75
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Rodrigues CAB, Graça C, Maçôas E, Fedorov A, Afonso CAM, Martinho JMG. Excited-State Proton Transfer of Fluorescein Anion as an Ionic Liquid Component. J Phys Chem B 2013; 117:14108-14. [DOI: 10.1021/jp408616r] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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76
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Simeonov SP, Coelho JAS, Afonso CAM. Integrated chemo-enzymatic production of 5-hydroxymethylfurfural from glucose. CHEMSUSCHEM 2013; 6:997-1000. [PMID: 23606522 DOI: 10.1002/cssc.201300176] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2013] [Indexed: 06/02/2023]
Abstract
Sweets for my sweet: The production and isolation of 5-hydroxymethylfurfural (HMF) in high yield and purity is demonstrated by using a combination of glucose-fructose isomerization with sweetzyme in wet tetraethylammonium bromide (TEAB) and clean fructose dehydration to HMF catalyzed by using HNO₃ under moderate conditions, which allow the reuse of any unreacted glucose and TEAB.
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77
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Frade RFM, Simeonov S, Rosatella AA, Siopa F, Afonso CAM. Toxicological evaluation of magnetic ionic liquids in human cell lines. CHEMOSPHERE 2013; 92:100-105. [PMID: 23561571 DOI: 10.1016/j.chemosphere.2013.02.047] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2012] [Revised: 02/07/2013] [Accepted: 02/17/2013] [Indexed: 06/02/2023]
Abstract
Magnetic ionic liquids (MILs) are new solvents with an interesting broad of applications however their toxicity is still an open issue. In this paper we report the toxicity of [C(8)MIM] and [Choline-C(n)] based magnetic ionic liquids assessed in two human cell lines: normal skin fibroblasts (CRL-1502) and colorectal adenocarcinoma cells (CaCo-2), acquiring this last characteristics of human enterocytes after differentiation. The results showed that [CoCl(4)] and [MnCl(4)] are more prone to generate cytotoxicity.
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78
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P. Guerra K, A. M. Afonso C. Synthetic Survey and Activity of 2'-deoxy-methanocarba Nucleosides. Curr Org Synth 2013. [DOI: 10.2174/1570179411310020002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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79
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Coelho JAS, Trindade AF, Wanke R, Rocha BGM, Veiros LF, Gois PMP, Pombeiro AJL, Afonso CAM. N-Heterocyclic Carbene Dirhodium(II) Complexes as Catalysts for Allylic and Benzylic Oxidations. European J Org Chem 2013. [DOI: 10.1002/ejoc.201201300] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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80
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de Pedro I, García-Saiz A, González J, Ruiz de Larramendi I, Rojo T, Afonso CAM, Simeonov SP, Waerenborgh JC, Blanco JA, Ramajo B, Fernández JR. Magnetic ionic plastic crystal: choline[FeCl4]. Phys Chem Chem Phys 2013; 15:12724-33. [DOI: 10.1039/c3cp50749a] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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81
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Nunes JPM, Afonso CAM, Caddick S. Synthesis of 2,4-bifunctionalised cyclopentenones from 2-furaldehyde. RSC Adv 2013. [DOI: 10.1039/c3ra42663g] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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82
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Candeias NR, Carias C, Gomes LFR, André V, Duarte MT, Gois PMP, Afonso CAM. Asymmetric Intramolecular CH Insertion of α-Diazoacetamides in Water by Dirhodium(II) Catalysts Derived from Natural Amino Acids. Adv Synth Catal 2012. [DOI: 10.1002/adsc.201200101] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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83
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Simeonov SP, Coelho JAS, Afonso CAM. An integrated approach for the production and isolation of 5-hydroxymethylfurfural from carbohydrates. CHEMSUSCHEM 2012; 5:1388-1391. [PMID: 22740298 DOI: 10.1002/cssc.201200236] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2012] [Indexed: 06/01/2023]
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84
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Trindade AF, Coelho JAS, Afonso CAM, Veiros LF, Gois PMP. Fine Tuning of Dirhodium(II) Complexes: Exploring the Axial Modification. ACS Catal 2012. [DOI: 10.1021/cs200597a] [Citation(s) in RCA: 88] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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85
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Ventura SPM, Marques CS, Rosatella AA, Afonso CAM, Gonçalves F, Coutinho JAP. Toxicity assessment of various ionic liquid families towards Vibrio fischeri marine bacteria. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2012; 76:162-8. [PMID: 22019310 DOI: 10.1016/j.ecoenv.2011.10.006] [Citation(s) in RCA: 118] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2011] [Revised: 10/03/2011] [Accepted: 10/06/2011] [Indexed: 05/20/2023]
Abstract
The increasing interest on the application of ionic liquids (ILs) to a wide range of processes and products has been hampered by a lack of toxicological data, mainly in what concerns novel cations, such as guanidinium, phosphonium, and functionalized and non-functionalized imidazolium-based ILs. The present study reports the toxicity of five guanidinium-, six phosphonium, and six imidazolium-based ILs, towards the luminescent marine bacteria Vibrio fischeri. These new results clearly show that guanidinium-, unlike the imidazolium- and phosphonium-based ILs, do not follow the trend of increasing toxicity with the increase in the alkyl chain length. Moreover, the introduction of oxygenated groups on the alkyl chains, such as ether and ester, leads to a decrease of the toxicity of guanidinium and also imidazolium compounds. In what respects the effect of the different cations, it is possible to recognize that the phosphonium-based ILs seem to be more toxic when compared to the analog imidazolium-based ILs (with the same anion and alkyl chains).
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Kulkarni PS, Neves LA, Coelhoso IM, Afonso CAM, Crespo JG. Supported ionic liquid membranes for removal of dioxins from high-temperature vapor streams. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2012; 46:462-468. [PMID: 22087544 DOI: 10.1021/es2024302] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Dioxins and dioxin-like chemicals are predominantly produced by thermal processes such as incineration and combustion at concentrations in the range of 10-100 ng of I-TEQ/kg (I-TEQ = international toxic equivalents). In this work, a new approach for the removal of dioxins from high-temperature vapor streams using facilitated supported ionic liquid membranes (SILMs) is proposed. The use of ceramic membranes containing specific ionic liquids, with extremely low volatility, for dioxin removal from incineration sources is proposed owing to their stability at very high temperatures. Supported liquid membranes were prepared by successfully immobilizing the ionic liquids tri-C(8)-C(10)-alkylmethylammonium dicyanamide ([Aliquat][DCA]) and 1-n-octyl-3-methylimidazolium dicyanamide ([Omim][DCA]) inside the porous structure of ceramic membranes. The porous inorganic membranes tested were made of titanium oxide (TiO(2)), with a nominal pore size of 30 nm, and aluminum oxide (Al(2)O(3)), with a nominal pore size of 100 nm. The ionic liquids were characterized, and the membrane performance was assessed for the removal of dioxins. Different materials (membrane pore size, type of ionic liquid, and dioxin) and different operating conditions (temperature and flow rate) were tested to evaluate the efficiency of SILMs for dioxin removal. All membranes prepared were stable at temperatures up to 200 °C. Experiments with model incineration gas were also carried out, and the results obtained validate the potential of using ceramic membranes with immobilized ionic liquids for the removal of dioxins from high-temperature vapor sources.
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87
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Candeias NR, Afonso CAM, Gois PMP. Making expensive dirhodium(ii) catalysts cheaper: Rh(ii) recycling methods. Org Biomol Chem 2012; 10:3357-78. [DOI: 10.1039/c2ob06731e] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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88
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Piçarra S, Afonso CAM, Kurteva VB, Fedorov A, Martinho JMG, Farinha JPS. The influence of nanoparticle architecture on latex film formation and healing properties. J Colloid Interface Sci 2011; 368:21-33. [PMID: 22153277 DOI: 10.1016/j.jcis.2011.10.077] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2011] [Revised: 10/27/2011] [Accepted: 10/30/2011] [Indexed: 10/15/2022]
Abstract
We present a study of chain interdiffusion in films formed by specially architectured PBMA nanoparticles by Förster Resonance Energy Transfer -FRET. Polymer nanoparticles contained linear chains with narrower molecular weight distributions than other previous reports, allowing a more detailed study. Apparent fractions of mixing and diffusion coefficients, determined from the quantum efficiency of energy transfer, were used to characterize the interdiffusion mechanism in the different films. The resistance of the films to dissolution by a good solvent was finally correlated with the interdiffusion results, in order to get information about film healing. We concluded that whenever interdiffusion occurs between nanoparticles containing linear chains and fully cross-linked nanoparticles, healing becomes more effective in spite of showing slower interdiffusion. We also observed that particles with longer chains are more effective for film healing. Finally, we concluded that interdiffusion occurs both ways across interfaces in blends formed by particles swollen with linear chains of different molecular weights.
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Rosatella AA, Afonso CAM. Brønsted Acid-Catalyzed Dihydroxylation of Olefins in Aqueous Medium. Adv Synth Catal 2011. [DOI: 10.1002/adsc.201100187] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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90
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Branco LC, Serbanovic A, N. da Ponte M, Afonso CAM. Chiral Guanidinium Ionic Liquids for Asymmetric Dihydroxylation of Olefins with Recycling of the Catalytic System by Supercritical CO2. ACS Catal 2011. [DOI: 10.1021/cs2001626] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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91
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Frija LMT, Frade RFM, Afonso CAM. Isolation, chemical, and biotransformation routes of labdane-type diterpenes. Chem Rev 2011; 111:4418-52. [PMID: 21618966 DOI: 10.1021/cr100258k] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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92
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Guerra KP, Afonso CAM. Efficient Tandem Morita-Baylis-Hillman/Double Cross-Aldol Reaction between Cyclic Enones and Formaldehyde Promoted by N-Methylpyrrolidine. European J Org Chem 2011. [DOI: 10.1002/ejoc.201001612] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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93
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Frade RFM, Afonso CAM. Corrigendum to impact of ionic liquids in environment and humans: An overview. Hum Exp Toxicol 2010. [DOI: 10.1177/09603271100290121201] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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94
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Lourenço NMT, Monteiro CM, Afonso CAM. Ionic Acylating Agents for the Enzymatic Resolution of sec-Alcohols in Ionic Liquids. European J Org Chem 2010. [DOI: 10.1002/ejoc.201000640] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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95
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Kurteva VB, Afonso CAM. Synthesis of Cyclopentitols by Ring-Closing Approaches. Chem Rev 2009; 109:6809-57. [DOI: 10.1021/cr900169j] [Citation(s) in RCA: 100] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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96
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Candeias NR, Branco LC, Gois PMP, Afonso CAM, Trindade AF. More Sustainable Approaches for the Synthesis of N-Based Heterocycles. Chem Rev 2009; 109:2703-802. [DOI: 10.1021/cr800462w] [Citation(s) in RCA: 292] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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97
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Candeias NR, Veiros LF, Afonso CAM, Gois PMP. Water: A Suitable Medium for the Petasis Borono-Mannich Reaction. European J Org Chem 2009. [DOI: 10.1002/ejoc.200900056] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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98
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99
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Beija M, Afonso CAM, Martinho JMG. Synthesis and applications of Rhodamine derivatives as fluorescent probes. Chem Soc Rev 2009; 38:2410-33. [DOI: 10.1039/b901612k] [Citation(s) in RCA: 1095] [Impact Index Per Article: 73.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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100
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André V, Duarte MT, Trindade AF, Góis PMP, Afonso CAM. Tetra-μ-acetato-bis{[1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene]rhodium(II)}(Rh—Rh) tetrahydrofuran tetrasolvate. Acta Crystallogr C 2008; 64:m345-8. [DOI: 10.1107/s0108270108026589] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2008] [Accepted: 08/18/2008] [Indexed: 11/10/2022] Open
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