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García C, Bernardes CES, Piedade MF, Fumagalli G, Colombo E, Díaz-Lanza AM, Reis CP, Correia I, Ascensão L, Passarella D, da Piedade MEM, Rijo P. Dehydroroyleanone as a Building Block for a Drug Delivery Platform Based on Self-Assembled Nanoparticles: Structural Studies and Chemical Modification. ACS Omega 2022; 7:44180-44186. [PMID: 36506152 PMCID: PMC9730763 DOI: 10.1021/acsomega.2c05353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Accepted: 11/09/2022] [Indexed: 06/17/2023]
Abstract
6,7-Dehydroroyleanone (DHR) is a caspase-induced cytotoxic abietane diterpene, frequently found on Plectranthus spp. A pharmaceutical formulation consisting of a DHR-squalene conjugate was synthesized and analyzed by different techniques such as scanning electron microscopy (SEM). The facile production of the dispersion of DHR-squalene conjugate nanoparticles in phosphate buffer (pH 7.4) suggests that this nanodelivery platform may be an effective system to improve the solubility and bioavailability of DHR, so that therapeutical systemic levels may be achieved.
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Affiliation(s)
- Catarina García
- CBIOS—Universidade
Lusófona’s Research Center for Biosciences & Health
Technologies, 1749-024Lisboa, Portugal
- Departamento
de Ciencias Biomédicas (Área de Farmacología;
Nuevos A̅gentes Antitumorales, Acción Tóxica Sobre
Células Leucémicas, Facultad de Farmacia, Universidad de Alcalá de Henares, Ctra. Madrid-Barcelona km. 33,600, 28805Alcalá de Henares, Madrid, España
| | - Carlos E. S. Bernardes
- Centro
de Química Estrutural, Institute of Molecular Sciences, Departamento
de Química e Bioquímica, Faculdade
de Ciências, Universidade de Lisboa, 1749-016Lisboa, Portugal
| | - M. Fátima
M. Piedade
- Centro
de Química Estrutural, Institute of Molecular Sciences, Departamento
de Química e Bioquímica, Faculdade
de Ciências, Universidade de Lisboa, 1749-016Lisboa, Portugal
- Centro
de Química Estrutural, Institute of Molecular Sciences, Instituto
Superior Técnico, Universidade de
Lisboa, 1049-001Lisboa, Portugal
| | - Gaia Fumagalli
- Dipartimento
di Chimica, Università Degli Studi
di Milano, Via Golgi 19, 20133Milano, Italy
| | - Eleonora Colombo
- Dipartimento
di Chimica, Università Degli Studi
di Milano, Via Golgi 19, 20133Milano, Italy
| | - Ana M. Díaz-Lanza
- Departamento
de Ciencias Biomédicas (Área de Farmacología;
Nuevos A̅gentes Antitumorales, Acción Tóxica Sobre
Células Leucémicas, Facultad de Farmacia, Universidad de Alcalá de Henares, Ctra. Madrid-Barcelona km. 33,600, 28805Alcalá de Henares, Madrid, España
| | - Catarina P. Reis
- Instituto
de Investigação do Medicamento (iMed.ULisboa), Faculdade
de Farmácia, Universidade de Lisboa, 1649-003Lisboa, Portugal
- Instituto
de Biofísica e Engenharia Biomédica, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016Lisboa, Portugal
| | - Isabel Correia
- Centro
de Química Estrutural, Institute of Molecular Sciences, Instituto
Superior Técnico, Universidade de
Lisboa, 1049-001Lisboa, Portugal
| | - Lia Ascensão
- Centro
de Estudos do Ambiente e do Mar (CESAM), Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016Lisbon, Portugal
| | - Daniele Passarella
- Dipartimento
di Chimica, Università Degli Studi
di Milano, Via Golgi 19, 20133Milano, Italy
| | - Manuel E. Minas da Piedade
- Centro
de Química Estrutural, Institute of Molecular Sciences, Departamento
de Química e Bioquímica, Faculdade
de Ciências, Universidade de Lisboa, 1749-016Lisboa, Portugal
| | - Patrícia Rijo
- CBIOS—Universidade
Lusófona’s Research Center for Biosciences & Health
Technologies, 1749-024Lisboa, Portugal
- Instituto
de Investigação do Medicamento (iMed.ULisboa), Faculdade
de Farmácia, Universidade de Lisboa, 1649-003Lisboa, Portugal
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Feliciano IO, Silva DP, Piedade MFM, Bernardes CES, Minas da Piedade ME. First and Second Dissociation Enthalpies in Bi-Component Crystals Consisting of Maleic Acid and L-Phenylalanine. Molecules 2021; 26:molecules26185714. [PMID: 34577186 PMCID: PMC8469174 DOI: 10.3390/molecules26185714] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2021] [Revised: 09/09/2021] [Accepted: 09/14/2021] [Indexed: 11/16/2022] Open
Abstract
The energetics of the stepwise dissociation of a A:B2 bi-component crystal, according to A:B2(cr) → A:B(cr) + B(cr) and A:B(cr) → A(cr) + B(cr), was investigated using MA:Phe2 and MA:Phe (MA = maleic acid; Phe = L-phenylalanine) as model systems. The enthalpy changes associated with these sequential processes and with the overall dissociation reaction A:B2(cr) → A(cr) + 2B(cr) were determined by solution calorimetry. It was found that they are all positive, indicating that there is a lattice enthalpy gain when MA:Phe2 is formed, either from the individual precursors or by adding Phe to MA:Phe. Single-crystal X-ray diffraction (SCXRD) analysis showed that MA:Phe2 is best described as a protic salt containing a maleate anion (MA−) and two non-equivalent L-phenylalanine units, both linked to MA− by NH···O hydrogen bonds (H-bond): one of these units is protonated (HPhe+) and the other zwitterionic (Phe±). Only MA− and HPhe+ molecules are present in the MA:Phe lattice. In this case, however, NH···O and OH···O H-bonds are formed between each MA− unit and two HPhe+ molecules. Despite these structural differences, the enthalpy cost for the removal of the zwitterionic Phe± unit from the MA:Phe2 lattice to yield MA:Phe is only 0.9 ± 0.4 kJ mol−1 higher than that for the dissociation of MA:Phe, which requires a proton transfer from HPhe+ to MA− and the rearrangement of L-phenylalanine to the zwitterionic, Phe±, form. Finally, a comparison of the dissociation energetics and structures of MA:Phe and of the previously reported glycine maleate (MA:Gly) analogue indicated that parameters, such as the packing coefficient, density, hydrogen bonds formed, or fusion temperature, are not necessarily good descriptors of dissociation enthalpy or lattice enthalpy trends when bi-component crystals with different molecular composition are being compared, even if the stoichiometry is the same.
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Affiliation(s)
- Inês O. Feliciano
- Centro de Química Estrutural, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal; (I.O.F.); (C.E.S.B.)
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal;
| | - Daniela P. Silva
- Centro de Química Estrutural, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal;
| | - M. Fátima M. Piedade
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal;
- Centro de Química Estrutural, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal;
| | - Carlos E. S. Bernardes
- Centro de Química Estrutural, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal; (I.O.F.); (C.E.S.B.)
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal;
| | - Manuel E. Minas da Piedade
- Centro de Química Estrutural, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal; (I.O.F.); (C.E.S.B.)
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal;
- Correspondence: ; Tel.: +351-217500005
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Repin IA, Loebenberg R, DiBella J, Conceição ACL, Minas da Piedade ME, Ferraz HG, Issa MG, Bou-Chacra NA, Ermida CFM, de Araujo GLB. Exploratory Study on Lercanidipine Hydrochloride Polymorphism: pH-Dependent Solubility Behavior and Simulation of its Impact on Pharmacokinetics. AAPS PharmSciTech 2021; 22:54. [PMID: 33475891 DOI: 10.1208/s12249-021-01923-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Accepted: 01/01/2021] [Indexed: 11/30/2022] Open
Abstract
This work describes an exploratory experimental and in silico study of the influence of polymorphism, particle size, and physiology on the pharmacokinetics of lercanidipine hydrochloride (LHC). Equilibrium and kinetic solubility studies were performed on LHC forms I and II, as a function of pH and buffer composition. GastroPlus® was used to evaluate the potential effect of solubility differences due to polymorphism, particle size, and physiological conditions, on the drug pharmacokinetics. The results indicated that solubilities of LHC polymorphs are strongly dependent on the composition and pH of the buffer media. The concentration ratio (CI/CII) is particularly large for chloride buffer (CI/CII = 3.3-3.9) and exhibits a slightly decreasing tendency with the pH increase for all other buffers. Based on solubility alone, a higher bioavailability of form I might be expected. However, exploratory PBPK simulations suggested that (i) under usual fasted (pH 1.3) and fed (pH 4.9) gastric conditions, the two polymorphs have similar bioavailability, regardless of the particle size; (ii) at high gastric pH in the fasted state (e.g., pH 3.0), the bioavailability of form II can be considerably lower than that of form I, unless the particle size is < 20 μm. This study demonstrates the importance of investigating the effect of the buffer nature when evaluating the solubility of ionizable polymorphic substances. It also showcases the benefits of using PBPK simulations, to assess the risk and pharmacokinetic relevance of different solubility and particle size between crystal forms, for diverse physiological conditions.
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Joseph A, Rodrigues Alves JS, Bernardes CES, Piedade MFM, Minas da Piedade ME. Tautomer selection through solvate formation: the case of 5-hydroxynicotinic acid. CrystEngComm 2019. [DOI: 10.1039/c8ce02108b] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Different 5-hydroxynicotinic acid tautomers were selectively captured through solvate formation. The selectivity is lost once the memory of solvation is erased by removing the solvent from the crystal lattice.
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Affiliation(s)
- Abhinav Joseph
- Centro de Química e Bioquímica and Centro de Química Estrutural
- Faculdade de Ciências
- Universidade de Lisboa
- 1749-016 Lisboa
- Portugal
| | - Joana S. Rodrigues Alves
- Centro de Química e Bioquímica and Centro de Química Estrutural
- Faculdade de Ciências
- Universidade de Lisboa
- 1749-016 Lisboa
- Portugal
| | - Carlos E. S. Bernardes
- Centro de Química e Bioquímica and Centro de Química Estrutural
- Faculdade de Ciências
- Universidade de Lisboa
- 1749-016 Lisboa
- Portugal
| | - M. Fátima M. Piedade
- Centro de Química e Bioquímica and Centro de Química Estrutural
- Faculdade de Ciências
- Universidade de Lisboa
- 1749-016 Lisboa
- Portugal
| | - Manuel E. Minas da Piedade
- Centro de Química e Bioquímica and Centro de Química Estrutural
- Faculdade de Ciências
- Universidade de Lisboa
- 1749-016 Lisboa
- Portugal
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Simões RG, Bernardes CES, Joseph A, M Piedade MF, Kraus W, Emmerling F, Diogo HP, Minas da Piedade ME. Polymorphism in Simvastatin: Twinning, Disorder, and Enantiotropic Phase Transitions. Mol Pharm 2018; 15:5349-5360. [PMID: 30230340 DOI: 10.1021/acs.molpharmaceut.8b00818] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Simvastatin is one of the most widely used active pharmaceutical ingredients for the treatment of hyperlipidemias. Because the compound is employed as a solid in drug formulations, particular attention should be given to the characterization of different polymorphs, their stability domains, and the nature of the phase transitions that relate them. In this work, the phase transitions delimiting the stability domains of three previously reported simvastatin forms were investigated from structural, energetics, and dynamical points of view based on single crystal X-ray diffraction (SCXRD), hot stage microscopy (HSM), and differential scanning calorimetry (DSC) experiments (conventional scans and heat capacity measurements), complemented with molecular dynamics (MD) simulations. Previous assignments of the crystal forms were confirmed by SCXRD: forms I and II were found to be orthorhombic ( P212121, Z'/ Z = 1/4) and form III was monoclinic ( P21, Z'/ Z = 2/4). The obtained results further indicated that (i) the transitions between different forms are observed at 235.9 ± 0.1 K (form III → form II) and at 275.2 ± 0.2 K (form II → form I) in DSC runs carried out at 10 K min-1 and close to these values when other types of techniques are used (e.g., HSM). (ii) They are enantiotropic (i.e., there is a transition temperature relating the two phases before fusion at which the stability order is reversed), fast, reversible, with very little hysteresis between heating and cooling modes, and occur under single crystal to single crystal conditions. (iii) A nucleation and growth mechanism seems to be followed since HSM experiments on single crystals evidenced the propagation of an interface, accompanied by a change of birefringence and crystal contraction or expansion (more subtle in the case of form III → form II), when the phase transitions are triggered. (iv) Consistent with the reversible and small hysteresis nature of the phase transitions, the SCXRD results indicated that the molecular packing is very similar in all forms and the main structural differences are associated with conformational changes of the "ester tail". (v) The MD simulations further suggested that the tail is essentially "frozen" in two conformations below the III → II transition temperature, becomes progressively less hindered throughout the stability domain of form II, and acquires a large conformational freedom above the II → I transition. Finally, the fact that these transitions were found to be fast and reversible suggests that polymorphism is unlikely to be a problem for pharmaceutical formulations employing crystalline simvastatin because, if present, the III and II forms will readily convert to form I at ambient temperature.
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Affiliation(s)
- Ricardo G Simões
- Centro de Química e Bioquímica e Centro de Química Estrutural , Faculdade de Ciências Universidade de Lisboa , Campo Grande , 1749-016 Lisboa , Portugal
| | - Carlos E S Bernardes
- Centro de Química e Bioquímica e Centro de Química Estrutural , Faculdade de Ciências Universidade de Lisboa , Campo Grande , 1749-016 Lisboa , Portugal
| | - Abhinav Joseph
- Centro de Química e Bioquímica e Centro de Química Estrutural , Faculdade de Ciências Universidade de Lisboa , Campo Grande , 1749-016 Lisboa , Portugal
| | - M Fátima M Piedade
- Centro de Química e Bioquímica e Centro de Química Estrutural , Faculdade de Ciências Universidade de Lisboa , Campo Grande , 1749-016 Lisboa , Portugal.,Centro de Química Estrutural, Instituto Superior Técnico , Universidade de Lisboa , 1049-001 Lisboa , Portugal
| | - Werner Kraus
- BAM Federal Institute for Materials Research and Testing , Richard-Willstaetter-Strasse 11 , 12489 Berlin , Germany
| | - Franziska Emmerling
- BAM Federal Institute for Materials Research and Testing , Richard-Willstaetter-Strasse 11 , 12489 Berlin , Germany
| | - Hermíno P Diogo
- Centro de Química Estrutural, Instituto Superior Técnico , Universidade de Lisboa , 1049-001 Lisboa , Portugal
| | - Manuel E Minas da Piedade
- Centro de Química e Bioquímica e Centro de Química Estrutural , Faculdade de Ciências Universidade de Lisboa , Campo Grande , 1749-016 Lisboa , Portugal
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Martins FF, Joseph A, Diogo HP, Minas da Piedade ME, Ferreira LP, Carvalho MD, Barroso S, Romão MJ, Calhorda MJ, Martinho PN. Irreversible Magnetic Behaviour Caused by the Thermosalient Phenomenon in an Iron(III) Spin Crossover Complex. Eur J Inorg Chem 2018. [DOI: 10.1002/ejic.201800605] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Frederico F. Martins
- Centro de Química e Bioquímica; Faculdade de Ciências; Universidade de Lisboa; Campo Grande 1749-016 Lisboa Portugal
- BioISI - Biosystems and Integrative Sciences Institute; Faculty of Sciences; Universidade de Lisboa; Campo Grande C8 bdg 1749-016 Lisboa Portugal
| | - Abhinav Joseph
- Centro de Química e Bioquímica; Faculdade de Ciências; Universidade de Lisboa; Campo Grande 1749-016 Lisboa Portugal
- Centro de Química Estrutural; Faculdade de Ciências e Instituto Superior Técnico; Universidade de Lisboa; Campo Grande 1749-016 Lisboa Portugal
| | - Hermínio P. Diogo
- Centro de Química Estrutural; Instituto Superior Técnico; Universidade de Lisboa; 1049-001 Lisboa Portugal
| | - Manuel E. Minas da Piedade
- Centro de Química e Bioquímica; Faculdade de Ciências; Universidade de Lisboa; Campo Grande 1749-016 Lisboa Portugal
- Centro de Química Estrutural; Faculdade de Ciências e Instituto Superior Técnico; Universidade de Lisboa; Campo Grande 1749-016 Lisboa Portugal
| | - Liliana P. Ferreira
- BioISI - Biosystems and Integrative Sciences Institute; Faculty of Sciences; Universidade de Lisboa; Campo Grande C8 bdg 1749-016 Lisboa Portugal
- Department of Physics; University of Coimbra; 3004-516 Coimbra Portugal
| | - Maria Deus Carvalho
- Centro de Química e Bioquímica; Faculdade de Ciências; Universidade de Lisboa; Campo Grande 1749-016 Lisboa Portugal
| | - Sónia Barroso
- UCIBIO, REQUIMTE; Departamento de Química, Faculdade de Ciências e Tecnologia; Universidade Nova de Lisboa; 2829-516 Caparica Portugal
| | - Maria João Romão
- UCIBIO, REQUIMTE; Departamento de Química, Faculdade de Ciências e Tecnologia; Universidade Nova de Lisboa; 2829-516 Caparica Portugal
| | - Maria José Calhorda
- Centro de Química e Bioquímica; Faculdade de Ciências; Universidade de Lisboa; Campo Grande 1749-016 Lisboa Portugal
- BioISI - Biosystems and Integrative Sciences Institute; Faculty of Sciences; Universidade de Lisboa; Campo Grande C8 bdg 1749-016 Lisboa Portugal
| | - Paulo N. Martinho
- Centro de Química e Bioquímica; Faculdade de Ciências; Universidade de Lisboa; Campo Grande 1749-016 Lisboa Portugal
- BioISI - Biosystems and Integrative Sciences Institute; Faculty of Sciences; Universidade de Lisboa; Campo Grande C8 bdg 1749-016 Lisboa Portugal
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Bernardes CES, Garcia C, Pereira F, Mota J, Pereira P, Cebola MJ, Reis CP, Correia I, Piedade MFM, Minas da Piedade ME, Rijo P. Extraction Optimization and Structural and Thermal Characterization of the Antimicrobial Abietane 7α-Acetoxy-6β-hydroxyroyleanone. Mol Pharm 2018; 15:1412-1419. [PMID: 29494159 DOI: 10.1021/acs.molpharmaceut.7b00892] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The abietane 7α-acetoxy-6β-hydroxyroyleanone (AHR), obtained from plant extracts, is an attractive lead for drug development, given its known antimicrobial properties. Two basic requirements to establish any compound as a new drug are the development of a convenient extraction process and the characterization of its structural and thermal properties. In this work seven different methods were tested to optimize the extraction of AHR from Plectranthus grandidentatus. Supercritical fluid extraction (SFE) proved to be the method of choice, delivering an amount of AHR (57.351 μg·mg-1) approximately six times higher than the second best method (maceration in acetone; 9.77 μg·mg-1). Single crystal X-ray diffraction analysis of the ARH molecular and crystal structure carried out at 167 ± 2 K and 296 ± 2 K showed only a single phase, here dubbed form III (orthorhombic space group P21212), at those temperatures. The presence of two other polymorphs above room temperature was, however, evidenced by differential scanning calorimetry (DSC). The three forms are enantiotropically related, with the form III → form II and form II → form I transitions occurring at 333.5 ± 1.6 K and 352.0 ± 1.6 K, respectively. The fact that the transitions are reversible suggests that polymorphism is not likely to be an issue in the development pharmaceutical formulations based on ARH. DSC experiments also showed that the compound decomposes on melting at 500.8 ± 0.8 K. Melting should therefore be avoided if, for example, strategies to improve solubility based on the production of glassy materials or solid dispersions are considered.
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Affiliation(s)
- Carlos E S Bernardes
- Centro de Química e Bioquímica e Centro de Química Estrutural, Faculdade de Ciências , Universidade de Lisboa , 1649-016 Lisboa , Portugal
| | - Catarina Garcia
- Research Center for Biosciences & Health Technologies (CBIOS) , Universidade Lusófona de Humanidades e Tecnologias , 1749-024 Lisboa , Portugal.,Department of Biomedical Sciences, Faculty of Pharmacy , University of Alcalá , Carretera A2, Km 33.600-Campus Universitario , 28871 Alcalá de Henares , Spain
| | - Filipe Pereira
- Research Center for Biosciences & Health Technologies (CBIOS) , Universidade Lusófona de Humanidades e Tecnologias , 1749-024 Lisboa , Portugal.,Department of Biomedical Sciences, Faculty of Pharmacy , University of Alcalá , Carretera A2, Km 33.600-Campus Universitario , 28871 Alcalá de Henares , Spain
| | - Joana Mota
- Research Center for Biosciences & Health Technologies (CBIOS) , Universidade Lusófona de Humanidades e Tecnologias , 1749-024 Lisboa , Portugal
| | - P Pereira
- Research Center for Biosciences & Health Technologies (CBIOS) , Universidade Lusófona de Humanidades e Tecnologias , 1749-024 Lisboa , Portugal.,Center for Natural Resources and Environment (CERENA), Instituto Superior Técnico (IST) , Universidade de Lisboa , Avenida Rovisco Pais , 1049-001 Lisboa , Portugal
| | - Maria J Cebola
- Research Center for Biosciences & Health Technologies (CBIOS) , Universidade Lusófona de Humanidades e Tecnologias , 1749-024 Lisboa , Portugal.,Escola Superior Náutica Infante D. Henrique (ENIDH) , Avenida Engenheiro Bonneville Franco , 2770-058 Paço de Arcos , Portugal
| | - Catarina P Reis
- Research Center for Biosciences & Health Technologies (CBIOS) , Universidade Lusófona de Humanidades e Tecnologias , 1749-024 Lisboa , Portugal.,Instituto de Investigação do Medicamento (iMed.ULisboa), Faculdade de Farmácia , Universidade de Lisboa , 1649-003 Lisboa , Portugal
| | - Isabel Correia
- Centro de Química Estrutural, Instituto Superior Técnico , Universidade de Lisboa , 1049-001 Lisboa , Portugal
| | - M Fátima M Piedade
- Centro de Química e Bioquímica e Centro de Química Estrutural, Faculdade de Ciências , Universidade de Lisboa , 1649-016 Lisboa , Portugal.,Centro de Química Estrutural, Instituto Superior Técnico , Universidade de Lisboa , 1049-001 Lisboa , Portugal
| | - Manuel E Minas da Piedade
- Centro de Química e Bioquímica e Centro de Química Estrutural, Faculdade de Ciências , Universidade de Lisboa , 1649-016 Lisboa , Portugal
| | - Patrícia Rijo
- Research Center for Biosciences & Health Technologies (CBIOS) , Universidade Lusófona de Humanidades e Tecnologias , 1749-024 Lisboa , Portugal.,Instituto de Investigação do Medicamento (iMed.ULisboa), Faculdade de Farmácia , Universidade de Lisboa , 1649-003 Lisboa , Portugal
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Reid JESJ, Bernardes CES, Agapito F, Martins F, Shimizu S, Minas da Piedade ME, Walker AJ. Structure-property relationships in protic ionic liquids: a study of solvent-solvent and solvent-solute interactions. Phys Chem Chem Phys 2018; 19:28133-28138. [PMID: 29022017 DOI: 10.1039/c7cp05076c] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The ionic nature of a functionalized protic ionic liquid cannot be rationalized simply through the differences in aqueous proton dissociation constants between the acid precursor and the conjugate acid of the base precursor. The extent of proton transfer, i.e. the equilibrium ionicity, of a tertiary ammonium acetate protic ionic liquid can be significantly increased by introducing an hydroxyl functional group on the cation, compared to the alkyl or amino-functionalized analogues. This increase in apparent ionic nature correlates well with variations in solvent-solute and solvent-solvent interaction parameters, as well as with physicochemical properties such as viscosity.
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Affiliation(s)
- Joshua E S J Reid
- York Structural Biology Laboratory, Department of Chemistry, University of York, Heslington, York YO10 5DD, UK
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Reid JESJ, Agapito F, Bernardes CES, Martins F, Walker AJ, Shimizu S, Minas da Piedade ME. Structure–property relationships in protic ionic liquids: a thermochemical study. Phys Chem Chem Phys 2017; 19:19928-19936. [DOI: 10.1039/c7cp02230a] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
How does cation functionality influence the strength of intermolecular interactions in protic ionic liquids (PILs)? Quantifying the energetics of PILs can be an invaluable tool to answer this fundamental question.
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Affiliation(s)
- Joshua E. S. J. Reid
- York Structural Biology Laboratory
- Department of Chemistry
- University of York
- Heslington
- York
| | - Filipe Agapito
- Centro de Química e Bioquímica e Departamento de Química e Bioquímica
- Faculdade de Ciências
- Universidade de Lisboa
- 1749-016 Lisboa
- Portugal
| | - Carlos E. S. Bernardes
- Centro de Química e Bioquímica e Departamento de Química e Bioquímica
- Faculdade de Ciências
- Universidade de Lisboa
- 1749-016 Lisboa
- Portugal
| | - Filomena Martins
- Centro de Química e Bioquímica e Departamento de Química e Bioquímica
- Faculdade de Ciências
- Universidade de Lisboa
- 1749-016 Lisboa
- Portugal
| | | | - Seishi Shimizu
- York Structural Biology Laboratory
- Department of Chemistry
- University of York
- Heslington
- York
| | - Manuel E. Minas da Piedade
- Centro de Química e Bioquímica e Departamento de Química e Bioquímica
- Faculdade de Ciências
- Universidade de Lisboa
- 1749-016 Lisboa
- Portugal
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10
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Dario MF, Oliveira CA, Cordeiro LR, Rosado C, Mariz IDFA, Maçôas E, Santos MSC, Minas da Piedade ME, Baby AR, Velasco MVR. Stability and safety of quercetin-loaded cationic nanoemulsion: In vitro and in vivo assessments. Colloids Surf A Physicochem Eng Asp 2016. [DOI: 10.1016/j.colsurfa.2016.07.010] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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11
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Vicente AI, Joseph A, Ferreira LP, de Deus Carvalho M, Rodrigues VHN, Duttine M, Diogo HP, Minas da Piedade ME, Calhorda MJ, Martinho PN. Dynamic spin interchange in a tridentate Fe(iii) Schiff-base compound. Chem Sci 2016; 7:4251-4258. [PMID: 30155072 PMCID: PMC6013817 DOI: 10.1039/c5sc04577k] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2015] [Accepted: 03/16/2016] [Indexed: 11/21/2022] Open
Abstract
The thermosalient effect is still a rare and poorly understood phenomenon, where crystals suddenly jump, bend, twist or explode upon undergoing a thermally activated phase transition. The synthesis and characterisation of the new spin transition Fe(iii) compound [Fe(5-Br-salEen)2][ClO4] (salEen = N-ethyl-N-(2-aminoethyl)salicylaldiminate) is described and its thermosalient behaviour reported. It is the first example of a thermosalient effect with a spin transition and magnetic, calorimetric, diffraction, microscopy and computational studies are used to characterise these effects. Both thermosalient effect and spin transition occur around 320 K upon heating and are accompanied by an anisotropic unit cell change with conservation of crystal symmetry that causes a large enough stress of the crystal lattice to induce crystal explosion. This stress can ultimately be traced back to a diffusionless and distortive structural perturbation resulting in a coupled spin transition-thermosalient effect.
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Affiliation(s)
- Ana I Vicente
- Centro de Química e Bioquímica , Faculdade de Ciências , Universidade de Lisboa , Campo Grande , 1749-016 Lisboa , Portugal .
| | - Abhinav Joseph
- Centro de Química e Bioquímica , Faculdade de Ciências , Universidade de Lisboa , Campo Grande , 1749-016 Lisboa , Portugal .
| | - Liliana P Ferreira
- BioISI , Faculdade de Ciências , Universidade de Lisboa , Campo Grande , 1749-016 Lisboa , Portugal
- Department of Physics , University of Coimbra , 3004-516 Coimbra , Portugal
| | - Maria de Deus Carvalho
- Centro de Química e Bioquímica , Faculdade de Ciências , Universidade de Lisboa , Campo Grande , 1749-016 Lisboa , Portugal .
| | | | - Mathieu Duttine
- CNRS , Université de Bordeaux , ICMCB , 87 avenue du Dr. A. Schweitzer , Pessac F-33608 , France
| | - Hermínio P Diogo
- Centro de Química Estrutural , Instituto Superior Técnico , Universidade de Lisboa , 1049-001 Lisboa , Portugal
| | - Manuel E Minas da Piedade
- Centro de Química e Bioquímica , Faculdade de Ciências , Universidade de Lisboa , Campo Grande , 1749-016 Lisboa , Portugal .
| | - Maria José Calhorda
- Centro de Química e Bioquímica , Faculdade de Ciências , Universidade de Lisboa , Campo Grande , 1749-016 Lisboa , Portugal .
| | - Paulo N Martinho
- Centro de Química e Bioquímica , Faculdade de Ciências , Universidade de Lisboa , Campo Grande , 1749-016 Lisboa , Portugal .
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12
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Dario MF, Santos MSC, Viana AS, Arêas EP, Bou-Chacra NA, Oliveira MC, da Piedade MEM, Baby AR, Velasco MVR. A high loaded cationic nanoemulsion for quercetin delivery obtained by sub-PIT method. Colloids Surf A Physicochem Eng Asp 2016. [DOI: 10.1016/j.colsurfa.2015.10.031] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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13
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Vitorino J, Leal JP, Minas da Piedade ME. Gas-Phase Affinity Scales for Typical Ionic Liquid Moieties Determined by using Cooks' Kinetic Method. Chemphyschem 2015; 16:1969-77. [PMID: 25891168 DOI: 10.1002/cphc.201500101] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Indexed: 11/12/2022]
Abstract
Gas-phase affinity studies based on cations and anions commonly present in ionic liquid structures, give quantitative information about the magnitude of the interactions holding the two species together when ILs are formed. They also provide clues on how these interactions depend on the nature of the cationic and anionic moieties. In the present work, mass spectrometric experiments, performed using electrospray ionization quadrupole ion-trap and Fourier transform ion cyclotron resonance mass spectrometry, were used to obtain two affinity scales by Cooks' kinetic method: one scale for the various cations for the bis(trifluoromethylsulfonyl)imide anion, [NTf2 ](-) , and another for the different anions for the 1-butyl-3-methylimidazolium cation, [C4 mim](+) . The obtained results are compared with previously reported data and discussed in terms of the structural characteristics of the different cationic and anionic species.
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Affiliation(s)
- Joana Vitorino
- Centro de Química e Bioquímica e Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1649-016 Lisboa (Portugal)
| | - João Paulo Leal
- Centro de Química e Bioquímica e Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1649-016 Lisboa (Portugal).,Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, 2695-068 Bobadela (Portugal)
| | - Manuel E Minas da Piedade
- Centro de Química e Bioquímica e Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1649-016 Lisboa (Portugal).
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14
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Simões RG, Agapito F, Diogo HP, da Piedade MEM. Enthalpy of Formation of Anisole: Implications for the Controversy on the O–H Bond Dissociation Enthalpy in Phenol. J Phys Chem A 2014; 118:11026-32. [DOI: 10.1021/jp507267f] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ricardo G. Simões
- Centro
de Química e Bioquímica e Departamento de Química
e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
| | - Filipe Agapito
- Centro
de Química e Bioquímica e Departamento de Química
e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
| | - Hermínio P. Diogo
- Centro
de Química Estrutural, Instituto Superior Técnico, Universidade de Lisboa,1049-001 Lisboa, Portugal
| | - Manuel E. Minas da Piedade
- Centro
de Química e Bioquímica e Departamento de Química
e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
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15
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Bernardes CES, Canongia Lopes JN, da Piedade MEM. All-Atom Force Field for Molecular Dynamics Simulations on Organotransition Metal Solids and Liquids. Application to M(CO)n (M = Cr, Fe, Ni, Mo, Ru, or W) Compounds. J Phys Chem A 2013; 117:11107-13. [DOI: 10.1021/jp407739h] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Carlos E. S. Bernardes
- Centro
de Química e Bioquímica e Departamento de Química
e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
- Centro
de Química Estrutural, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal
| | - José. N. Canongia Lopes
- Centro
de Química Estrutural, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal
| | - Manuel E. Minas da Piedade
- Centro
de Química e Bioquímica e Departamento de Química
e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
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16
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Affiliation(s)
- Ricardo G. Simões
- Departamento
de Química
e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1649-016 Lisboa, Portugal
| | - Carlos E. S. Bernardes
- Departamento
de Química
e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1649-016 Lisboa, Portugal
- Centro de Química Estrutural,
Complexo Interdisciplinar, Instituto Superior Técnico, 1049-001 Lisboa, Portugal
| | - Hermínio P. Diogo
- Centro de Química Estrutural,
Complexo Interdisciplinar, Instituto Superior Técnico, 1049-001 Lisboa, Portugal
| | - Filipe Agapito
- Departamento
de Química
e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1649-016 Lisboa, Portugal
| | - Manuel E. Minas da Piedade
- Departamento
de Química
e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1649-016 Lisboa, Portugal
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17
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Bernardes CES, Minas da Piedade ME, Canongia Lopes JN. Polymorphism in 4′-Hydroxyacetophenone: A Molecular Dynamics Simulation Study. J Phys Chem B 2012; 116:5179-84. [DOI: 10.1021/jp300341f] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Carlos E. S. Bernardes
- Centro de Química Estrutural,
Instituto Superior Técnico, Universidade Técnica de Lisboa, 1049 001 Lisboa, Portugal
- Centro de Química e Bioquímica
e Departamento de Química e Bioquímica, Faculdade de
Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
| | - Manuel E. Minas da Piedade
- Centro de Química e Bioquímica
e Departamento de Química e Bioquímica, Faculdade de
Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
| | - José N. Canongia Lopes
- Centro de Química Estrutural,
Instituto Superior Técnico, Universidade Técnica de Lisboa, 1049 001 Lisboa, Portugal
- Instituto de Tecnologia Química
e Biológica, Universidade Nova de Lisboa, Av. República Ap. 127, 2780 901 Oeiras, Portugal
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18
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Vitorino J, Bernardes CES, Minas da Piedade ME. A general strategy for the experimental study of the thermochemistry of protic ionic liquids: enthalpy of formation and vaporisation of 1-methylimidazolium ethanoate. Phys Chem Chem Phys 2012; 14:4440-6. [DOI: 10.1039/c2cp40213k] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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19
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Hagmeyer D, Ruesing J, Fenske T, Klein HW, Schmuck C, Schrader W, Piedade MEMD, Epple M. Direct experimental observation of the aggregation of α-amino acids into 100–200 nm clusters in aqueous solution. RSC Adv 2012. [DOI: 10.1039/c2ra01352e] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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20
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Bernardes CES, Minas da Piedade ME, Canongia Lopes JN. The Structure of Aqueous Solutions of a Hydrophilic Ionic Liquid: The Full Concentration Range of 1-Ethyl-3-methylimidazolium Ethylsulfate and Water. J Phys Chem B 2011; 115:2067-74. [DOI: 10.1021/jp1113202] [Citation(s) in RCA: 129] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Carlos E. S. Bernardes
- Centro de Química Estrutural, Instituto Superior Técnico, UTL, 1049-001 Lisboa, Portugal
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1649-016 Lisboa, Portugal
| | - Manuel E. Minas da Piedade
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1649-016 Lisboa, Portugal
| | - José N. Canongia Lopes
- Centro de Química Estrutural, Instituto Superior Técnico, UTL, 1049-001 Lisboa, Portugal
- Instituto de Tecnologia Química e Biológica, www.itqb.unl.pt, UNL, Av. República Ap. 127, 2780-901 Oeiras, Portugal
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Picciochi R, Diogo HP, Minas da Piedade ME. Thermodynamic Characterization of Three Polymorphic Forms of Piracetam. J Pharm Sci 2011; 100:594-603. [DOI: 10.1002/jps.22294] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2010] [Revised: 06/15/2010] [Accepted: 06/16/2010] [Indexed: 11/06/2022]
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22
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Vitorino J, Leal JP, Licence P, Lovelock KRJ, Gooden PN, Minas da Piedade ME, Shimizu K, Rebelo LPN, Canongia Lopes JN. Vaporisation of a Dicationic Ionic Liquid Revisited. Chemphyschem 2010; 11:3673-7. [DOI: 10.1002/cphc.201000723] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Joana Vitorino
- Departamento de Química e Bioquímica/FCUL, 1649‐016 Lisboa (Portugal)
- Unidade de Ciências Químicas e Radiofarmacêuticas/ITN, 2686‐953, Sacavém (Portugal)
| | - João P. Leal
- Departamento de Química e Bioquímica/FCUL, 1649‐016 Lisboa (Portugal)
- Unidade de Ciências Químicas e Radiofarmacêuticas/ITN, 2686‐953, Sacavém (Portugal)
| | - Peter Licence
- School of Chemistry, University of Nottingham, Nottingham, NG7 2RD (UK)
| | | | - Peter N. Gooden
- School of Chemistry, University of Nottingham, Nottingham, NG7 2RD (UK)
| | | | - Karina Shimizu
- Centro de Química Estrutural/IST, Av. Rovisco Pais 1049 001 Lisboa (Portugal), Fax: (+351) 218 464 455 http://cqe.ist.utl.pt
| | - Luís P. N. Rebelo
- Instituto de Tecnologia Química e Biológica/UNL, Av. República, Apartado 127, 2780 901 Oeiras (Portugal) http://www.itqb.unl.pt
| | - José N. Canongia Lopes
- Centro de Química Estrutural/IST, Av. Rovisco Pais 1049 001 Lisboa (Portugal), Fax: (+351) 218 464 455 http://cqe.ist.utl.pt
- Instituto de Tecnologia Química e Biológica/UNL, Av. República, Apartado 127, 2780 901 Oeiras (Portugal) http://www.itqb.unl.pt
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23
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Leskiv M, Bernardes CES, Minas da Piedade ME, Canongia Lopes JN. Energetics of Aqueous Solutions of the Ionic Liquid 1-Ethyl-3-methylimidazolium Ethylsulfate. J Phys Chem B 2010; 114:13179-88. [DOI: 10.1021/jp1067473] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Miroslav Leskiv
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1649-016 Lisboa, Portugal, Centro de Química Estrutural, Complexo Interdisciplinar, Instituto Superior Técnico da Universidade Técnica de Lisboa, 1049-001 Lisboa, Portugal, and Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Avenida República, Apartado 127, 2780-901 Oeiras, Portugal
| | - Carlos E. S. Bernardes
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1649-016 Lisboa, Portugal, Centro de Química Estrutural, Complexo Interdisciplinar, Instituto Superior Técnico da Universidade Técnica de Lisboa, 1049-001 Lisboa, Portugal, and Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Avenida República, Apartado 127, 2780-901 Oeiras, Portugal
| | - Manuel E. Minas da Piedade
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1649-016 Lisboa, Portugal, Centro de Química Estrutural, Complexo Interdisciplinar, Instituto Superior Técnico da Universidade Técnica de Lisboa, 1049-001 Lisboa, Portugal, and Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Avenida República, Apartado 127, 2780-901 Oeiras, Portugal
| | - José N. Canongia Lopes
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1649-016 Lisboa, Portugal, Centro de Química Estrutural, Complexo Interdisciplinar, Instituto Superior Técnico da Universidade Técnica de Lisboa, 1049-001 Lisboa, Portugal, and Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Avenida República, Apartado 127, 2780-901 Oeiras, Portugal
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Vitorino J, Leal JP, Minas da Piedade ME, Canongia Lopes JN, Esperança JMSS, Rebelo LPN. The Nature of Protic Ionic Liquids in the Gas Phase Revisited: Fourier Transform Ion Cyclotron Resonance Mass Spectrometry Study of 1,1,3,3-Tetramethylguanidinium Chloride. J Phys Chem B 2010; 114:8905-9. [DOI: 10.1021/jp1042798] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Joana Vitorino
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1649-016 Lisboa, Portugal, Unidade de Ciências Químicas e Radiofarmacêuticas, Instituto Tecnológico e Nuclear, 2686-953 Sacavém, Portugal, Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Av. República, Apartado 127, 2780-901 Oeiras, Portugal (www.itqb.unl.pt), and Centro de Química Estrutural, Complexo Interdisciplinar, Instituto Superior Técnico da Universidade Técnica de Lisboa, 1049-001
| | - João P. Leal
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1649-016 Lisboa, Portugal, Unidade de Ciências Químicas e Radiofarmacêuticas, Instituto Tecnológico e Nuclear, 2686-953 Sacavém, Portugal, Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Av. República, Apartado 127, 2780-901 Oeiras, Portugal (www.itqb.unl.pt), and Centro de Química Estrutural, Complexo Interdisciplinar, Instituto Superior Técnico da Universidade Técnica de Lisboa, 1049-001
| | - Manuel E. Minas da Piedade
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1649-016 Lisboa, Portugal, Unidade de Ciências Químicas e Radiofarmacêuticas, Instituto Tecnológico e Nuclear, 2686-953 Sacavém, Portugal, Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Av. República, Apartado 127, 2780-901 Oeiras, Portugal (www.itqb.unl.pt), and Centro de Química Estrutural, Complexo Interdisciplinar, Instituto Superior Técnico da Universidade Técnica de Lisboa, 1049-001
| | - José N. Canongia Lopes
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1649-016 Lisboa, Portugal, Unidade de Ciências Químicas e Radiofarmacêuticas, Instituto Tecnológico e Nuclear, 2686-953 Sacavém, Portugal, Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Av. República, Apartado 127, 2780-901 Oeiras, Portugal (www.itqb.unl.pt), and Centro de Química Estrutural, Complexo Interdisciplinar, Instituto Superior Técnico da Universidade Técnica de Lisboa, 1049-001
| | - José M. S. S. Esperança
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1649-016 Lisboa, Portugal, Unidade de Ciências Químicas e Radiofarmacêuticas, Instituto Tecnológico e Nuclear, 2686-953 Sacavém, Portugal, Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Av. República, Apartado 127, 2780-901 Oeiras, Portugal (www.itqb.unl.pt), and Centro de Química Estrutural, Complexo Interdisciplinar, Instituto Superior Técnico da Universidade Técnica de Lisboa, 1049-001
| | - Luís Paulo N. Rebelo
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1649-016 Lisboa, Portugal, Unidade de Ciências Químicas e Radiofarmacêuticas, Instituto Tecnológico e Nuclear, 2686-953 Sacavém, Portugal, Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Av. República, Apartado 127, 2780-901 Oeiras, Portugal (www.itqb.unl.pt), and Centro de Química Estrutural, Complexo Interdisciplinar, Instituto Superior Técnico da Universidade Técnica de Lisboa, 1049-001
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Affiliation(s)
- Elsa M. Gonçalves
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1649-016 Lisboa, Portugal, and Centro de Química Estrutural, Complexo Interdisciplinar, Instituto Superior Técnico da Universidade Técnica de Lisboa, 1049-001 Lisboa, Portugal
| | - Carlos E. S. Bernardes
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1649-016 Lisboa, Portugal, and Centro de Química Estrutural, Complexo Interdisciplinar, Instituto Superior Técnico da Universidade Técnica de Lisboa, 1049-001 Lisboa, Portugal
| | - Hermínio P. Diogo
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1649-016 Lisboa, Portugal, and Centro de Química Estrutural, Complexo Interdisciplinar, Instituto Superior Técnico da Universidade Técnica de Lisboa, 1049-001 Lisboa, Portugal
| | - Manuel E. Minas da Piedade
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1649-016 Lisboa, Portugal, and Centro de Química Estrutural, Complexo Interdisciplinar, Instituto Superior Técnico da Universidade Técnica de Lisboa, 1049-001 Lisboa, Portugal
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Santos RC, Figueira RMBBM, Piedade MFM, Diogo HP, Minas da Piedade ME. Energetics and Structure of Hydroxynicotinic Acids. Crystal Structures of 2-, 4-, 6-Hydroxynicotinic and 5-Chloro-6-hydroxynicotinic Acids. J Phys Chem B 2009; 113:14291-309. [DOI: 10.1021/jp906908n] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Rui C. Santos
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1649-016 Lisboa, Portugal, and Centro de Química Estrutural, Complexo Interdisciplinar, Instituto Superior Técnico da Universidade Técnica de Lisboa, 1049-001 Lisboa, Portugal
| | - Rita M. B. B. M. Figueira
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1649-016 Lisboa, Portugal, and Centro de Química Estrutural, Complexo Interdisciplinar, Instituto Superior Técnico da Universidade Técnica de Lisboa, 1049-001 Lisboa, Portugal
| | - M. Fátima M. Piedade
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1649-016 Lisboa, Portugal, and Centro de Química Estrutural, Complexo Interdisciplinar, Instituto Superior Técnico da Universidade Técnica de Lisboa, 1049-001 Lisboa, Portugal
| | - Hermínio P. Diogo
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1649-016 Lisboa, Portugal, and Centro de Química Estrutural, Complexo Interdisciplinar, Instituto Superior Técnico da Universidade Técnica de Lisboa, 1049-001 Lisboa, Portugal
| | - Manuel E. Minas da Piedade
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1649-016 Lisboa, Portugal, and Centro de Química Estrutural, Complexo Interdisciplinar, Instituto Superior Técnico da Universidade Técnica de Lisboa, 1049-001 Lisboa, Portugal
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Leal JP, da Piedade MEM, Canongia Lopes JN, Tomaszowska AA, Esperança JMSS, Rebelo LPN, Seddon KR. Bridging the gap between ionic liquids and molten salts: group 1 metal salts of the bistriflamide anion in the gas phase. J Phys Chem B 2009; 113:3491-8. [PMID: 19278265 DOI: 10.1021/jp811039b] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Fourier transform ion cyclotron resonance mass spectrometry experiments showed that liquid Group 1 metal salts of the bistriflamide anion undergoing reduced-pressure distillation exhibit a remarkable behavior that is in transition between that of the vapor-liquid equilibrium characteristics of aprotic ionic liquids and that of the Group 1 metal halides: the unperturbed vapors resemble those of aprotic ionic liquids, in the sense that they are essentially composed of discrete ion pairs. However, the formation of large aggregates through a succession of ion-molecule reactions is closer to what might be expected for Group 1 metal halides. Similar experiments were also carried out with bis{(trifluoromethyl)sulfonyl}amine to investigate the effect of H(+), which despite being the smallest Group 1 cation, is generally regarded as a nonmetal species. In this case, instead of the complex ion-molecule reaction pattern found for the vapors of Group 1 metal salts, an equilibrium similar to those observed for aprotic ionic liquids was observed.
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Affiliation(s)
- João P Leal
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, Lisboa, Portugal
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Picciochi R, Canongia Lopes JN, Diogo HP, Minas da Piedade ME. Experimental and Molecular Dynamics Simulation Study of the Sublimation Energetics of Cyclopentadienyltricarbonylmanganese (Cymantrene). J Phys Chem A 2008; 112:10429-34. [DOI: 10.1021/jp805607d] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Ricardo Picciochi
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1649-016 Lisboa, Portugal, and Centro de Química Estrutural, Complexo Interdisciplinar, Instituto Superior Técnico, TULisbon, 1049-001 Lisboa, Portugal
| | - José N. Canongia Lopes
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1649-016 Lisboa, Portugal, and Centro de Química Estrutural, Complexo Interdisciplinar, Instituto Superior Técnico, TULisbon, 1049-001 Lisboa, Portugal
| | - Hermínio P. Diogo
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1649-016 Lisboa, Portugal, and Centro de Química Estrutural, Complexo Interdisciplinar, Instituto Superior Técnico, TULisbon, 1049-001 Lisboa, Portugal
| | - Manuel E. Minas da Piedade
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1649-016 Lisboa, Portugal, and Centro de Química Estrutural, Complexo Interdisciplinar, Instituto Superior Técnico, TULisbon, 1049-001 Lisboa, Portugal
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Bernardes CES, Minas da Piedade ME. Energetics of the O−H Bond and of Intramolecular Hydrogen Bonding in HOC6H4C(O)Y (Y = H, CH3, CH2CH═CH2, C≡CH, CH2F, NH2, NHCH3, NO2, OH, OCH3, OCN, CN, F, Cl, SH, and SCH3) Compounds. J Phys Chem A 2008; 112:10029-39. [DOI: 10.1021/jp804455u] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Carlos E. S. Bernardes
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1649-016 Lisboa, Portugal
| | - Manuel E. Minas da Piedade
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1649-016 Lisboa, Portugal
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Lousada CM, Pinto SS, Canongia Lopes JN, Minas da Piedade MF, Diogo HP, Minas da Piedade ME. Experimental and Molecular Dynamics Simulation Study of the Sublimation and Vaporization Energetics of Iron Metalocenes. Crystal Structures of Fe(η5-C5H4CH3)2 and Fe[(η5-(C5H5)(η5-C5H4CHO)]. J Phys Chem A 2008; 112:2977-87. [DOI: 10.1021/jp7107818] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Cláudio M. Lousada
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1649-016 Lisboa, Portugal, and Centro de Química Estrutural, Complexo Interdisciplinar, Instituto Superior Técnico da Universidade Técnica de Lisboa, 1049-001 Lisboa, Portugal
| | - Susana S. Pinto
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1649-016 Lisboa, Portugal, and Centro de Química Estrutural, Complexo Interdisciplinar, Instituto Superior Técnico da Universidade Técnica de Lisboa, 1049-001 Lisboa, Portugal
| | - José N. Canongia Lopes
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1649-016 Lisboa, Portugal, and Centro de Química Estrutural, Complexo Interdisciplinar, Instituto Superior Técnico da Universidade Técnica de Lisboa, 1049-001 Lisboa, Portugal
| | - M. Fátima Minas da Piedade
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1649-016 Lisboa, Portugal, and Centro de Química Estrutural, Complexo Interdisciplinar, Instituto Superior Técnico da Universidade Técnica de Lisboa, 1049-001 Lisboa, Portugal
| | - Hermínio P. Diogo
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1649-016 Lisboa, Portugal, and Centro de Química Estrutural, Complexo Interdisciplinar, Instituto Superior Técnico da Universidade Técnica de Lisboa, 1049-001 Lisboa, Portugal
| | - Manuel E. Minas da Piedade
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1649-016 Lisboa, Portugal, and Centro de Química Estrutural, Complexo Interdisciplinar, Instituto Superior Técnico da Universidade Técnica de Lisboa, 1049-001 Lisboa, Portugal
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Abstract
Combustion calorimetry studies were used to determine the standard molar enthalpies of formation of o-, m-, and p-cresols, at 298.15 K, in the condensed state as Delta(f)H(m) degrees (o-CH(3)C(6)H(4)OH,cr) = -204.2 +/- 2.7 kJ.mol(-1), Delta(f)H(m) degrees (m-CH(3)C(6)H(4)OH,l) = -196.6 +/- 2.1 kJ.mol(-1), and Delta(f)H(m) degrees (p-CH(3)C(6)H(4)OH,cr) = -202.2 +/- 3.0 kJ.mol(-1). Calvet drop calorimetric measurements led to the following enthalpy of sublimation and vaporization values at 298.15 K: Delta(sub)H(m) degrees (o-CH(3)C(6)H(4)OH) = 73.74 +/- 0.46 kJ.mol(-1), Delta(vap)H(m) degrees (m-CH(3)C(6)H(4)OH) = 64.96 +/- 0.69 kJ.mol(-1), and Delta(sub)H(m) degrees (p-CH(3)C(6)H(4)OH) = 73.13 +/- 0.56 kJ.mol(-1). From the obtained Delta(f)H(m) degrees (l/cr) and Delta(vap)H(m) degrees /Delta(sub)H(m) degrees values, it was possible to derive Delta(f)H(m) degrees (o-CH(3)C(6)H(4)OH,g) = -130.5 +/- 2.7 kJ.mol(-1), Delta(f)H(m) degrees (m-CH(3)C(6)H(4)OH,g) = -131.6 +/- 2.2 kJ.mol(-1), and Delta(f)H(m) degrees (p-CH(3)C(6)H(4)OH,g) = -129.1 +/- 3.1 kJ.mol(-1). These values, together with the enthalpies of isodesmic and isogyric gas-phase reactions predicted by the B3LYP/cc-pVDZ, B3LYP/cc-pVTZ, B3P86/cc-pVDZ, B3P86/cc-pVTZ, MPW1PW91/cc-pVTZ, CBS-QB3, and CCSD/cc-pVDZ//B3LYP/cc-pVTZ methods, were used to obtain the differences between the enthalpy of formation of the phenoxyl radical and the enthalpies of formation of the three methylphenoxyl radicals: Delta(f)H(m) degrees (C(6)H(5)O*,g) - Delta(f)H(m) degrees (o-CH(3)C(6)H(4)O*,g) = 42.2 +/- 2.8 kJ.mol(-1), Delta(f)H(m) degrees (C(6)H(5)O*,g) - Delta(f)H(m) degrees (m-CH(3)C(6)H(4)O*,g) = 36.1 +/- 2.4 kJ.mol(-1), and Delta(f)H(m) degrees (C(6)H(5)O*,g) - Delta(f)H(m) degrees (p-CH(3)C(6)H(4)O*,g) = 38.6 +/- 3.2 kJ.mol(-1). The corresponding differences in O-H bond dissociation enthalpies were also derived as DH degrees (C(6)H(5)O-H) - DH degrees (o-CH(3)C(6)H(4)O-H) = 8.1 +/- 4.0 kJ.mol(-1), DH degrees (C(6)H(5)O-H) - DH degrees (m-CH(3)C(6)H(4)O-H) = 0.9 +/- 3.4 kJ.mol(-1), and DH degrees (C(6)H(5)O-H) - DH degrees (p-CH(3)C(6)H(4)O-H) = 5.9 +/- 4.5 kJ.mol(-1). Based on the differences in Gibbs energies of formation obtained from the enthalpic data mentioned above and from published or calculated entropy values, it is concluded that the relative stability of the cresols varies according to p-cresol < m-cresol < o-cresol, and that of the radicals follows the trend m-methylphenoxyl < p-methylphenoxyl < o-methylphenoxyl. It is also found that these tendencies are enthalpically controlled.
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Affiliation(s)
- Laurence S Richard
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1649-016 Lisboa, Portugal
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Pinto SS, Diogo HP, Guedes RC, Costa Cabral BJ, Minas da Piedade ME, Martinho Simões JA. Energetics of hydroxybenzoic acids and of the corresponding carboxyphenoxyl radicals. Intramolecular hydrogen bonding in 2-hydroxybenzoic acid. J Phys Chem A 2007; 109:9700-8. [PMID: 16866422 DOI: 10.1021/jp054220g] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The energetics of the phenolic O-H bond in the three hydroxybenzoic acid isomers and of the intramolecular hydrogen O-H- - -O-C bond in 2-hydroxybenzoic acid, 2-OHBA, were investigated by using a combination of experimental and theoretical methods. The standard molar enthalpies of formation of monoclinic 3- and 4-hydroxybenzoic acids, at 298.15 K, were determined as Delta(f)(3-OHBA, cr) = -593.9 +/- 2.0 kJ x mol(-1) and Delta(f)(4-OHBA, cr) = -597.2 +/- 1.4 kJ x mol(-1), by combustion calorimetry. Calvet drop-sublimation calorimetric measurements on monoclinic samples of 2-, 3-, and 4-OHBA, led to the following enthalpy of sublimation values at 298.15 K: Delta(sub)(2-OHBA) = 94.4 +/- 0.4 kJ x mol(-1), Delta(sub)(3-OHBA) = 118.3 +/- 1.1 kJ x mol(-1), and Delta(sub)(4-OHBA) = 117.0 +/- 0.5 kJ x mol(-1). From the obtained Delta(f)(cr) and Delta(sub) values and the previously reported enthalpy of formation of monoclinic 2-OHBA (-591.7 +/- 1.3 kJ x mol(-1)), it was possible to derive Delta(f)(2-OHBA, g) = -497.3 +/- 1.4 kJ x mol(-1), Delta(f)(3-OHBA, g) = -475.6 +/- 2.3 kJ x mol(-1), and Delta(f)(4-OHBA, cr) = -480.2 +/- 1.5 kJ x mol(-1). These values, together with the enthalpies of isodesmic and isogyric gas-phase reactions predicted by density functional theory (B3PW91/aug-cc-pVDZ, MPW1PW91/aug-cc-pVDZ, and MPW1PW91/aug-cc-pVTZ) and the CBS-QMPW1 methods, were used to derive the enthalpies of formation of the gaseous 2-, 3-, and 4-carboxyphenoxyl radicals as (2-HOOCC(6)H(4)O(*), g) = -322.5 +/- 3.0 kJ.mol(-1) Delta(f)(3-HOOCC(6)H(4)O(*), g) = -310.0 +/- 3.0 kJ x mol(-1), and Delta(f)(4-HOOCC(6)H(4)O(*), g) = -318.2 +/- 3.0 kJ x mol(-1). The O-H bond dissociation enthalpies in 2-OHBA, 3-OHBA, and 4-OHBA were 392.8 +/- 3.3, 383.6 +/- 3.8, and 380.0 +/- 3.4 kJ x mol(-1), respectively. Finally, by using the ortho-para method, it was found that the H- - -O intramolecular hydrogen bond in the 2-carboxyphenoxyl radical is 25.7 kJ x mol(-1), which is ca. 6-9 kJ x mol(-1) above the one estimated in its parent (2-OHBA), viz. 20.2 kJ x mol(-1) (theoretical) or 17.1 +/- 2.1 kJ x mol(-1) (experimental).
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Affiliation(s)
- Susana S Pinto
- Centro de Química Estrutural, Complexo Interdisciplinar, Instituto Superior Técnico, 1049-001 Lisboa, Portugal
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Abstract
Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS) experiments showed that when aprotic ionic liquids vaporize under pressure and temperature conditions similar to those of a reduced-pressure distillation, the gas phase is composed of discrete anion-cation pairs. The evolution of the mass spectrometric signals recorded during fractional distillations of binary ionic liquid mixtures allowed us to monitor the changes of the gas-phase composition and the relative volatility of the components. In addition, we have studied a protic ionic liquid, and demonstrated that it exists as separated neutral molecules in the gas phase.
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Affiliation(s)
- João P Leal
- Departamento de Química, Instituto Tecnológico e Nuclear, 2686-953 Sacavém, Portugal
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Bernardes CES, Minas da Piedade ME, Amaral LMPF, Ferreira AIMCL, Ribeiro da Silva MAV, Diogo HP, Costa Cabral BJ. Energetics of C-F, C-Cl, C-Br, and C-I bonds in 2-haloethanols. enthalpies of formation of XCH(2)CH(2)OH (X = F, Cl, Br, I) compounds and of the 2-hydroxyethyl radical. J Phys Chem A 2007; 111:1713-20. [PMID: 17288411 DOI: 10.1021/jp0675678] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The energetics of the C-F, C-Cl, C-Br, and C-I bonds in 2-haloethanols was investigated by using a combination of experimental and theoretical methods. The standard molar enthalpies of formation of 2-chloro-, 2-bromo-, and 2-iodoethanol, at 298.15 K, were determined as Delta(f)H(degree)m(CH2CH2OH, l) = -315.5 +/- 0.7 kJ.mol-1, Delta(f)H(degree)mBrCH2CH2OH, l) = -275.8 +/- 0.6 kJ.mol-1, Delta(f)H(degree)m(ICH2CH2OH, l) = -207.3 +/- 0.7 kJ.mol-1, by rotating-bomb combustion calorimetry. The corresponding standard molar enthalpies of vaporization, Delta(vap)H(degree)m(ClCH2CH2OH) = 48.32 +/- 0.37 kJ.mol-1, Delta(vap)H(degree)m(BrCH2CH2OH) = 54.08 +/- 0.40 kJ.mol-1, and Delta(vap)H(degree)m(ICH2CH2OH) = 57.03 +/- 0.20 kJ.mol-1 were also obtained by Calvet-drop microcalorimetry. The condensed phase and vaporization enthalpy data lead to Delta(f)H(degree)m(ClCH2CH2OH, g) = -267.2 +/- 0.8 kJ.mol-1, Delta(f)H(degree)m(BrCH2CH2OH, g) = -221.7 +/- 0.7 kJ.mol-1, and Delta(f)H(degree)m(ICH2CH2OH, g) = -150.3 +/- 0.7 kJ.mol-1. These values, together with the enthalpy of selected isodesmic and isogyric gas-phase reactions predicted by density functional theory (B3LYP/cc-pVTZ) and CBS-QB3 calculations were used to derive the enthalpies of formation of gaseous 2-fluoroethanol, Delta(f)H(degree)m(FCH2CH2OH, g) = -423.6 +/- 5.0 kJ.mol-1, and of the 2-hydroxyethyl radical, Delta(f)H(degree)m(CH2CH2OH, g) = -28.7 +/- 8.0 kJ.mol-1. The obtained thermochemical data led to the following carbon-halogen bond dissociation enthalpies: DHo(X-CH2CH2OH) = 474.4 +/- 9.4 kJ.mol-1 (X = F), 359.9 +/- 8.0 kJ.mol-1 (X = Cl), 305.0 +/- 8.0 kJ.mol-1 (X = Br), 228.7 +/- 8.1 kJ.mol-1 (X = I). These values were compared with the corresponding C-X bond dissociation enthalpies in XCH2COOH, XCH3, XC2H5, XCH=CH2, and XC6H5. In view of this comparison the computational methods mentioned above were also used to obtain Delta(f)H(degree)m-594.0 +/- 5.0 kJ.mol-1 from which DHo(F-CH2COOH) = 435.4 +/- 5.4 kJ.mol-1. The order DHo(C-F) > DHo(C-Cl) > DHo(C-Br) > DHo(C-I) is observed for the haloalcohols and all other RX compounds. It is finally concluded that the major qualitative trends exhibited by the C-X bond dissociation enthalpies for the series of compounds studied in this work can be predicted by Pauling's electrostatic-covalent model.
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Affiliation(s)
- Carlos E S Bernardes
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1649-016 Lisbon, Portugal
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Abstract
A new all-atom force field, for the molecular modeling of metallocenes was constructed. Quantum chemical calculations were performed to obtain several force field terms not yet defined in the literature. The remainder were transferred from the OPLS-AA/AMBER framework. The parametrization work included the obtention of geometrical parameters, torsion energy profiles, and distributions of atomic charges that blend smoothly with the OPLS-AA specification for a variety of organic molecular fragments. Validation was carried out by comparing simulated and experimental data for five different ferrocene derivatives in the crystalline phase. The present model can be regarded as a step toward a general force field for metallocenes, built in a systematic way, easily integrated with OPLS-AA, and transferable between different metal-ligand combinations.
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Affiliation(s)
- José N Canongia Lopes
- Centro de Química Estrutural, Instituto Superior Técnico, 1049-001 Lisbon, Portugal.
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Mulder P, Mozenson O, Lin S, Bernardes CES, Minas da Piedade ME, Santos AFLOM, Ribeiro da Silva MAV, Dilabio GA, Korth HG, Ingold KU. Effect of Ring Substitution on the S−H Bond Dissociation Enthalpies of Thiophenols. An Experimental and Computational Study. J Phys Chem A 2006; 110:9949-58. [PMID: 16898699 DOI: 10.1021/jp062781h] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
There are conflicting reports on the origin of the effect of Y substituents on the S-H bond dissociation enthalpies (BDEs) in 4-Y-substituted thiophenols, 4-YC(6)H(4)S-H. The differences in S-H BDEs, [4-YC(6)H(4)S-H] - [C(6)H(5)S-H], are known as the total (de)stabilization enthalpies, TSEs, where TSE = RSE - MSE, i.e., the radical (de)stabilization enthalpy minus the molecule (de)stabilization enthalpy. The effects of 4-Y substituents on the S-H BDEs in thiophenols and on the S-C BDEs in phenyl thioethers are expected to be almost identical. Some S-C TSEs were therefore derived from the rates of homolyses of a few 4-Y-substituted phenyl benzyl sulfides, 4-YC(6)H(4)S-CH(2)C(6)H(5), in the hydrogen donor solvent 9,10-dihydroanthracene. These TSEs were found to be -3.6 +/- 0.5 (Y = NH(2)), -1.8 +/- 0.5 (CH(3)O), 0 (H), and 0.7 +/- 0.5 (CN) kcal mol(-1). The MSEs of 4-YC(6)H(4)SCH(2)C(6)H(5) have also been derived from the results of combustion calorimetry, Calvet-drop calorimetry, and computational chemistry (B3LYP/6-311+G(d,p)). The MSEs of these thioethers were -0.6 +/- 1.1 (NH(2)), -0.4 +/- 1.1 (CH(3)O), 0 (H), -0.3 +/- 1.3 (CN), and -0.8 +/- 1.5 (COCH(3)) kcal mol(-1). Although all the enthalpic data are rather small, it is concluded that the TSEs in 4-YC(6)H(4)SH are largely governed by the RSEs, a somewhat surprising conclusion in view of the experimental fact that the unpaired electron in C(6)H(5)S(*) is mainly localized on the S. The TSEs, RSEs, and MSEs have also been computed for a much larger series of 4-YC(6)H(4)SH and 4-YC(6)H(4)SCH(3) compounds by using a B3P86 methology and have further confirmed that the S-H/S-CH(3) TSEs are dominated by the RSEs. Good linear correlations were obtained for TSE = rho(+)sigma(p)(+)(Y), with rho(+) (kcal mol(-1)) = 3.5 (S-H) and 3.9 (S-CH(3)). It is also concluded that the SH substituent is a rather strong electron donor with a sigma(p)(+)(SH) of -0.60, and that the literature value of -0.03 is in error. In addition, the SH rotational barriers in 4-YC(6)H(4)SH have been computed and it has been found that for strong electron donating (ED) Ys, such as NH(2), the lowest energy conformer has the S-H bond oriented perpendicular to the aromatic ring plane. In this orientation the SH becomes an electron withdrawing (EW) group. Thus, although the OH group in phenols is always in-plane and ED irrespective of the nature of the 4-Y substituent, in thiophenols the SH switches from being an ED group with EW and weak ED 4-Ys, to being an EW group for strong ED 4-Ys.
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Affiliation(s)
- Peter Mulder
- Leiden Institute of Chemistry, Leiden University, P.O. Box 9502, 2300 RA Leiden, The Netherlands.
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Santos RC, Bernardes CES, Diogo HP, Piedade MFM, Canongia Lopes JN, Minas da Piedade ME. Energetics of the Thermal Dimerization of Acenaphthylene to Heptacyclene. J Phys Chem A 2006; 110:2299-307. [PMID: 16466268 DOI: 10.1021/jp056275o] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The energetics of the thermal dimerization of acenaphthylene to give Z- or E-heptacyclene was investigated. The standard molar enthalpy of the formation of monoclinic Z- and E-heptacyclene isomers at 298.15 K was determined as Delta(f)H(m)o (E-C24H16, cr) = 269.3 +/- 5.6 kJ x mol(-1) and Delta(f)H(m)o (Z-C24H16, cr) = 317.7 +/- 5.6 kJ x mol(-1), respectively, by microcombustion calorimetry. The corresponding enthalpies of sublimation, Delta(sub)H(m)o (E-C24H16) = (149.0 +/- 3.1) kJ x mol(-1) and Delta(sub)H(m)o (Z-C24H16) = (128.5 +/- 2.3) kJ x mol(-1) were also obtained by Knudsen effusion and Calvet-drop microcalorimetry methods, leading to Delta(f)H(m)o (E-C24H16, g) = (418.3 +/- 6.4) kJ x mol(-1) and Delta(f)H(m)o (Z-C24H16, g) = (446.2 +/- 6.1) kJ x mol(-1), respectively. These results, in conjunction with the reported enthalpies of formation of solid and gaseous acenaphthylene, and the entropies of acenaphthylene and both hepatcyclene isomers obtained by the B3LYP/6-31G(d,p) method led to the conclusion that at 298.15 K the thermal dimerization of acenaphthylene is considerably exothermic and exergonic in the solid and gaseous states (although more favorable when the E isomer is the product), suggesting that the nonobservation of the reaction under these conditions is of kinetic nature. A full determination of the molecular and crystal structure of the E dimer by X-ray diffraction is reported for the first time. Finally, molecular dynamics computer simulations on acenaphthylene and the heptacyclene solids were carried out and the results discussed in light of the corresponding structural and Delta(sub)H(m)o data experimentally obtained.
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Affiliation(s)
- Rui C Santos
- Centro de Química Estrutural, Complexo Interdisciplinar, Instituto Superior Técnico, 1049-001 Lisboa, Portugal
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Cruz FJAL, Lopes JNC, Calado JCG, Minas da Piedade ME. A Molecular Dynamics Study of the Thermodynamic Properties of Calcium Apatites. 1. Hexagonal Phases. J Phys Chem B 2005; 109:24473-9. [PMID: 16375450 DOI: 10.1021/jp054304p] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Structural and thermodynamic properties of crystal hexagonal calcium apatites, Ca10(PO4)6(X)2 (X = OH, F, Cl, Br), were investigated using an all-atom Born-Huggins-Mayer potential by a molecular dynamics technique. The accuracy of the model at room temperature and atmospheric pressure was checked against crystal structural data, with maximum deviations of ca. 4% for the haloapatites and 8% for hydroxyapatite. The standard molar lattice enthalpy, delta(lat)H298(o), of the apatites was calculated and compared with previously published experimental results, the agreement being better than 2%. The molar heat capacity at constant pressure, C(p,m), in the range 298-1298 K, was estimated from the plot of the molar enthalpy of the crystal as a function of temperature, H(m) = (H(m,298) - 298C(p,m)) + C(p,m)T, yielding C(p,m) = 694 +/- 68 J x mol(-1) x K(-1), C(p,m) = 646 +/- 26 J x mol(-1) x K(-1), C(p,m) = 530 +/- 34 J x mol(-1) x K(-1), and C(p,m) = 811 +/- 42 J x mol(-1) x K(-1) for hydroxy-, fluor-, chlor-, and bromapatite, respectively. High-pressure simulation runs, in the range 0.5-75 kbar, were performed in order to estimate the isothermal compressibility coefficient, kappaT, of those compounds. The deformation of the compressed solids is always elastically anisotropic, with BrAp exhibiting a markedly different behavior from those displayed by HOAp and ClAp. High-pressure p-V data were fitted to the Parsafar-Mason equation of state with an accuracy better than 1%.
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Affiliation(s)
- Fernando J A L Cruz
- Centro de Química Estrutural, Complexo Interdisciplinar, Instituto Superior Técnico, 1049-001 Lisboa, Portugal
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Estácio SG, Cabral do Couto P, Costa Cabral BJ, Minas da Piedade ME, Martinho Simões JA. Energetics of Intramolecular Hydrogen Bonding in Di-substituted Benzenes by the ortho−para Method. J Phys Chem A 2004. [DOI: 10.1021/jp0473422] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Sílvia G. Estácio
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal, and Grupo de Física Matemática da Universidade de Lisboa, Av. Professor Gama Pinto 2, 1649-003 Lisboa, Portugal
| | - P. Cabral do Couto
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal, and Grupo de Física Matemática da Universidade de Lisboa, Av. Professor Gama Pinto 2, 1649-003 Lisboa, Portugal
| | - Benedito J. Costa Cabral
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal, and Grupo de Física Matemática da Universidade de Lisboa, Av. Professor Gama Pinto 2, 1649-003 Lisboa, Portugal
| | - Manuel E. Minas da Piedade
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal, and Grupo de Física Matemática da Universidade de Lisboa, Av. Professor Gama Pinto 2, 1649-003 Lisboa, Portugal
| | - José A. Martinho Simões
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal, and Grupo de Física Matemática da Universidade de Lisboa, Av. Professor Gama Pinto 2, 1649-003 Lisboa, Portugal
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Abstract
The bonding energetics in a variety of alkaline metal, alkoxides and phenoxides, MOR, was investigated based on the corresponding enthalpies of formation in the crystalline state determined by reaction-solution calorimetry. The results obtained at 298.15 K were as follows: Delta(f)H(m)(o)(MOR, cr)/kJ mol(-1) = 382.7+/-1.4 (LiOC(6)H(5)), 513.6+/-2.5 (NaO-nC(6)H(13)), 326.4+/-1.4 (NaOC(6)H(5)), 375.2+/-3.4 (KOCH(3)), 434.5+/-2.7 (KOC(2)H(5)), 467.1+/-5.2 (KO-nC(3)H(7)), 459.3+/-2.1 (KO-nC(4)H(9)), 464.6+/-5.7 (KO-tC(4)H(9)), 464.3+/-2.5 (KO-nC(6)H(13)), 333.3+/-3.1 (KOC(6)H(5)), 380.6+/-2.9 (RbOCH(3)), 434.1+/-2.9 (RbOC(2)H(5)), 345.3+/-2.9 (LiOC(6)H(5)), 379.1+/-3.0 (CsOCH(3)), 432.3+/-3.1 (CsOC(2)H(5)), 466.9+/-5.0 (CsO-nC(3)H(7)), 461.3+/-3.5 (CsO-nC(4)H(9)), 461.9+/-2.5 (CsO-tC(4)H(9)), 349.2+/-1.4 (CsOC(6)H(5)). These results together with revised Delta(f)H(m)(o)(MOR, cr) values from the literature, were used to derive a consistent set of lattice energies for the MOR compounds and discuss general trends in the structure-energetics relationship based on the Kapustinskii equation.
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Affiliation(s)
- Paulo Nunes
- Centro de Química, Estrutural Complexo Interdisciplinar, Instituto Superior Técnico, 1049-001 Lisbon, Portugal
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Veiros LF, Minas da Piedade ME. On the transferability of IrI bond enthalpies between [Ir(μ-StBu)(I)2(CO)2]2 and trans-[Ir(X)(I)2(CO)(PPh3)2] (X=F, Cl, Br, I) complexes. J Organomet Chem 2002. [DOI: 10.1016/s0022-328x(02)01896-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Lagoa ALC, Diogo HP, Minas da Piedade ME, Schwarz K, Epple M. Driving Force for the Thermally Induced Solid State Polymerization of Alkali Metal Halogenoacetates: A Thermochemical Analysis. J Phys Chem B 2002. [DOI: 10.1021/jp014361s] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Lagoa ALC, Diogo HP, Minas da Piedade ME, Amaral LMPF, Guedes RC, Costa Cabral BJ, Kulikov DV, Verevkin SP, Siedler M, Epple M. Energetics of the C−Cl Bond in CH3CH(Cl)COOH. Enthalpy of Formation of (S)-(−)-2-Chloropropionic Acid and of the 1-Carboxyethyl Radical,. J Phys Chem A 2002. [DOI: 10.1021/jp020412p] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | | | | | - Luísa M. P. F. Amaral
- Centro de Investigação em Química, Departamento de Química, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre, 687, 4169-007 Porto, Portugal
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Dias AR, Dias PB, Diogo HP, Galvao AM, Minas da Piedade ME, Simoes JAM. Energetics of molybdenum-azobenzene, titanium-azobenzene, titanium-iodide, and titanium-carbonyl bonds in bis(cyclopentadienyl) complexes. Organometallics 2002. [DOI: 10.1021/om00150a011] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Diogo HP, De Alencar Simoni J, Minas da Piedade ME, Dias AR, Martinho Simoes JA. Thermochemistry of zirconium and niobium organometallic compounds. J Am Chem Soc 2002. [DOI: 10.1021/ja00060a026] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Calhorda MJ, Dias AR, Minas da Piedade ME, Salema MS, Simoes JAM. Studies on the transferability of transition-metal-carbon and -hydrogen bond enthalpies in bis(cyclopentadienyl) complexes. Organometallics 2002. [DOI: 10.1021/om00147a010] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Calhorda MJ, Carrondo MAAFDCT, Dias AR, Galvao AM, Garcia MH, Martins AM, Minas da Piedade ME, Pinheiro CI, Romao CC. Syntheses, electrochemistry, and bonding of bis(cyclopentadienyl)molybdenum alkyl complexes. Molecular structure of Mo(.eta.5-C5H5)2(C4H9)2. Thermochemistry of Mo(.eta.5-C5H5)2R2 and Mo(.eta.5-C5H5)2L (R = CH3, C2H5, C4H9; L = ethylene, diphenylacetylene). Organometallics 2002. [DOI: 10.1021/om00048a027] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Diogo HP, Dias AR, Dhalla A, Minas da Piedade ME, Begley TP. Mechanistic studies on DNA photolyase. 4. The enthalpy of cleavage of a model photodimer. J Org Chem 2002. [DOI: 10.1021/jo00026a029] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Diogo HP, Kiyobayashi T, Minas da Piedade ME, Burlak N, Rogers DW, McMasters D, Persy G, Wirz J, Liebman JF. The aromaticity of pyracylene: an experimental and computational study of the energetics of the hydrogenation of acenaphthylene and pyracylene. J Am Chem Soc 2002; 124:2065-72. [PMID: 11866622 DOI: 10.1021/ja012541+] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In this work, the aromaticity of pyracylene (2) was investigated from an energetic point of view. The standard enthalpy of hydrogenation of acenaphthylene (1) to acenaphthene (3) at 298.15 K was determined to be minus sign(114.5 +/- 4.2) kJ x mol(-1) in toluene solution and minus sign(107.9 +/- 4.2) kJ x mol(-1) in the gas phase, by combining results of combustion and reaction-solution calorimetry. A direct calorimetric measurement of the standard enthalpy of hydrogenation of pyracylene (2) to pyracene (4) in toluene at 298.15 K gave -(249.9 plus minus 4.6) kJ x mol(-1). The corresponding enthalpy of hydrogenation in the gas phase, computed from the Delta(f)H(o)m(cr) and DeltaH(o)m(sub) values obtained in this work for 2 and 4, was -(236.0 +/- 7.0) kJ x mol(-1). Molecular mechanics calculations (MM3) led to Delta(hyd)H(o)m(1,g) = -110.9 kJ x mol(-1) and Delta(hyd)H(o)m(2,g) = -249.3 kJ x mol(-1) at 298.15 K. Density functional theory calculations [B3LYP/6-311+G(3d,2p)//B3LYP/6-31G(d)] provided Delta(hyd)H(o)m(2,g) = -(244.6 +/- 8.9) kJ x mol(-1) at 298.15 K. The results are put in perspective with discussions concerning the "aromaticity" of pyracylene. It is concluded that, on energetic grounds, pyracylene is a borderline case in terms of aromaticity/antiaromaticity character.
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Affiliation(s)
- Hermínio P Diogo
- Centro de Química Estrutural, Complexo I, Instituto Superior Técnico, 1049-001 Lisboa, Portugal
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Siedler M, Kitchin SJ, Harris KDM, Lagoa ALC, Diogo HP, Minas da Piedade ME, Epple M. Porous poly(D,L-lactide) and poly(D,L-lactide-co-glycolide) produced by thermal salt elimination from halogenocarboxylatesElectronic supplementary information (ESI) available: detailed results of the combustion calorimetric experiments. See http://www.rsc.org/suppdata/dt/b1/b104979h/. ACTA ACUST UNITED AC 2001. [DOI: 10.1039/b104979h] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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