Immaculada Dinarès - Academia.edu (original) (raw)
Papers by Immaculada Dinarès
European Journal of Organic Chemistry, 2005
Optimization studies allowed the efficient synthesis of a simple structural motif based on meta-b... more Optimization studies allowed the efficient synthesis of a simple structural motif based on meta-bis(1-imidazolyl)benzenes 1 through copper-catalyzed coupling of 1,3-diiodobenzene and imidazole under mild reaction conditions. This protocol was then used to prepare a representative sterically hindered N-arylimidazole 2a, the most common structural motif among N-heterocyclic carbenes (NHC). Having optimized the main variables governing Cu I-catalyzed imidazole N-arylation, the
Beilstein Journal of Organic Chemistry, 2011
The synthesis of multifunctional indenes with at least two different functional groups has not ye... more The synthesis of multifunctional indenes with at least two different functional groups has not yet been extensively explored. Among the plausible synthetic routes to 3,5-disubstituted indenes bearing two different functional groups, such as the [3-(aminoethyl)inden-5-yl)]amines, a reasonable pathway involves the (5-nitro-3-indenyl)acetamides as key intermediates. Although several multistep synthetic approaches can be applied to obtain these advanced intermediates, we describe herein their preparation by an aldol-type reaction between 5-nitroindan-1-ones and the lithium salt of N,N-disubstituted acetamides, followed immediately by dehydration with acid. This classical condensation process, which is neither simple nor trivial despite its apparent directness, permits an efficient entry to a variety of indene-based molecular modules, which could be adapted to a range of functionalized indanones.
Arkivoc, 2007
We report the first synthesis and relevant structural aspects of some simple examples of the beta... more We report the first synthesis and relevant structural aspects of some simple examples of the betaines 5-7 and their immediate precursors 8-10. Inner salts 5b, 6b and 7b were isolated, whereas compounds 5a, 6a and 7a were transformed to dihydropyridine derivatives. Their liquid-crystal behavior was examined and for benzimidazolyl pyridinium bromide 8a the secondorder hyperpolarizability (β) was measured.
Journal of The Chemical Society, Chemical Communications, 1986
Theoretical calculations have been carried out and experimental dipole moments measured for sever... more Theoretical calculations have been carried out and experimental dipole moments measured for several pyridinium azolate inner salts; depending on the substituent on the pyridinium ring the compounds are either planar, almost freely rotating molecules, or are hindered with the rings perpendicular to each other, and in all cases the dipole moments are very large (10-18 Debye).
Etude de derives de pyrazolures, triazole-1,2,4ures, tetrazolures et benzimidazolures substitues ... more Etude de derives de pyrazolures, triazole-1,2,4ures, tetrazolures et benzimidazolures substitues sur un carbone par triphenyl-2,4,6 pyridinio
Chemistry of Heterocyclic Compounds
Farmaco (Società chimica italiana : 1989), 1996
Farmaco (Società chimica italiana : 1989), 1989
The synthesis and the antiparasitic evaluation of twelve new 5-nitroimidaole derivatives has been... more The synthesis and the antiparasitic evaluation of twelve new 5-nitroimidaole derivatives has been carried out. The most effective compounds were the less hydrophilic pyridinium and imidazolium salts (IV), (V) and (X), and above all the tetrahydropyridine derivatives (XII) and (XIII).
Un conjunt de professors de les facultats de Química i Farmàcia de la Universitat de Barcelona he... more Un conjunt de professors de les facultats de Química i Farmàcia de la Universitat de Barcelona hem elaborat un material docent en suport electrònic, d'accés lliure a la xarxa, que descriu el procediment pràctic de diverses operacions bàsiques de treball al laboratori químic. L'objectiu principal és crear un material docent que serveixi de suport a l'aprenentatge dels estudiants i a
ChemInform, 1994
ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance t... more ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Arkivoc, 2013
The counteranion exchange of quaternary 1,2,3-triazolium salts was examined using a simple method... more The counteranion exchange of quaternary 1,2,3-triazolium salts was examined using a simple method that permitted halide ions to be swap for a variety of anions using an anion exchange resin (A¯ form). The method was applied to 1,2,3-triazolium-based ionic liquids and the iodideto-anion exchange proceeded in excellent to quantitative yields, concomitantly removing halide impurities. Additionally, an anion exchange resin (N 3¯ form) was used to obtain the benzyl azide from benzyl halide under mild reaction. Likewise, following a similar protocol, bis(azidomethyl)arenes were also synthesized in excellent yields. The results of a proton NMR spectroscopic study of simple azolium-based ion pairs are discussed, with attention focused on the significance of the charged-assisted (C-H) + •••anion hydrogen bonds of simple azolium systems such as 1-butyl-3-methylimidazolium and 1-benzyl-3-methyl-1,2,3-triazolium salts.
Electronic Journal of Theoretical Chemistry, 1997
Conformations of γ-lactones containing two hydroxyl groups are studied by the MM3/3JHH tandem met... more Conformations of γ-lactones containing two hydroxyl groups are studied by the MM3/3JHH tandem method. The computed coupling constants for the ring protons agree moderately well with the experimentally determined ones (rms = 1.37 Hz).
Topics in Heterocyclic Chemistry, 2010
ABSTRACT Abstract Imidazolium salts, which constitute a varied pool of charged chemical entities,... more ABSTRACT Abstract Imidazolium salts, which constitute a varied pool of charged chemical entities, are situated at the crossroads of multidisciplinary fields in chemistry because of their incorporation in a broad array of molecular systems. Imidazolium functionality has emerged as a privileged structural motif for the design of specifically tailored artificial receptors for anion recognition and sensing. The specific focus of this chapter is to give an overview of these positively charged systems, with a brief discussion of the chemistry of imidazolium quaternary salts. Representative examples of imidazolium-based systems have been ordered according to their molecular frameworks and include cyclophanes, protophanes, and calixarenes as well as a tripodal molecular platform. The final section concerns miscellaneous molecular systems with a variety of coexisting topologies as well as a number of subunits, each with its own specific properties. These systems have applications in anion recognition chemistry leaning toward nanoscience. Graphical Abstract
Tetrahedron Letters, 1988
ABSTRACT
ChemInform, 2002
Skip to Main Content. ... Reviews. ChemInform Abstract: The Facets of the Heterocyclic BetainePoo... more Skip to Main Content. ... Reviews. ChemInform Abstract: The Facets of the Heterocyclic BetainePool. Ermitas Alcalde,; Immaculada Dinares,; Neus Mesquida,; Lluisa Perez-Garcia. Article first published online: 22 MAY 2010. DOI: 10.1002/chin.200217276. ...
Organic & Biomolecular Chemistry, 2013
Revisiting a '3 +... more Revisiting a '3 + 1' convergent stepwise strategy permitted the synthesis of [1₄]imidazoliophane 2·2Br in excellent yield for a macrocyclization. The new [1₄]triazoliophane 3 and bis(1,2,3-triazolium) counterpart 4·2Cl were less synthetically accessible and the hybrid derivative 5·Cl proved troublesome to prepare. Triazolophane 3 was devoid of anion-binding affinities, while charged [1₄]heterophane prototypes showed a particular preference for acetate. When association constants were compared, dicationic systems 2·2PF6 and 4·2PF6 showed greater values than monocationic macrocycle 5·PF6, and the highest affinities corresponded to the bis(imidazolium) receptor 2·2PF6.
The Journal of Organic Chemistry, 1994
Page 1. J. Org. Chem. 1994,59, 639-643 639 Heterocyclic Betaines. 19.' Unconventional Ex... more Page 1. J. Org. Chem. 1994,59, 639-643 639 Heterocyclic Betaines. 19.' Unconventional Extended r-Systems Containing Pyridinium and Benzimidazolate Subunits. Synthesis and Characterization Ermitas Alcalde,' Immaculada ...
European Journal of Organic Chemistry, 2005
Optimization studies allowed the efficient synthesis of a simple structural motif based on meta-b... more Optimization studies allowed the efficient synthesis of a simple structural motif based on meta-bis(1-imidazolyl)benzenes 1 through copper-catalyzed coupling of 1,3-diiodobenzene and imidazole under mild reaction conditions. This protocol was then used to prepare a representative sterically hindered N-arylimidazole 2a, the most common structural motif among N-heterocyclic carbenes (NHC). Having optimized the main variables governing Cu I-catalyzed imidazole N-arylation, the
Beilstein Journal of Organic Chemistry, 2011
The synthesis of multifunctional indenes with at least two different functional groups has not ye... more The synthesis of multifunctional indenes with at least two different functional groups has not yet been extensively explored. Among the plausible synthetic routes to 3,5-disubstituted indenes bearing two different functional groups, such as the [3-(aminoethyl)inden-5-yl)]amines, a reasonable pathway involves the (5-nitro-3-indenyl)acetamides as key intermediates. Although several multistep synthetic approaches can be applied to obtain these advanced intermediates, we describe herein their preparation by an aldol-type reaction between 5-nitroindan-1-ones and the lithium salt of N,N-disubstituted acetamides, followed immediately by dehydration with acid. This classical condensation process, which is neither simple nor trivial despite its apparent directness, permits an efficient entry to a variety of indene-based molecular modules, which could be adapted to a range of functionalized indanones.
Arkivoc, 2007
We report the first synthesis and relevant structural aspects of some simple examples of the beta... more We report the first synthesis and relevant structural aspects of some simple examples of the betaines 5-7 and their immediate precursors 8-10. Inner salts 5b, 6b and 7b were isolated, whereas compounds 5a, 6a and 7a were transformed to dihydropyridine derivatives. Their liquid-crystal behavior was examined and for benzimidazolyl pyridinium bromide 8a the secondorder hyperpolarizability (β) was measured.
Journal of The Chemical Society, Chemical Communications, 1986
Theoretical calculations have been carried out and experimental dipole moments measured for sever... more Theoretical calculations have been carried out and experimental dipole moments measured for several pyridinium azolate inner salts; depending on the substituent on the pyridinium ring the compounds are either planar, almost freely rotating molecules, or are hindered with the rings perpendicular to each other, and in all cases the dipole moments are very large (10-18 Debye).
Etude de derives de pyrazolures, triazole-1,2,4ures, tetrazolures et benzimidazolures substitues ... more Etude de derives de pyrazolures, triazole-1,2,4ures, tetrazolures et benzimidazolures substitues sur un carbone par triphenyl-2,4,6 pyridinio
Chemistry of Heterocyclic Compounds
Farmaco (Società chimica italiana : 1989), 1996
Farmaco (Società chimica italiana : 1989), 1989
The synthesis and the antiparasitic evaluation of twelve new 5-nitroimidaole derivatives has been... more The synthesis and the antiparasitic evaluation of twelve new 5-nitroimidaole derivatives has been carried out. The most effective compounds were the less hydrophilic pyridinium and imidazolium salts (IV), (V) and (X), and above all the tetrahydropyridine derivatives (XII) and (XIII).
Un conjunt de professors de les facultats de Química i Farmàcia de la Universitat de Barcelona he... more Un conjunt de professors de les facultats de Química i Farmàcia de la Universitat de Barcelona hem elaborat un material docent en suport electrònic, d'accés lliure a la xarxa, que descriu el procediment pràctic de diverses operacions bàsiques de treball al laboratori químic. L'objectiu principal és crear un material docent que serveixi de suport a l'aprenentatge dels estudiants i a
ChemInform, 1994
ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance t... more ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Arkivoc, 2013
The counteranion exchange of quaternary 1,2,3-triazolium salts was examined using a simple method... more The counteranion exchange of quaternary 1,2,3-triazolium salts was examined using a simple method that permitted halide ions to be swap for a variety of anions using an anion exchange resin (A¯ form). The method was applied to 1,2,3-triazolium-based ionic liquids and the iodideto-anion exchange proceeded in excellent to quantitative yields, concomitantly removing halide impurities. Additionally, an anion exchange resin (N 3¯ form) was used to obtain the benzyl azide from benzyl halide under mild reaction. Likewise, following a similar protocol, bis(azidomethyl)arenes were also synthesized in excellent yields. The results of a proton NMR spectroscopic study of simple azolium-based ion pairs are discussed, with attention focused on the significance of the charged-assisted (C-H) + •••anion hydrogen bonds of simple azolium systems such as 1-butyl-3-methylimidazolium and 1-benzyl-3-methyl-1,2,3-triazolium salts.
Electronic Journal of Theoretical Chemistry, 1997
Conformations of γ-lactones containing two hydroxyl groups are studied by the MM3/3JHH tandem met... more Conformations of γ-lactones containing two hydroxyl groups are studied by the MM3/3JHH tandem method. The computed coupling constants for the ring protons agree moderately well with the experimentally determined ones (rms = 1.37 Hz).
Topics in Heterocyclic Chemistry, 2010
ABSTRACT Abstract Imidazolium salts, which constitute a varied pool of charged chemical entities,... more ABSTRACT Abstract Imidazolium salts, which constitute a varied pool of charged chemical entities, are situated at the crossroads of multidisciplinary fields in chemistry because of their incorporation in a broad array of molecular systems. Imidazolium functionality has emerged as a privileged structural motif for the design of specifically tailored artificial receptors for anion recognition and sensing. The specific focus of this chapter is to give an overview of these positively charged systems, with a brief discussion of the chemistry of imidazolium quaternary salts. Representative examples of imidazolium-based systems have been ordered according to their molecular frameworks and include cyclophanes, protophanes, and calixarenes as well as a tripodal molecular platform. The final section concerns miscellaneous molecular systems with a variety of coexisting topologies as well as a number of subunits, each with its own specific properties. These systems have applications in anion recognition chemistry leaning toward nanoscience. Graphical Abstract
Tetrahedron Letters, 1988
ABSTRACT
ChemInform, 2002
Skip to Main Content. ... Reviews. ChemInform Abstract: The Facets of the Heterocyclic BetainePoo... more Skip to Main Content. ... Reviews. ChemInform Abstract: The Facets of the Heterocyclic BetainePool. Ermitas Alcalde,; Immaculada Dinares,; Neus Mesquida,; Lluisa Perez-Garcia. Article first published online: 22 MAY 2010. DOI: 10.1002/chin.200217276. ...
Organic & Biomolecular Chemistry, 2013
Revisiting a '3 +... more Revisiting a '3 + 1' convergent stepwise strategy permitted the synthesis of [1₄]imidazoliophane 2·2Br in excellent yield for a macrocyclization. The new [1₄]triazoliophane 3 and bis(1,2,3-triazolium) counterpart 4·2Cl were less synthetically accessible and the hybrid derivative 5·Cl proved troublesome to prepare. Triazolophane 3 was devoid of anion-binding affinities, while charged [1₄]heterophane prototypes showed a particular preference for acetate. When association constants were compared, dicationic systems 2·2PF6 and 4·2PF6 showed greater values than monocationic macrocycle 5·PF6, and the highest affinities corresponded to the bis(imidazolium) receptor 2·2PF6.
The Journal of Organic Chemistry, 1994
Page 1. J. Org. Chem. 1994,59, 639-643 639 Heterocyclic Betaines. 19.' Unconventional Ex... more Page 1. J. Org. Chem. 1994,59, 639-643 639 Heterocyclic Betaines. 19.' Unconventional Extended r-Systems Containing Pyridinium and Benzimidazolate Subunits. Synthesis and Characterization Ermitas Alcalde,' Immaculada ...