874 research outputs found
Plasticity of plant development in apricot as determined by genome and surrounding light. Iacona C, Cirilli M, Silvestri C, Pistelli L., Muleo R
No full textsee pd
The Italian journal of geosciences is increasing its appeal among geoscientists
No full textThis is an Editorial of the new Editorial Board of the Italian Journal of Geosciences, composed by Marco Balini (Milan), Hugo Bucher (Zürich), Simonetta Cirilli (Perugia), Laura Crispini (Genoa), Maurizio Mazzucchelli (Modena), and Giulio Ottonello (Genoa), which underlines the progress in the appeal of the journal among Geoscientists
Using genome plasticity to generate in Vitro Rootstocks Tolerant Waterlogging in Vivo. Muleo R, Iacona C, Pistelli L., Cirilli M, Silvestri C
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Crystal structure of (S)-3-(1-methylethyl)-5-[(1-naphthalenyloxy)methyl]-2-oxazolidinone, C17H19NO3
No full textThe title compd. is monoclinic, space group P21, a 8.269(9), b 6.215(9), c 14.816(8) Å, β 91.85(6)°, Z = 2, R = 0.044, Rw = 0.119 for 1213 reflections for I > 2σ. At. coordinates are given. ts structure has been solved by direct methods and refined to R=4.88% for all observed reflections.
Its overall structure is composed by a naphthyloxy and oxazolidin rings linked by a rotatable methylenic group. These rings are disposed in an almost orthogonal way because their least squared planes give a dihedral angle of 87.39(0.11)\%
Panoramic overview of unconventional approaches to detect chiral information
No full textThe concept of inherent chirality has gained considerable attention due to the possible synthesis of π-conjugated monomers that can be employed for preparing chiral electrode surfaces after electrooligomerization [1]. These materials have been used in enantiorecognition measurements involving chiral analytes, resulting in high selectivity based on diastereomeric interactions between the deposited enantiopure antipode and the probes dissolved in solution. In this context the high enantioselectivity of such chiral surfaces was used in combination with the mechanical and electrical properties of polypyrrole (Ppy) films to develop three new straightforward read-outs for the absolute on-off recognition of enantiomers of a chiral probe in solution; i) electromechanical deformation (a) [2], ii) electrochemically induced light emission (b) [3] and iii) self-induced enantioselective trajectories (c) [4]. These new approaches allow to convert chiral information present at the molecular level into macroscopic actuation, light emission or controlled trajectories. Furthermore, such systems allow correlating the output signal with the concentration of the enantiomers present in solution, even in the case of mixtures containing different ratios of the molecular antipodes.
[1] Arnaboldi, S.; Benincori, T.; Cirilli, R.; Kutner, W.; Magni, M.; Mussini, P. R.; Noworyta, K.; Sannicolo,̀ F. Chem. Sci. 2015, 6, 1706− 1711.
[2] Arnaboldi, S.; Gupta, B.; Benincori, T.; Bonetti, G.; Cirilli, R.; Kuhn, A. Anal. Chem. 2020, 92, 10042−10047.
[3] Salinas, G.; Arnaboldi, S.; Bonetti, G.; Cirilli, R.; Benincori, T.; Kuhn, A. Chirality 2021, 33, 875-882.
[4] Arnaboldi, S.; Salinas, G.; Karajic, A.; Garrigue, P.; Benincori, T.; Cirilli, R.; Bichon, S.; Gounel, S.; Mano, N.; Kuhn, A. Nat. Chem. 2021, 13, 1241-1247.
Keywords: (inherent)chirality; bipolar electrochemistry, chiral actuator, chiral swimmers, light emitting diodes
This work has been funded by the European Research Council (ERC) under the HORIZON-ERC-2021 program (grant agreement no 101040798, ERC Starting Grant CHEIR)
Approach to inherently chiralionic liquids
No full textIonic Liquids (ILs) constitute a class of solvents which got an increasing importance in the last ten years on account of some peculiar properties (low vapor pressure, chemical and thermal stability, solvating ability, non-flammability). Chiral ionic liquids (CILs) are used as solvents in asymmetric synthesis and in stereoselective polymerization, as chiral phases for gas chromatography, as chiral shift reagents in NMR spectroscopy and, in some cases, as promoters of cholesteric liquid crystals. Most of known CILs, are onium salts bearing chiral substituents characterized by one or several stereocenters. The research is focused to the design, synthesis, characterizetion and test in electrochemical oxo-reduction processes of a new family of CILs in which the stereogenic element (a stereogenic axis) coincides with the function responsible for the IL properties. Using the successful strategy recently employed for designing “inherently chiral” oligotiophenes,1 some “inherently chiral” CILs have been prepared based on bis-imidazolium and bi-piridinium atropisomeric scaffolds. The general structures and some specific examples are reported in the following scheme. The synthetic accessibility, the chromatographic behaviour of the precursors and the configurational stability of the new compounds is discussed.
This work is supported by Fondazione Cariplo (reg. No 2011-1851) and C.N.R.
(PM.P03.002.002).
1 Sannicolò, F.; Arnaboldi, S.; Benincori, T.; Bonometti, V.; Cirilli, R.; Dunsch, L.;
Kutner, W.; Longhi, G.; Mussini, P.R.; Panigati, M.; Pierini, M.; Rizzo, S. Angew.
Chem. Int. Ed. 2014, 53, 2623
Spin selectivity properties displayed by chiral electrode surfaces under an external magnetic field
No full textThe combination of spintronics with magneto- electrochemistry, particularly involving truly chiral molecular spin selectors, was promoted by the discovery of the Chiral Induced Spin Selectivity (CISS) effect by Ron Naaman and coworkers, observing spin polarization in photo-ejected electrons transmitted through a thin layer of enantiopure material adsorbed on gold, acting as an electron spin filter [1].
In this frame we present an innovative set-up which includes i) a non-ferromagnetic electrode (ITO) modified with a thin electroactive chiral film (the spin filter), ii) achiral redox couples dissolved in aqueous or organic solutions and iii) an external permanent magnet which was placed near the chiral film, considering as spin filters four different types of chiral selectors (with different stereogenic elements, i.e. helix, stereogenic axis and chiral pendant). [2,3,4]
A spectacular unforeseen effect was observed by means of cyclovoltammetry (CV), in fact CV peaks recorded in the presence of achiral redox couples reveal an impressive potential shift by flipping the magnet orientation (north vs south). This effect was also specular by changing the spin injector configuration.
The importance of these studies includes possible applications in the field of spintronics, electronics, chemical sensoristic and so on and provides a striking evidence of the spin selectivity properties of chiral thin films.
References:
[1] O. B Dor, S. Yochelis, S. P. Mathew, R. Naaman, Y. Paltiel, Nat. Commun. 4 (2013), 3256.
[2] T. Benincori, S. Arnaboldi, M. Magni, S. Grecchi, R. Cirilli, C. Fontanesi, P. R. Mussini, Chem. Sci., DOI: 10.1039/C8SC04126A (2019).
[3] S. Arnaboldi, S. Cauteruccio, S. Grecchi, T. Benincori, M. Marcaccio, A. Orbelli Biroli, G. Longhi, E. Licandro P. R. Mussini, Chem. Sci., 10 (2019) 1539-1548.
[4] S. Arnaboldi, T. Benincori, A. Penoni, L. Vaghi, R. Cirilli, S. Abbate, G. Longhi, G. Mazzeo, S. Grecchi, M. Panigati, P. R. Mussini, Chem. Sci., DOI: 10.1039/C8SC04862B (2019)
Unconventional Electrochemical Approaches for the Direct Readout of Chiral Information
No full textAmong the different strategies to endow conducting polymers with chiral features, the concept of inherent chirality is extremely attractive and efficient for several reasons. [1] Inherent chirality is an intrinsic propriety of the whole molecule in which the stereogenic element responsible for chirality coincides with the functional group responsible for the specific properties of the molecular material. The racemization barrier of these molecules is high enough to allow the separation into stable enantiomers by chiral HPLC. Their electro-oligomerization results in chiral electrode surfaces able to discriminate the antipodes of chiral species by differences in peak potential recorded by voltammetry. [2] This is a true advantage from an analytical point of view, because it is possible to achieve the enantioselective discrimination in racemic mixtures of the analyte, in contrast to most of the approaches presented in literature for which the recognition is only based on differences in current intensity. In this context the high enantioselectivity of such chiral surfaces was used to develop i) a new approach based on bipolar electrochemistry for the absolute on-off recognition of enantiomers of a chiral probe, [3] and ii) new autonomous enzymes based swimmers able to convert chiral information present at the molecular level into macroscopic enantioselective trajectories. [4]
[1] Arnaboldi, S.; Magni, M.; Mussini, P. R. Curr. Opin. Electrochem. 2018, 8, 60−72.
[2] Arnaboldi, S.; Benincori, T.; Cirilli, R.; Kutner, W.; Magni, M.; Mussini, P. R.; Noworyta, K.; Sannicolo,̀ F. Chem. Sci. 2015, 6, 1706− 1711.
[3] Arnaboldi, S.; Gupta, B.; Benincori, T.; Bonetti, G.; Cirilli, R.; Kuhn, A. Anal. Chem. 2020, 92, 10042−10047.
[4] Arnaboldi, S.; Salinas, G.; Karajic, A.; Garrigue, P.; Benincori, T.; Cirilli, R.; Bichon, S.; Gounel, S.; Mano, N.; Kuhn, A. Nat. Chem. 2021, in pres
Stazione mareografica di Trieste - Porto Lido : dati 2018
No full textAnalisi dei dati orari del livello del mare e dei dati medi ed estremi giornalieri del livello del mare rilevati alla stazione mareografica di Trieste - Porto Lido durante il 2018
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