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Juanes M, Usabiaga I, León I, Evangelisti L, Fernández JA, Lesarri A. The Six Isomers of the Cyclohexanol Dimer: A Delicate Test for Dispersion Models. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202005063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Melandri S, Evangelisti L, Canola S, Sa'adeh H, Calabrese C, Coreno M, Grazioli C, Prince KC, Negri F, Maris A. Chlorination and tautomerism: a computational and UPS/XPS study of 2-hydroxypyridine ⇌ 2-pyridone equilibrium. Phys Chem Chem Phys 2020; 22:13440-13455. [PMID: 32519689 DOI: 10.1039/d0cp02304c] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The prototropic tautomeric equilibrium in 2-hydroxypyridine serves as a prototype model for the study of nucleobases' behaviour. The position of such an equilibrium in parent and chlorine monosubstituted 2-hydroxypyridine compounds in the gas phase was determined using synchrotron based techniques. The lactim tautomer is dominant for the 5- and 6-substituted compounds, whereas the parent, 3- and 4-substituted isomers have comparable populations for both tautomers. Information was obtained by measuring valence band and core level photoemission spectra at the chlorine L-edge and carbon, nitrogen, and oxygen K-edges. The effect of chlorine on the core ionization potentials of the atoms in the heterocycle was evaluated and reasonable agreement with a simple model was obtained. Basic considerations of resonance structures correctly predicts the tautomeric equilibrium for the 5- and 6-substituted compounds. The vibrationally resolved structure of the low energy portion of the valence band photoionization spectra is assigned based on quantum-chemical calculations of the neutral and charged species followed by simulation of the vibronic structure. It is shown that the first ionization occurs from a π orbital of similar shape for both tautomers. In addition, the highly distinctive vibronic structure observed just above the first ionization of the lactim, for three of the five species investigated, is assigned to the second ionization of the lactam.
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Juanes M, Usabiaga I, León I, Evangelisti L, Fernández JA, Lesarri A. The Six Isomers of the Cyclohexanol Dimer: A Delicate Test for Dispersion Models. Angew Chem Int Ed Engl 2020; 59:14081-14085. [DOI: 10.1002/anie.202005063] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 05/11/2020] [Indexed: 11/06/2022]
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Silva WGDP, Evangelisti L, van Wijngaarden J. Internal Motions and Sulfur Hydrogen Bonding in Methyl 3-Mercaptopropionate. J Phys Chem A 2019; 123:9840-9849. [PMID: 31674188 DOI: 10.1021/acs.jpca.9b08681] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The effect of sulfur hydrogen bonding on the conformational equilibrium of methyl 3-mercaptopropionate was investigated using microwave spectroscopy in a supersonic jet expansion. The two most stable conformers (I and II) were assigned in the rotational spectra, and complex splitting patterns owing to the methyl internal rotation and SH tunneling motion were resolved and analyzed in detail. For both conformers, the experimental torsional barriers for the methyl top are similar and about 5.1 kJ mol-1, revealing that their geometrical differences do not affect the methyl internal rotation. The experimentally derived rotational and centrifugal distortion constants, along with the methyl internal rotation barriers, are discussed and compared with results from density functional theory and ab initio calculations. Quantum theory of atoms in molecules, noncovalent interactions, and natural bond orbital analyses show that the global minimum geometry (I), which has the thiol hydrogen oriented toward the carbonyl of the ester, is stabilized by an SH···O=C hydrogen bond. The presence of a hydrogen bond is confirmed by the derivation of an accurate experimental geometry that reveals a hydrogen bond distance and S-H-O angle of 2.515(4) Å and 117.4(1)°, respectively. These results are key benchmarks to expand the current knowledge of sulfur hydrogen bonds and the relationship between internal motions and conformational preferences in esters.
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Calabrese C, Li W, Prampolini G, Evangelisti L, Uriarte I, Cacelli I, Melandri S, Cocinero EJ. A General Treatment to Study Molecular Complexes Stabilized by Hydrogen‐, Halogen‐, and Carbon‐Bond Networks: Experiment and Theory of (CH
2
F
2
)
n
⋅⋅⋅(H
2
O)
m. Angew Chem Int Ed Engl 2019; 58:8437-8442. [DOI: 10.1002/anie.201902753] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Revised: 04/05/2019] [Indexed: 11/08/2022]
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Calabrese C, Li W, Prampolini G, Evangelisti L, Uriarte I, Cacelli I, Melandri S, Cocinero EJ. A General Treatment to Study Molecular Complexes Stabilized by Hydrogen‐, Halogen‐, and Carbon‐Bond Networks: Experiment and Theory of (CH
2
F
2
)
n
⋅⋅⋅(H
2
O)
m
. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201902753] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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32
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Neill JL, Yang Y, Muckle MT, Reynolds RL, Evangelisti L, Sonstrom RE, Pate BH, Gupton BF. Online Stereochemical Process Monitoring by Molecular Rotational Resonance Spectroscopy. Org Process Res Dev 2019. [DOI: 10.1021/acs.oprd.9b00089] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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Spada L, Evangelisti L, Li W, Orlacchio R, Caminati W. Carboxylic Acids, Reactivity with Alcohols and Clustering with Esters: A Rotational Study of Formic Acid-Isopropylformate. J Phys Chem A 2019; 123:1785-1789. [PMID: 30730139 DOI: 10.1021/acs.jpca.8b11294] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The rotational spectrum of the 1:1 complex formic acid-isopropylformate (FA-IPF) has been first observed when trying to assign the pulsed jet Fourier transform microwave (FTMW) spectrum of the adduct formic acid-2-propanol, by expanding a binary mixture of HCOOH and 2-propanol in He. The strong FTMW spectrum of isopropylformate, formed by the esterification reaction, was observed instead. However, when HCOOH was in excess in the binary mixture, it was possible to observe and assign the rotational spectrum of FA-IPF. Later on a much intense spectrum of FA-IPF was obtained, when combining FA with IPF. Finally, the spectra of five isotopologues of the most stable isomer of formic acid-isopropylformate have been observed by means of rotational spectroscopy in supersonic expansion. Some of them, HCOOH-(CH3)2CHOOCD and HCOOH-(CH3)2CDOOCH have been synthesized in the MW cavity by using DCOOH or (CH3)2CDOH as precursors in the esterification process. In the observed isomer of the complex, the two subunits are linked to each other by a standard O-H···O and a weak C-H···O hydrogen bond. The dissociation energy has been estimated to be 34.1 kJ·mol-1.
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Li W, Evangelisti L, Gou Q, Caminati W, Meyer R. The Barrier to Proton Transfer in the Dimer of Formic Acid: A Pure Rotational Study. Angew Chem Int Ed Engl 2019; 58:859-865. [DOI: 10.1002/anie.201812754] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2018] [Indexed: 11/07/2022]
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Juanes M, Li W, Spada L, Evangelisti L, Lesarri A, Caminati W. Internal dynamics of cyclohexanol and the cyclohexanol–water adduct. Phys Chem Chem Phys 2019; 21:3676-3682. [DOI: 10.1039/c8cp04455d] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Two for a tango: the rotational spectrum of a cyclohexanol–water dimer evidences a concerted motion of the water molecule and the hydroxyl group of the ring.
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Li W, Maris A, Calabrese C, Usabiaga I, Geppert WD, Evangelisti L, Melandri S. Atmospherically relevant acrolein–water complexes: spectroscopic evidence of aldehyde hydration and oxygen atom exchange. Phys Chem Chem Phys 2019; 21:23559-23566. [DOI: 10.1039/c9cp04910j] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Rotational spectroscopy and isotopic studies evidence oxygen exchange in water complexes of atmospherically important acrolein.
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37
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Evangelisti L, Caminati W. Modeling the internal rotation tunnelling in benzyl alcohol by ring fluorination: The rotational spectrum of 3,5-difluorobenzyl alcohol. Chem Phys Lett 2019. [DOI: 10.1016/j.cpletx.2018.100004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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38
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Spada L, Uriarte I, Li W, Evangelisti L, Cocinero EJ, Caminati W. Interactions between azines and alcohols: a rotational study of pyridine–tert-butyl alcohol. Phys Chem Chem Phys 2019; 21:3545-3549. [PMID: 30168540 DOI: 10.1039/c8cp04462g] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The observed spectrum identifies aCssymmetry σ-type complex, with the two subunits held together by coplanar “classical” O–H⋯N and weak C–H⋯π intermolecular hydrogen bonds. The O⋯N distance decreases by 4 mÅ upon deuteration of the hydroxyl group (reverse Ubbelohde effect).
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Li W, Evangelisti L, Gou Q, Caminati W, Meyer R. Barrier to Proton Transfer in the Dimer of Formic Acid: A Pure Rotational Study. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201812754] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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40
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Camici M, Evangelisti L, Balestri P, Cioni L, Fundi P, Sagripanti A, Meriggioli M, Giordani R. Coagulation Activation in Extracorporeal Hemodialysis. Int J Artif Organs 2018. [DOI: 10.1177/039139889702000307] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The Authors evaluated the behavior of protein C activity, factor X and factor VII coagulant activity and serum lipoprotein(a) before and after dialytic treatment in patients on maintenance hemodialysis. They observed depressed protein C activity that significantly (p<0.005) increased and became normal immediately after hemodialysis while factor X and factor VII increased (p<0.01; p<0.05) despite heparinization together with amount of serum lipoprotein(a). In vitro incubation (30 'at 37°C) of uremic and healthy blood showed a decrease in serum lipoprotein(a) concentration. After heparin addition (final concentration 0.5 U/ml) lipoprotein(a) increased in the uremic blood only. The clinical and physiopathological implications of these results are discussed.
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Li W, Spada L, Tasinato N, Rampino S, Evangelisti L, Gualandi A, Cozzi PG, Melandri S, Barone V, Puzzarini C. Theory Meets Experiment for Noncovalent Complexes: The Puzzling Case of Pnicogen Interactions. Angew Chem Int Ed Engl 2018; 57:13853-13857. [DOI: 10.1002/anie.201807751] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Revised: 08/20/2018] [Indexed: 01/29/2023]
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42
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Li W, Spada L, Tasinato N, Rampino S, Evangelisti L, Gualandi A, Cozzi PG, Melandri S, Barone V, Puzzarini C. Theory Meets Experiment for Noncovalent Complexes: The Puzzling Case of Pnicogen Interactions. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201807751] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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43
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Evangelisti L, Spada L, Li W, Federici I, Caminati W. The rotational spectrum of methyl trifluoroacetate. Mol Phys 2018. [DOI: 10.1080/00268976.2018.1451001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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44
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Calabrese C, Maris A, Evangelisti L, Piras A, Parravicini V, Melandri S. Rotational Spectrum and Conformational Analysis of N-Methyl-2-Aminoethanol: Insights into the Shape of Adrenergic Neurotransmitters. Front Chem 2018. [PMID: 29520356 PMCID: PMC5827360 DOI: 10.3389/fchem.2018.00025] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
We describe an experimental and quantum chemical study for the accurate determination of the conformational space of small molecular systems governed by intramolecular non-covalent interactions. The model systems investigated belong to the biological relevant aminoalcohol's family, and include 2-amino-1-phenylethanol, 2-methylamino-1-phenylethanol, noradrenaline, adrenaline 2-aminoethanol, and N-methyl-2-aminoethanol. For the latter molecule, the rotational spectrum in the 6–18 and 59.6–74.4 GHz ranges was recorded in the isolated conditions of a free jet expansion. Based on the analysis of the rotational spectra, two different conformational species and 11 isotopologues were observed and their spectroscopic constants, including 14N-nuclear hyperfine coupling constants and methyl internal rotation barriers, were determined. From the experimental data a structural determination was performed, which was also used to benchmark accurate quantum chemical calculations on the whole conformational space. Atom in molecules and non-covalent interactions theories allowed the characterization of the position of the intramolecular non-covalent interactions and the energies involved, highlighting the subtle balance responsible of the stabilization of all the molecular systems.
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Feyer V, Prince KC, Coreno M, Melandri S, Maris A, Evangelisti L, Caminati W, Giuliano BM, Kjaergaard HG, Carravetta V. Quantum Effects for a Proton in a Low-Barrier, Double-Well Potential: Core Level Photoemission Spectroscopy of Acetylacetone. J Phys Chem Lett 2018; 9:521-526. [PMID: 29314844 DOI: 10.1021/acs.jpclett.7b03175] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
We have performed core level photoemission spectroscopy of gaseous acetylacetone, its fully deuterated form, and two derivatives, benzoylacetone and dibenzoylmethane. These molecules show intramolecular hydrogen bonds, with a proton located in a double-well potential, whose barrier height is different for the three compounds. This has allowed us to examine the effect of the double-well potential on photoemission spectra. Two distinct O 1s core hole peaks are observed, previously assigned to two chemical states of oxygen. We provide an alternative assignment of the double-peak structure of O 1s spectra by taking full account of the extended nature of the wave function associated with the nuclear motion of the proton, the shape of the ground and final state potentials in which the proton is located, and the nonzero temperature of the samples. The peaks are explained in terms of an unusual Franck-Condon factor distribution.
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Evangelisti L, Brendel K, Mäder H, Caminati W, Melandri S. Rotational Spectroscopy Probes Water Flipping by Full Fluorination of Benzene. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201707155] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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47
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Evangelisti L, Brendel K, Mäder H, Caminati W, Melandri S. Rotational Spectroscopy Probes Water Flipping by Full Fluorination of Benzene. Angew Chem Int Ed Engl 2017; 56:13699-13703. [DOI: 10.1002/anie.201707155] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Indexed: 11/12/2022]
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48
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Gou Q, Favero LB, Feng G, Evangelisti L, Pérez C, Caminati W. Interactions between Ketones and Alcohols: Rotational Spectrum and Internal Dynamics of the Acetone-Ethanol Complex. Chemistry 2017; 23:11119-11125. [DOI: 10.1002/chem.201702090] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Indexed: 11/08/2022]
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49
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Evangelisti L, Spada L, Li W, Vazart F, Barone V, Caminati W. The Borderline between Reactivity and Pre-reactivity of Binary Mixtures of Gaseous Carboxylic Acids and Alcohols. Angew Chem Int Ed Engl 2017; 56:3872-3875. [PMID: 28252840 DOI: 10.1002/anie.201612231] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Revised: 01/16/2017] [Indexed: 01/10/2023]
Abstract
By mixing primary and secondary alcohols with carboxylic acids just before the supersonic expansion within pulsed Fourier transform microwave experiments, only the rotational spectrum of the ester was observed. However, when formic acid was mixed with tertiary alcohols, adducts were formed and their rotational spectra could be easily measured. Quantum mechanical calculations were performed to interpret the experimental evidence.
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50
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Evangelisti L, Spada L, Li W, Vazart F, Barone V, Caminati W. The Borderline between Reactivity and Pre-reactivity of Binary Mixtures of Gaseous Carboxylic Acids and Alcohols. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201612231] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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