Match!

Kinetics and Energetics of Thermal Cis-Trans Isomerization of a Resonance-Activated Azobenzene in BMIM-Based Ionic Liquids for PF6−/Tf2N− Comparison

Published on Jul 29, 2017in Molecules3.06
· DOI :10.3390/molecules22081273
Guido Angelini14
Estimated H-index: 14
,
Cristina Campestre13
Estimated H-index: 13
+ 1 AuthorsCarla Gasbarri12
Estimated H-index: 12
Cite
Abstract
BMIM PF6 (1-butyl-3-methylimidazolium hexafluorophosphate) and BMIM Tf2N (1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide) are two conventional room-temperature ionic liquids widely employed and investigated as reaction media. Despite the presence of the same imidazolium ring in their structure they are different in many chemical and physical properties due to the nature of the anions. The thermal cis-trans isomerization of an electronically activated azobenzene have been used as reaction model to compare the behavior of PF6− and Tf2N−. Rotation is the mechanism by which the investigated azobenzene is converted into the trans isomer spontaneously in the dark both in BMIM PF6 and in BMIM Tf2N. The kinetic rate constants of the process have been determined at different temperatures and the activation energies of the reaction have been calculated according to the Arrhenius and Eyring equations. The results presented herein highlight different solute-solvent interactions involving the PF6− and Tf2N− anions during the cis-trans isomerization.
  • References (43)
  • Citations (4)
Cite
References43
Newest
Published on May 1, 2017in Tetrahedron2.38
Guido Angelini14
Estimated H-index: 14
,
Carla Gasbarri12
Estimated H-index: 12
Abstract The UV–vis spectra of α-nitrocyclohexanone were determined at 25 °C in a series of solvents, including room-temperature ionic liquids, water and CH 3 CN/CHCl 3 binary mixtures. A multiple linear regression analysis was performed by applying the Catalan empirical multiparameter solvent approach. Polarizability plays the major role in the solute-solvent interactions, as demonstrated by the quantification of the single solvent contributions, while an excellent linear correlation was found ...
Published on Apr 1, 2017in Journal of Molecular Liquids4.56
Dalal M. AL-Aqmar3
Estimated H-index: 3
(Ibb University),
H.I. Abdelkader3
Estimated H-index: 3
(Mansoura University),
Maram T.H. Abou Kana7
Estimated H-index: 7
(Cairo University)
Abstract Room temperature ionic liquids (RTILs) have emerged as nature-friendly media suitable for various applications. In this work, Optical absorption, fluorescence behavior and fluorescence lifetime of three rigorously purified imidazolium ionic liquids, 1-butyl-3-methylimidazolium chloride ( BMIM Cl ), 1-Butyl-3-methylimidazolium tetrachloroaluminate ( BMIM AlCl 4 ), 1-Butyl-3-methylimidazolium tetrafluoro-borate ( BMIM BF 4 ) are studied in the neat condition and with two types of laser dy...
Published on Mar 1, 2017in Journal of Molecular Liquids4.56
Carla Gasbarri12
Estimated H-index: 12
,
Guido Angelini14
Estimated H-index: 14
Abstract The Catalan and Spange empirical solvent parameters scales were applied to the solvatochromism of azobenzene and para -monosubstitued derivatives in a series of solvents. The experimental solvent-dependent wavenumbers of the maximum adsorption band (ν max ) were spectrophotometrically determined at 25 °C and compared to the values calculated by multiple linear regression analysis. The results show that polarizability (SP) is the dominant parameter over dipolarity (SdP), solvent acidity ...
Published on Jan 11, 2016in Chemistry: A European Journal5.16
Carla Gasbarri12
Estimated H-index: 12
,
F. Croce46
Estimated H-index: 46
+ 4 AuthorsGuido Angelini14
Estimated H-index: 14
Dispersions of single-walled carbon nanotubes (SWNTs) have been prepared by using the room-temperature ionic liquid [BMIM][BF4 ] (1-butyl-3-methylimidazolium tetrafluoroborate), the triblock copolymer Pluronic L121 [poly(ethylene oxide)5 -poly(propylene oxide)68 -poly(ethylene oxide)5 ] and the non-ionic surfactant Triton X-100 (TX100) in the pure state. The size of the SWNTs aggregates and the dispersion degree in the three viscous systems depend on the sonication time, as highlighted by UV/Vis...
Published on Aug 7, 2015in Journal of Organic Chemistry4.75
Guido Angelini14
Estimated H-index: 14
,
Nadia Canilho8
Estimated H-index: 8
+ 2 AuthorsCarla Gasbarri12
Estimated H-index: 12
The effects of a para substituent, as the electron-donating −OCH3 and −OtBu groups and the electron-withdrawing −Br and −F atoms, on azobenzene isomerization have been investigated in a series of imidazolium ionic liquids (BMIM PF6, BMIM BF4, BMIM Tf2N, EMIM Tf2N, BM2IM Tf2N, and HMIM Tf2N). The thermal cis–trans conversion tends to be improved in the presence of the substituent, as pointed out by the first-order rate constants measured at 25 °C. Both the rotation and the inversion mechanisms oc...
Published on Apr 13, 2015in Molecular Simulation1.78
Daniel Santos15
Estimated H-index: 15
(University of Porto),
M. Natália D. S. Cordeiro32
Estimated H-index: 32
(University of Porto)
The effect of replacing bis(trifluoromethylsulphonyl)imide ([NTf2]) by hexafluorophosphate ([PF6]) in room temperature ionic liquid (IL) 1-butyl-3-methylimidazolium bis(trifluoromethylsulphonyl)imide ([BMIm][NTf2]) confined between two gold interfaces is herein reported through molecular dynamics simulations using all-atom non-polarisable force-fields. Five systems were studied ranging from pure [BMIm][NTf2] to pure [BMIm][PF6], with [PF6] molar fractions of 0, 0.125, 0.25, 0.375 and 0.5. Specia...
Published on Nov 1, 2014in Chemical Physics Letters1.90
Muhammad Alif Mohammad Latif5
Estimated H-index: 5
(UPM: Universiti Putra Malaysia),
Nuno M. Micaelo11
Estimated H-index: 11
(University of Minho),
Mohd Basyaruddin Abdul Rahman21
Estimated H-index: 21
(UPM: Universiti Putra Malaysia)
Stochastic molecular dynamics simulations were performed to investigate the solvation free energy of 15 neutral amino acid side chain analogues in aqueous and five, 1-butyl-3-methylimidazolium ([BMIM])-based ionic liquids. The results in aqueous were found highly correlated with previous experimental and simulation data. Meanwhile, [BMIM]-based RTILs showed better solvation thermodynamics than water to an extent that they were capable of solvating molecules immiscible in water. Non-polar analogu...
Published on Feb 20, 2014in Journal of Physical Chemistry B2.92
Neeraj Kumar Joshi2
Estimated H-index: 2
,
Masanori Fuyuki4
Estimated H-index: 4
,
Akihide Wada16
Estimated H-index: 16
Spectral and kinetic behavior of thermal cis-to-trans isomerization of 4-aminoazobenzene (AAB) is examined in various solvents of different polarities. In contrast to azobenzene (AB), it is found the rate of thermal isomerization of AAB is highly dependent on solvent polarity. Accelerated rates are observed in polar solvents as compared to nonpolar solvents. Moreover, a decrease in the barrier height with an increase in medium polarity is observed. Our observations suggest that inversion is the ...
Published on Feb 17, 2014in Chemistry: A European Journal5.16
Alexander Schade5
Estimated H-index: 5
(Chemnitz University of Technology),
Nicole Behme1
Estimated H-index: 1
(Chemnitz University of Technology),
Stefan Spange29
Estimated H-index: 29
(Chemnitz University of Technology)
The four empirical solvent polarity parameters according to the Catalan scale—solvent acidity (SA), solvent basicity (SB), solvent polarizability (SP), and solvent dipolarity (SdP)—of 64 ionic liquids (ILs) were determined by the solvatochromic method. The SA parameter was determined solely by using [FeII(1,10-phenanthroline)2(CN)2] (Fe), the SB parameter by using the pair of structurally comparable dyes 3-(4-amino-3-methylphenyl)-7-phenylbenzo[1,2-b:4,5-b′]difuran-2,6-dione (ABF) and 3-(4-N,N-d...
Cited By4
Newest
Published on Jun 1, 2019in Journal of Molecular Liquids4.56
Guido Angelini14
Estimated H-index: 14
,
Luca Scotti8
Estimated H-index: 8
+ 1 AuthorsCarla Gasbarri12
Estimated H-index: 12
Abstract The thermal cis-trans isomerization of azobenzene and 4‑methoxyazobenzene has been investigated in aqueous solution in the presence of electrochemically synthesized silver nanoparticles (AgNPs) in the concentration range 0.32–32 ppm. The samples in which the investigated molecules in trans state have been converted into the cis isomer by irradiation immediately after their addition to the AgNPs solution show different kinetic behavior: in the case of azobenzene the cis-trans isomerizati...
Published on May 17, 2019in Polymers
Domenico Pirone1
Estimated H-index: 1
,
Valentina Marturano5
Estimated H-index: 5
+ 4 AuthorsBartosz Tylkowski10
Estimated H-index: 10
The development of photo-responsive capsules to tune and control the sustained-release of encapsulated actives is a fascinating and challenging route to improve the performances and effectiveness of a wide range of delivery applications. In this work, we report the preparation of visible light-responsive capsules obtained via oil-in-water interfacial polycondensation between modified diacyl-chloride azobenzene moiety and diamine flexible spacer in the presence of cross-linkers with different str...
Published on Jan 1, 2019in Physical Chemistry Chemical Physics3.57
Patrick R. Huddleston6
Estimated H-index: 6
(NTU: Nottingham Trent University),
Victor Volkov8
Estimated H-index: 8
(NTU: Nottingham Trent University),
Carole C. Perry44
Estimated H-index: 44
(NTU: Nottingham Trent University)
Diversity of photo-switching structural elements open up new opportunities in the engineering of light driven reshaping of matter, in catalysis on-click including photodynamic cancer therapy, in light sensitive transport control and in data storage. Assisted with quantum calculations we explore the photo-physical properties of novel 3,3-azothiophene molecular systems, the synthesis of which we reported recently. In the considered azothiophenes, upon exposure to radiation at 365 nm and at 530 nm...
Guido Angelini14
Estimated H-index: 14
,
Carla Gasbarri12
Estimated H-index: 12
Abstract Background and purpose During over ten years of experience in teaching organic chemistry at the Department of Pharmacy we have tried to answer the following question: why do most students tend to take the exam one, two, or more years after the end of the course they have attended? Several reasons could justify this delay, but three seem to be the most common drawbacks for our students: a) time needed for the comprehension of the arguments; b) the number of mandatory exams to pass before...