01633nas a2200157 4500008004100000022001400041245011200055210006900167260007100236300001200307490000800319520097800327100002601305700001601331856012801347 2010 eng d a1520-610600aContrasting thermosolvatochromic trends in pyridinium-, pyrrolidinium-, and phosphonium-based ionic liquids0 aContrasting thermosolvatochromic trends in pyridinium pyrrolidin a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcJAN a376-3810 v1143 a

Thermosolvatochromism has been studied in three series of ionic liquids, pyridinium-based 1-butylpyridinium, 1-hexylpyridinium, and 1-octylpyridinium with bis(trifluoromethylsulfonyl)imide [NTf2] and tetrafluoroborate [BF4] anions, pyrrolidinium-based ionic liquids 1-methyl-1-butylpyrrolidium, 1-methyl-1-hexylpyrrolidium, 1-methyl-1-octylpyrrolidium with bis(trifluoromethylsulfonyl) imide anion and phosphonium-based ionic liquids tetrabutylphosphonium with alanate and valinate anions. The effect of increase in alkyl chain length and temperature on normalized polarity E-T(N), Kanilet-Taft parameters, hydrogen bond donor ability (alpha), hydrogen bond acceptor ability (beta), and polarizability (pi*) was investigated in the temperature range of 298-353 K. Interestingly, the polarity decreases with temperature in the case of pyridinium- and pyrrolidinium-based ionic liquids, and it increases with temperature in the case of phosphonium-based ionic liquids.

1 aKhupse, Nageshwar, D.1 aKumar, Anil uhttps://library.ncl.res.in/content/contrasting-thermosolvatochromic-trends-pyridinium-pyrrolidinium-and-phosphonium-based-001751nas a2200157 4500008004100000022001400041245006100055210005900116260007100175300001600246490000800262520118600270100002601456700001601482856009501498 2011 eng d a1089-563900aCosolvent-directed diels-alder reaction in ionic liquids0 aCosolventdirected dielsalder reaction in ionic liquids a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcSEP a10211-102170 v1153 a

The rate constants of a bimolecular Diels-Alder reaction in binary mixtures of ionic liquids prepared in molecular solvents were analyzed to investigate the effect of viscosity of the medium and solvent effect. In this connection, we have carried out the Diels-Alder reaction of anthracene 9-carbinol with N-ethyl maleimide in binary mixtures of pyridinium-based ionic liquids, 1-butyl-pyridinium tetrafluoroborate, 1-buty1-3-pyridinium tetrafluoroborate, and 1-butyl-4-methyl pyridinium tetrafluoroborate in water, methanol, and chloroform at 298.15 K. The rates of reaction decreased, caused by gradually increasing the volume fraction of ionic liquids in solvents for all three ionic liquids. The kinetic results demonstrate a successful application of the pairwise interaction model built upon the concept of enforced hydrophobic hydration. A temperature-dependent study of kinetics of the Diels-Alder reaction was carried out in the binary mixtures of ionic liquids in water and was explained by the entropy-enthalpy compensation effect based upon activation parameters. Kinetics of the Diels-Alder reaction in highly aqueous medium was noted to be entropically driven.

1 aKhupse, Nageshwar, D.1 aKumar, Anil uhttps://library.ncl.res.in/content/cosolvent-directed-diels-alder-reaction-ionic-liquids-002007nas a2200229 4500008004100000022001400041245014800055210006900203260007500272300001400347490000700361520110400368653002501472653002101497653003101518653001401549653001801563100002201581700002601603700001601629856013201645 2016 eng d a1439-423500aComparative investigation of the ionicity of aprotic and protic ionic liquids in molecular solvents by using conductometry and NMR spectroscopy0 aComparative investigation of the ionicity of aprotic and protic  aPOSTFACH 101161, 69451 WEINHEIM, GERMANYbWILEY-V C H VERLAG GMBHcAPR a1006-10170 v173 a

Electrical conductivity (sigma), viscosity (), and self-diffusion coefficient (D) measurements of binary mixtures of aprotic and protic imidazolium-based ionic liquids with water, dimethyl sulfoxide, and ethylene glycol were measured from 293.15 to 323.15K. The temperature dependence study reveals typical Arrhenius behavior. The ionicities of aprotic ionic liquids were observed to be higher than those of protic ionic liquids in these solvents. The aprotic ionic liquid, 1-butyl-3-methylimidazolium tetrafluoroborate, [bmIm][BF4], displays 100% ionicity in both water and ethylene glycol. The protic ionic liquids in both water and ethylene glycol are classed as good ionic candidates, whereas in DMSO they are classed as having a poor ionic nature. The solvation dynamics of the ionic species of the ionic liquids are illustrated on the basis of the (HNMR)-H-1 chemical shifts of the ionic liquids. The self-diffusion coefficients D of the cation and anion of [HmIm][CH3COO] in D2O and in [D-6]DMSO are determined by using H-1 nuclei with pulsed field gradient spin-echo NMR spectroscopy.

10aconducting materials10aElectrochemistry10aelectrostatic interactions10aIon pairs10aionic liquids1 aThawarkar, Sachin1 aKhupse, Nageshwar, D.1 aKumar, Anil uhttps://library.ncl.res.in/content/comparative-investigation-ionicity-aprotic-and-protic-ionic-liquids-molecular-solvents-using