cas 151200-14-5, 1-METHYLIMIDAZOLIUM TETRAFLUOROBORATE

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Cinchona-derived prolinamide in Br?nsted acidic ionic liquids: A novel and recyclable catalytic system for asymmetric aldol reaction
Cinchonine-derived prolinamide in Br?nsted acidic ionic liquids was utilized for the first time as a novel and recyclable catalytic system for the asymmetric direct aldol reaction of acetone with aromatic aldehydes. The effects of the Br?nsted acidity and amount of ionic liquid, co-solvents, catalyst amount, and reaction temperature on the catalytic activity and enantioselectivity were studied in detail. Good to high yields and ee values were achieved for the aldol reaction of various aromatic aldehydes with neat acetone in 1-methylimidazolium tetrafluoroborate ([Hmim]+BF4-) in the presence of 10 mol% of catalyst at room temperature. [Hmim]+BF4- was also identified as a Br?nsted acid additive for the reaction and beneficial to the enhancement of catalytic performance. Moreover, the enhanced interaction between prolinamide and acidic ionic liquid facilitated the recoverability and reusability of organocatalyst. The catalyst recycling experiments indicated that there was only a slight loss in activity and enantioselectivity after four runs.
Lou, Lan-Lan,Zhang, Jiong,Du, Huanling,Zhao, Bo,Li, Shanshan,Yu, Wenjun,Yu, Kai,Liu, Shuangxi
p. 109 - 114
(2016)
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Elucidation of ionic interactions in the protic ionic liquid solutions by isothermal titration calorimetry
The strong hydrogen-bonded network noted in protic ionic liquids (PILs) may lead to stronger interactions of the ionic entities of PILs with solvents (water, methanol, ethylene glycol, dimethylsulfoxide (DMSO), N,Na?2-dimethylformamide (DMF)) as compared with those of aprotic ionic liquids (APILs). The PILs used in this work are 1-methylimidazolium tetrafluoroborate, 2-methylpyridinium tetrafluoroborate, and N-methylpyrrolodinium tetrafluoroborate in comparison to 1-butyl-3- methylimidazolium tetrafluoroborate, which is classified as an APIL. In this work, the excess partial molar enthalpy, HEIL obtained from isothermal calorimetric titrations at 298.15 K is used to probe the nature of interactions of the PIL cations with solvent molecules against those present in APIL-solvent systems. This work also reports interesting flip-flopping in the thermal behavior of these PIL-solvent systems depending upon the structure of the cationic ring of a PIL. In some cases, these flip-flops are the specific fingerprints for specific PILs in a common solvent environment. The excess partial molar enthalpy at infinite dilution, HE,a??IL, of these PILs bears a critical dependence on the solvent properties. An analysis of relative apparent molar enthalpies, ?2L, of the PIL solutions by the ion interaction model of Pitzer yields important information on ionic interactions of these systems. ? 2014 American Chemical Society.
Rai, Gitanjali,Kumar, Anil
p. 4160 - 4168
(2014)
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Electrophilic chemistry of thia-PAHs: Stable carbocations (NMR and DFT), S-alkylated onium salts, model electrophilic substitutions (nitration and bromination), and mutagenicity assay
(Chemical Equation Presented) First examples of stable carbocations are reported from several classes of thia-PAHs with four fused rings, namely, benzo[b]naphtho[2,1-d]thiophene (1) and its 3-methoxy derivative (2), phenanthro[4,3-b]thiophene (3) and its 7-methoxy (4), 10-methoxy (5), and 9-methoxy (6) derivatives, phenanthro[3,4-b]thiophene (7) and its 7-methoxy (8) and 9-methoxy (9) derivatives, and 3-methoxybenzo[b]naphtha[1,2-d]thiophene (11). In several cases, the resulting carbocations were also studied by GIAO-DFT. Charge delocalization modes in the resulting carbocations were probed, A series of S-alkylated onium tetrafluoroborates, namely, 1Me+, 1Et+, 2Et+, and 7Me+ (from 1, 2, and 7), 10Me+ and 10Et+ (from benzo[b]naphtha[1,2-d]thiophene 10), 12Me+ and 12Et+ (from phenanthro[3,2-b][1]benzothiophene 12), 13Me+ (from 3-methoxyphenanthro[3,2-b]benzothiophene 13), 14Me+ (from phenanthro[4,3-b][1]-benzothiophene 14), and 15Me + (from 3-methoxyphenanthro[4,3-b][1]benzothiophene 15), were synthesized. PAH-sulfonium salts 1Me+, 1Et+, 10Me +, 10Et+, 12Me+, and 14Me+ proved to be efficient akylating agents toward model nitrogen nucleophile receptors (imidazole and azaindole). Facile transalkylation to model nucleophiles (including guanine) is also supported by favorable reaction energies computed by DFT. Ring opening energies in thia-PAH-epoxides from 1, 3, and 7 and charge delocalization modes in the resulting carbocations were also evaluated. The four-ring-fused thia-PAHs 1, 2, 3, 4, 5, 7, 8, and 11 are effectively nitrated under extremely mild conditions. Nitration regioselectivity corresponds closely to protonation under stable ion conditions. Bromination of 4 and 6 is also reported. Comparative mutagenicity assays (Ames test) were performed on 1 versus 1NO2, 5 versus 5NO2, and 11 versus 11NO2. Compound 5NO2 was found to be a potent direct acting mutagen.
Laali, Kenneth K.,Chun, Joong-Hyun,Okazaki, Takao,Kumar, Subodh,Borosky, Gabriela L.,Swartz, Carol
p. 8383 - 8393
(2007)
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Inhibition mediated stabilization effect of imidazolium based ionic liquids on alcohol dehydrogenase
Ionic liquids (ILs) have gained increasing attention as solvents in chemical and biotechnological applications. Since alcohol dehydrogenases are of prime interest in industrial field, the present study has been conducted to study the influence of imidazolium based ionic liquids on kinetics, structure and stability of the thermophilic Thermoanaerobacter brockii (TBADH) alcohol dehydrogenase. Our results exhibited that the ionic liquids could affect kinetic parameters and stability, but not the tertiary structure. Through the determination of inhibition profile, which revealed mixed inhibition, Ki (affinity of IL for the enzyme) and KI (affinity of IL for enzyme-substrate complex) values were calculated. Structural analysis using crystallographic data from protein data bank elucidated the structural details responsible for different responses of alcohol dehydrogenases toward ionic liquids. Finally, enhanced stability in [MIm][Cl] was discussed.
Dabirmanesh, Bahareh,Khajeh, Khosro,Ranjbar, Bijan,Ghazi, Farideh,Heydari, Akbar
p. 66 - 71
(2012)
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Experimental and theoretical studies on polar Diels-Alder reactions of 1-nitronaphathalene developed in ionic liquids
The reactions between 1-nitronaphthalene 1 and two nucleophilic dienes, Danishefskys diene 2 and 1-trimethylsilyloxy-1,3-butadiene 3, to yield phenanthrenols 7 and 8 developed in protic and aprotic ionic liquids (ILs) with an imidazolium cation base permit to conclude that the reactions occur in better experimental conditions than in molecular solvents. The yields obtained with protic ILs are better than those observed with aprotic ILs. In this sense, the higher yields obtained with aprotic ILs, (working at 60°C, 48 h) are comparable with the lower yields observed in protic ILs (60°C, 24 h). DFT calculations for the reaction of 1-nitronaphthalene 1 with diene 3, in the absence and in the presence of tetrafluoroborate of 1-metilimidazolium [HMIM][BF4] as protic ILs, indicate that this reaction is a domino process that comprises two consecutive processes: i) a polar Diels-Alder (P-DA) reaction between 1 and 3, and ii) an elimination of nitroso acid 5 to yield dihydrophenanthrene 11. Thermodynamic calculations indicate that while the first reaction is the rate-determining step of this domino process, the nitroso acid elimination is the driving force responsible for the formation of dihydrophenanthrene 11. Implicit and explicit solvent effects indicate that while the hydrogen bond formation between HMIM and one oxygen atom of the nitro groups favour the two reactions, implicit solvent effects modelled by PCM decelerate the P-DA reaction by a large solvation of reagents. Finally, DFT analysis of reagents offers an explanation of the catalytic role of protic ILs in these P-DA reactions.
Mancini, Pedro M. E.,Rosa, Claudia D. Della,Ormachea, Carla M.,Kneeteman, Maria N.,Domingo, Luis R.
p. 13825 - 13834
(2013)
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Mesophilic alcohol dehydrogenase behavior in imidazolium based ionic liquids
The use of ionic liquids to replace organic solvents in biocatalytic processes has recently gained much attention. Despite the wide applications of oxidoreductases, there are few reports of their catalyzed reaction in ionic liquid. We have investigated the influence of four water miscible ionic liquids on the activity, stability and structure of the mesophilic alcohol dehydrogenase from yeast. Upon changes in ionic liquids concentration, both activity and stability of the enzyme were affected. As the concentration of ionic liquids increased, Km increased while kcat decreased. Associated conformational changes caused by ILs (150 mM) were monitored using fluorescence technique. Finally, the effects of ILs cations and anions on the enzyme activity and stability in aqueous IL mixtures were discussed.
Dabirmanesh, Bahareh,Khajeh, Khosro,Akbari, Jafar,Falahati, Hanieh,Daneshjoo, Somayeh,Heydari, Akbar
p. 139 - 143
(2011)
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1-Methylimidazolium tetrafluoroborate [Hmim][BF4]: An efficient acidic ionic liquid catalyst for insertion of α-diazo compounds into the N-H bonds of amines
The reusable acidic ionic liquid, 1-methylimidazolium tetrafluoroborate [Hmim][BF4], was found to be an effective catalyst for the insertion of α-diazoacetate into the N-H bonds of amines. The corresponding products were obtained in good yields and short reaction times via a simple procedure. The catalyst could be recycled and reused without any noticeable decrease in its activity.
Akbari, Jafar,Ebrahimi, Ali,Heydari, Akbar
p. 5417 - 5419
(2014)
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Process for preparation of nitrogen-containing vegetable oil-based lubricant additive
Chemically-modified fatty acids are prepared by reacting epoxidized fatty acids, their esters or triglyceride oils with amines of cyclic or aromatic hydrocarbons. The fatty acid derivatives produced are of the formula: wherein R is an H, branched or straight chain alkyl or alkenyl group, aromatic-containing group, glycerol, or glyceride, R″ is a C3 to C29 aliphatic chain comprising one or more of the derivatized methylene groups of the formula: wherein R1 and R2 are independently selected from the group consisting of H, cyclic hydrocarbons, substituted cyclic hydrocarbons, and aryl groups, with the proviso that only one of said R1 and R2 may be H. These fatty acid derivatives have utility as antiwear/antifriction additives for industrial oils and automotive applications.
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(2014/09/30)

Synthesis, characterization, and evaluation of 10-undecenoic acid-based epithio derivatives as multifunctional additives
Novel epithio compounds from alkyl epoxy undecanoates (n-alkyl, C1, C4, and C6; isoalkyl, C3, C4, and C8) were synthesized using an ammonium thiocyanate in ionic liquid 1-methylimidazolium tetrafluoroborate/H2O (2:1) solvent system in 85-90% yields by gas chromatographic (GC) analysis. The synthesized products were characterized by 1H and 13C nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy (FTIR), gas chromatography, and GC mass spectral (GC-MS) analyses and evaluated for their antioxidant, extreme pressure (EP), and antiwear (AW) properties in three different base oils, namely, epoxy jatropha fatty acid n-butyl esters (EJB), di-2-ethylhexyl sebacate (DOS), and mineral oil (S-105). Among the synthesized products, n-butyl epithio undecanoate exhibited superior antioxidant property (229.2 °C) compared to butylated hydroxytoluene (BHT, 193.8 °C) in base oil DOS and comparable performance in EJB and S-105 base oils. All of the epithio derivatives exhibited significantly enhanced weld point for the base oils EJB and DOS at 2 wt % level and displayed moderate enhancement in S-105 base oil. Methyl epithio undecanoate at 0.6% concentration exhibited considerable improvement in the wear scar of DOS base oil. The synthesized epithio derivatives have potential as multifunctional additives in lubricant formulations.
Geethanjali, Gorla,Padmaja, Korlipara V.,Sammaiah, Arukali,Prasad, Rachapudi B. N.
p. 11505 - 11511
(2015/02/19)

Br?nsted acidic ionic liquids: Green, efficient and reusable catalyst for synthesis of fluorinated spiro [indole-thiazinones/thiazolidinones] as antihistamic agents
Br?nsted acidic ionic liquid containing nitrogen-based organic cations 1-methylimidazolium and 1-butyl-3-methylimidazolium and inorganic anions such as BF4-, PF6- and PTSA - used as catalysts and reaction medium for synthesis of fluorinated spiro[3H-indole-3,2′-tetrahydro-1,3-thiazine]-2,4′(1H)-diones (4a-f), fluorinated spiro[3H-indole-3,2′-thiazolidine]-2,4′ (1H)-diones (5a-f) in 90-97% yield by one-pot environmentally benign microwave induced technique. Synthesized compounds have been evaluated for their ability to inhibit the contractions induced by histamine on guinea pig ileum. The measurement of pA2 values suggested that the reported compounds showed H1-antagonism.
Arya, Kapil,Rawat, Diwan Singh,Dandia, Anshu,Sasai, Hiroaki
experimental part
p. 117 - 122
(2012/05/20)

Synthesis of an amine-oleate derivative using an ionic liquid catalyst
A facile (and environmentally friendly) reaction between epoxidized methyl oleate and aniline to produce an oleate-aniline adduct, without the formation of fatty amide, was discovered. This reaction was carried out neat, with a catalytic amount of an ionic liquid. No solvent was used, no byproducts were produced, and the ionic liquid could be recovered and recycled. The reaction products were fully characterized by NMR and GC-MS. 2009 American Chemical Society.
Atanu, Biswas,Sharma, Brajendra K.,Doll, Kenneth M.,Erhan, Sevim Z.,Wlllett And, Julious L.,Cheng
experimental part
p. 8136 - 8141
(2010/07/17)

METHOD FOR THE PRODUCTION OF ONIUM SALTS WITH TETRAFLUOROBORATE ANION HAVING A REDUCED HALIDE CONTENT
The invention relates to a method for producing onium salts with tetrafluoroborate anion by reacting an onium halide with an oxonium tetrafluoroborate, sulfonium tetrafluoroborate, or triphenylcarbonium tetrafluoroborate.
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(2008/06/13)

Diels-Alder reaction in protic ionic liquids
Protic imidazolium ionic liquids have been tested as reaction media in the Diels-Alder reaction between cyclopentadiene and two dienophiles (dimethyl maleate and methyl acrylate). Good conversions and endo/exo selectivities were achieved. The activation of the dienophile by hydrogen bonding with protic imidazolium ILs was demonstrated.
Janus, Ewa,Goc-Maciejewska, Izabela,?ozyński, Marek,Pernak, Juliusz
p. 4079 - 4083
(2007/10/03)

The phase behaviour of 1-alkyl-3-methylimidazolium tetrafluoroborates; ionic liquids and ionic liquid crystals
Air- and water-stable 1-alkyl-3-methylimidazolium tetrafluoroborate salts with the general formula [Cn-mim][BF4] (n = 0-18) have been prepared by metathesis from the corresponding chloride or bromide salts. The salts have been characterised by 1H NMR and IR spectroscopy, microanalysis, polarising optical microscopy and differential scanning calorimetry. Those with short alkyl chains (n = 2-10) are isotropic ionic liquids at room temperature and exhibit a wide liquid range, whereas the longer chain analogues are low melting mesomorphic crystalline solids which display an enantiotropic smectic A mesophase. The thermal range of the mesophase increases with increasing chain length and in the case of the longest chain salt prepared, [C18-mim][BF4], the mesophase range is ca. 150°C.
Holbrey, John D.,Seddon, Kenneth R.
p. 2133 - 2139
(2007/10/03)