Synthesis of new pyrazolium based tunable aryl alkyl ionic liquids and their use in removal of methylene blue from aqueous solution

In this study, two new pyrazolium based tunable aryl alkyl ionic liquids, 2-ethyl-1-(4-methylphenyl)-3,5- dimethylpyrazolium tetrafluoroborate (3a) and 1-(4-methylphenyl)-2-pentyl-3,5-dimethylpyrazolium tetrafluoroborate (3b), were synthesized via three-step reaction and characterized. The removal of methylene blue (MB) from aqueous solution has been investigated using the synthesized salts as an extractant and methylene chloride as a solvent. The obtained results show that MB was extracted from aqueous solution with high extraction efficiency up to 87 % at room temperature at the natural pH of MB solution. The influence of the alkyl chain length on the properties of the salts and their extraction efficiency of MB was investigated

On the eigenvalues and eigenvectors of a lorentzian rotation matrix by using split quaternions

In this paper, we examine eigenvalue problem of a rotation matrix in Minkowski 3 space by using split quaternions. We express the eigenvalues and the eigenvectors of a rotation matrix in term of the coefficients of the corresponding unit timelike split quaternion. We give the characterizations of eigenvalues (complex or real) of a rotation matrix in Minkowski 3 space according to only first component of the corresponding quaternion. Moreover, we find that the casual characters of rotation axis depend only on first component of the corresponding quaternion. Finally, we give the way to generate an orthogonal basis for 31 by using eigenvectors of a rotation matrix.No sponso

Effects of para-substitution and alkyl chain length on the melting points of tunable aryl alkyl pyrazolium hexafluorophosphate ionic liquids

Ionic liquids (ILs) are low-melting organic salts that consist entirely of ions. During the last decade, they have found numerous applications because of their unique properties such as wide liquid range, nonflammability and negligible vapor pressure at ambient temperatures [1-3]. The properties of ILs can be tuned by changing the constituent ions. In recent years, unlike commonly known alkyl substituted ILs a new class of ILs called Tunable Aryl Alkyl Ionic Liquids (TAAILs) has drawn attention [4-6]. By replacing one of the two alkyl groups on the cation with an aryl ring, a wide range of possibilities to tune the properties of TAAILs is provided. In this study, eight new tunable aryl alkyl pyrazolium hexafluorophosphate ionic liquids were synthesized via three step reaction and characterized. The effects of para-substituted electronwithdrawing (-Br, -Cl) and electron-donating (-CH3, -OCH3) substituents and alkyl chain length (-Ethyl, or –Butyl) on the melting points of synthesized salts were investigated

Removal of methylene blue by new tunable aryl/alkyl ionic liquids/salts (TAAILs) from aqueous solution

The removal of methylene blue (MB) from aqueous solution has been investigated using new tunable 1-aryl-2-alkyl-3,5-dimethylpyrazolium hexafluorophosphate salts ([Ph(R)C(R?)pz][PF6], R: -Cl, -Br, -Me, -OMe, R?: -C2H5, or -C4H9) as an extractant and methylene chloride as a diluent. The influence of p-substituent and alkyl chain length on the removal efficiency of MB from aqueous solution was investigated. The obtained results show that MB was extracted from aqueous solution with high extraction efficiency up to 99.7 % in a very short time. The salt (4a) used for extraction of MB was recovered and reused for four runs

1-aryl-2-alkyl-3,5-dimethylpyrazolium based tunable aryl alkyl ionic liquids

Ionic liquids (ILs) are organic molten salts with melting points below 100 °C .Owing to their remarkable properties, they have been widely used for various applications as environmentally benign alternative to volatile organic solvents over the last decade [1,2]. In recent years the new generation of ILs called tunable aryl alkyl ionic liquids (TAAILs) has drawn attention for modifying the properties of ILs for specific applications [3,4]. Unlike commonly known alkyl substituted ILs the properties of TAAILs can be tuned with inductive, mesomeric and steric effects. In this study, tennew tunable aryl alkyl pyrazolium methanesulfonate ionic liquids were synthesized under microwave (MW) irradiation and characterized. Eight of the salts can be classed as room temperature ionic liquids (RTILs). The synthesizedionic liquids have a high thermal stability up to 284.93 °C. It was found that the electron-withdrawing (-NO2, -Cl, -Br ) substituents tend to higher melting points than the electron-donating (-Me, -OMe) substituents

Synthesis and characterization of new generation ionic liquids and their use as solvent and reagent

Bu çalışmada, aril-/alkil-3,5-dimetilpirazolyum metansülfonat [CH3SO3]-, tetrafloroborat [BF4]- ve heksaflorofosfat [PF6]- iyonik sıvıları sentezlendi ve yapıları aydınlatıldı. Bu iyonik sıvıların erime/camsı geçiş sıcaklıkları, termal kararlılıkları, elektrokimyasal pencere aralıkları, bilinen çözücülerdeki çözünürlükleri incelendi ve iletkenlikleri sıcaklığa bağlı olarak ölçüldü. Oda sıcaklığı iyonik sıvılarının viskozite, yoğunluk ve kırılma indisi değerleri sıcaklığa bağlı olarak ölçüldü. Fenil halkasındaki sübstitüent türünün, alkil zinciri uzunluğunun ve anyon türünün iyonik sıvıların özellikleri üzerine olan etkileri araştırıldı. 1-fenil-2-heksil-3,5-dimetilpirazolyum metansülfonat, 1-fenil-2-heksil-3,5-dimetilpirazolyum tetrafloroborat ve 1-fenil-2-heksil-3,5-dimetilpirazolyum heksaflorofosfat iyonik sıvıları benzil alkol'ün mikrodalga ışıma altında periyodik asit ile yükseltgenme tepkimelerinde çözücü olarak kullanıldı.In this study, aryl-/alkyl-3,5-dimethylpyrazolium methanesulfonate [CH3SO3]-, tetrafluoroborate [BF4]- and hexafluorophosphate [PF6]- ionic liquids were synthesized and their structures were determined. Their melting/glass transition temperatures, thermal stabilities, electrochemical windows, and solubility properties in common solvents were determined. Their conductivities were measured as a function of temperature. Densities, viscosities and refractive indices were also measured as a function of temperature for the room temperature ionic liquids. The effects of the type of the substituent on the phenyl ring, alkyl chain length and the type of the anion on the properties of ionic liquids were investigated. 1-phenyl-3,5-dimethyl-2-hexylpyrazolium methanesulfonate, 1-phenyl-3,5-dimethyl-2-hexylpyrazolium tetrafluoroborate and 1-phenyl-3,5-dimethyl-2-hexylpyrazolium hexafluorophosphate ionic liquids were used as solvents for the oxidation reactions of benzyl alcohol with periodic acid under microwave irradiatio

Quinaldinium Chlorochromate(VI), (QnCC) Catalyzed Oxidation of Alcohols with Periodic Acid Under Solvent-Free Conditions and Microwave Irradition

The economic synthesis of quinaldinium chlorochromate(VI), C10H9NH[CrO3Cl], (QnCC) was performed by using a 1:1:1 stoichiometric amounts of CrO3, HCl (aq) and quinaldine. QnCC was isolated in 99% yield as an orange crystalline solid and characterized with FT-IR, 1H-NMR, and 13C-NMR. An efficient, selective, and environmentally friendly oxidation of alcohols with 1.1 equiv. periodic acid (H5IO6) catalyzed by QnCC (2 mol%) is described. The primary and secondary alcohols were oxidized to their corresponding aldehydes and ketones under solvent-free conditions at room temperature and MW irradiation in high to excellent yields

Phenyl/alkyl-substituted-3,5-dimethylpyrazolium ionic liquids

The synthesis and characterization of a series of new phenyl/alkyl-substituted-3,5-dimethylpyrazolium ionic liquids ([Phpz(R)][X] R = CnH2n+1 n: 1,2,3,4,5,6,7 [X] = CH3SO3-, BF4-, PF6-) are described. Their melting points, thermal stabilities, electrochemical windows, and solubility properties in common solvents were investigated. They were found to exhibit very good electrochemical and thermal stabilities. The results indicate that these ionic liquids have a high thermal stability up to 374 degrees C and a large electrochemical window of 4.63 V. The thermophysical properties such as density, viscosity and refractive index were also measured as a function of temperature for the ionic liquids which are in liquid state at room temperature