Green Solvent for Synthesis and Catalysis

Green termination for Synthesis and CatalysisAdnan S/OAbdul QayyumTitleGreen Solvent for deductive reasoning and catalysis Room Temperature Ionic Liquids.AbstractThis proposal describes a research project to discount the bonce runninesss the substitute green, non-volatile solvent to harmful volatile innate solvent and chemical industries in the future. The ionic liquids, whose properties can be predicted before their synthesis. The already known properties enable to gain required result for antithetic applications. This has versatile the range of applications of Ionics liquids. The properties of I.Ls ar affected by a no. of factors such as lattice energy, electrostatic potential between cation and anion, arouses of ions, breakup between the charges, symmetry hydrophobicity. Currently scientists are massageing not only on synthesis of new ionic liquids but also elevating their applications in different fields including solar cells, lubricants, green natural solvents etc. Because of significant properties attributed to these new classes of compounds, which give birth been classified as new compounds only a decade ago, we started studies towards the synthesis of ionic liquids. We attempted to prepare different types of ionic liquids. i) Imidazole establish ionic liquids ii) Caffeine found ionic liquids.IntroductionThe term ionic liquid implies a material that is fluid at (or close to) ambient temperature, is colorless, has a low viscosity and is easily handled. (Sheldon)Room temperature ionic liquids are generally salts of organic cations, e.g. tetraalkylammonium, tetraalkylphosphonium, N-alkylpyridinium, 1,3-dialkylimidazolium and trialkylsulfoniumcations. (Sheldon)Most basic definition of a room temperature ionic liquid is a salt that has a melting token at or beside room temperature. (Handy)Organic salts with melting points below ambient or chemical reaction temperature. (Maio)Ionic liquid is a salt with a melting temperature below the turn p oint of water. (Wilkes)Ionic liquids are defined as molten salt composed entirely of ions without any neutral molecules and having low melting point (usually cC)The properties of the ionic liquids are mentioned below.Problem or NeedIn this knowledge era, science has changed our world by discovering new methods to be the beneficial for human creation but simultaneously it also pollutes our environment. Therefore these methods and chemicals have also become somehow harmful to the human beings. So this is how, these chemicals, which polluting our environment have become a problem for the common people. Organic solvents are widely used in the laboratory and industries, which are volatile and used in huge amounts, i.e. Solvents are the almost damaging chemicals. That is why, our research project is about finding some green alternative to the most damaging solvents. The new alternative solvent ordain be non-volatile, less toxic, biodegradable, air and moisture stable and economically viable to large scale process.Objectives and Expected SignificanceWe have prepared project to give alternative solution to above mention problems. After synthesizing the green non-volatile, non-toxic solvent, the pollution could be reduced to great extent. Not only this, ionic liquid may have a lot of benefits and may be used as in batteries, propellants, lubricant, storage media for toxic gases, performance additives in pigments and many more.Methodology6.1. Imidazole based ionic liquids.Room temperature ionic liquids are generally salts of organic cations, e.g. tetraalkylammonium, tetraalkylphosphonium, N-alkylpyridinium, 1, 3-dialkylimidazolium and trialkylsulfoniumcations. Imidazole has a unique property to stabilization a positive charge on nitrogen thats why we use it as a substrate. Two nitrogens in imidazole stabilize quaternary nitrogen charge therefore the weaker the charge so it form ionic liquid which is liquid in room temperature. General reaction of imidazole based ion ic liquid is6.2. Caffeine based ionic liquidsCaffeine has been chosen due analogy of its structure with imidazole. Since five membered-ring that is fused with a six membered ring possessing amide and imide moieties, must behave want imidazole which has extensively been used in the synthesis of ionic liquids. For this reaction, first we prepared alkyl caffenium halides by treated of caffeine with different alkyl halide (i.e. methyl iodide, ethyl iodide and hexyl bromide) and taken tetrahydrofuran as a solvent, alkyl caffenium halide is obtained as a white crystals. We also tried to prepared caffeine based ILs due to its equal analogy structure with imidazole. Caffeine is relatively less expensive and is easily useable in abundance. ILs become cheaper and its applications enhanced due to the use of caffeine.It is reported in literature that Nitrogen containing heterocyclic compounds are used to generate stable carbenes, which were then used to carry out different reactions. One of s uch reaction is benzoin condensation that may be carried out using carbenes.Properties of Ionic LiquidsThe properties of ionic liquid differ by the different combinations of cation and anion for particular applications. Some of the serious properties of ionic liquids are melting point, vapour pressure thermal stability, viscosity, high heat capacity. Due to these properties ionic liquids are widely applicable, as installn in sort 2.Melting PointIonic liquids are defined as molten salt composed entirely of ions without any neutral molecules and having low melting point (usually 100C). The chemical and structural composition of an ionic liquid (molten salt) depends upon its melting point. take downing of melting point is due to the low symmetry of cation and weak intermolecular bonding. By keeping the cation constant we can also use different anions which can affect the melting point. The melting point decreases with increase in the sizing of anion. 3Vapour Pressure and Thermal S tabilityIonic liquid have no measureable vapour pressure due to this property it can easily stranded from reaction mixture by distillation. The thermal stability of an ionic liquid is directly related to the strength of the heteroatom-carbon and heteroatom-hydrogen bonds. Ionic liquids formed from either protonation of amines or phosphanes show significantly restricted thermal stability. 3DensityThere is a linear relationship between the density and the N-alkyl range of a function of cation. The density decreased as the N-alkyl chain increased. 3ViscosityIonic liquids are generally more viscous then the classical organic solvents. Cation shows some effect on the viscosity of the ionic liquid. Lower viscosities tend to be a result of small side chains that have sufficient mobility. As side chain increases due to vander waal forces viscosity increases. Temperature is some other factor which affects the viscosity of ionic liquid. As temperature increases viscosity decreases. 3Solubi lity CharacteristicsBy changing the combination of cations and anions we can tune the solubility of ionic liquid. The solubility of ionic liquid can also depends upon the temperament of R group. By increasing the length of alkyl chain the hydrophobicity of the cation increases, as the result its water solubility decreases. 6Solvent PropertiesThe most common classification used to describe a solvent is polarity of that solvent. Ionic liquids are considered as polar solvent by nature because they can dissolve and stabilize dipolar or charged solutes. 3 They have tendency to dissolve many different many other materials such as organic, inorganic and organometallic materials. 1Table1 Comparison of ionic liquids with organic solvents. 5Scope of Ionic liquidsIonic liquids are attractive, useful, advanced solvents that are a sight of attention by the renowned chemists for its unique and distinct properties. Its tunable components provide a wide range of successful and desire products.Fig ure2.IL publications (on may 27, 2009) determined from the ISI Web of Science in the last cardinal years.This is the main reason it is getting huge importance in the field of chemistry now a days. No doubt the immense research work in the field of green chemistry has been an attractive sight for the last few years. 5By the passage of time many new cations and anions have been reported. The common cations and anions are given belowCommon AnionsBF4 B(CN)4 CH2CHBF3 CF3BF3 C2F5BF3 nC3H7BF3 nC4H9BF3 PF6 CF3CO2 CF3SO3 N(SO2CF3)2 N(COCF3)(SO2CF3) N(SO2F)2 N(CN)2C(CN)3 SCN SeCN CuCl2 AlCl4 OHCommon CationsTimelineAs soon as this project is funded, we import chemicals in first two months while start synthesizing with the available chemicals. Within a one year InshaAllah, we will complete synthesis about 50 ionic liquids and also check their applications.EvaluationThe evaluation will be conducted by PCSIR and HEJ Research institute. This evaluation will be done under the direction of Dr. Na sir-Uddin who has much experience as a professional chopine evaluator. He had also done the evaluation of several large-scale governmentally funded projects. All chemists already have the experience on this research topic. Every sample will be done under the supervision of Dr. Imran Ali Hashmi, Ph. D from German on synthetic chemistry.Reference Literature CitedA review of ionic liquids towards supercritical fluid applicationsSedaKeskin, DefneKayrak-Talay, UgurAkman, O nerHortacsuDepartment of Chemical Engineering, Bogazici University, Bebek 34342, Istanbul, TurkeyReceived 2 August 2006 received in revised form 8 May 2007 accepted 29 May 2007Green chemistry ionic liquid Useful reaction solvents (TCI)Physical Properties of Alcohol Based Deep Eutectic SolventsThesis submitted for the item of Doctor of Philosophy by Robert Christopher Harris, University of Leicester, 2008Paradigm Confirmed The First Use of ionic Liquids to Dramatically Influence the Outcome of Chemical ReactionsOrgan ic letters, 2004, Vol. 6, no.5, 707-710Review on the Chemical Stabilities of Ionic LiquidsSubbiahSowmiah, VenkatesanSrinivasadesikan, Ming-Chung Tseng and Yen-Ho Chu *Molecules 2009, 14, 3780-3813 doi 10.3390/molecules14093780Ionic liquids Innovative fluids for chemical processingAIChE Journal Volume 47, Issue 11, pages 23842389, November 2001Room-Temperature Ionic Liquids. Solvents for Synthesis and CatalysisChem. Rev. 1999, 99, 2071-2083ACTA UniversitatisOuluensis, Johanna Krkkinen dressing and characterization of some ionic liquids and their use in the dimerization reaction of 2-methylpropeneThe Design of Polymeric Ionic Liquids for the Preparation of Functional MaterialsJournal of Macromolecular Science R _, Part C Polymer Reviews, 49339360, 2009Ionic Liquids Current developments, potential and drawbacks for industrial applicationsLenzingerBerichte, 84 (2005) 71-85Recent developments of task-specific ionic liquids in organic synthesisGreen chemical science Letters and Reviews V ol. 4, No. 1, March 2011, 41_54Task-Specific Ionic LiquidsJames H. Davis, Jr. Chemistry Letters Vol.33, No.9 (2004)Wohler, F. Liebig. J. Ann. Pharm. 1832, 3, 249-282Lapworth, A. J. J. Chem. Soc. 1903, 83, 995-1005Van DenBerg, H. J. J. Mol. Cat. 1943, 51, 1-12Suzuki et al. J. Am. Chem. Soc. 2003, 125, 8432-8433Budget1 Page