Room temperature ionic liquids organic synthesis

Room-temperature Ionic Liquids (RTIL) - Synthesis and Applications in Organic Synthesis under the Action of Microwaves... 

However, ionic liquids containing other classes of organic cations are known. Room-temperature ionic liquids containing organic cations including quaternary ammonium, phosphonium, pyridinium, and - in particular - imidazolium salts are currently available in combination with a variety of anions (Figure 3.1-1 provides some common examples) and have been studied for applications in electrochemistry [7, 8] and in synthesis [9-11]. 

The concept of performing microwave synthesis in room temperature ionic liquids (RTIL) as reaction media has been applied to several different organic transformations (Scheme 4.18), such as 1,3-dipolar cycloaddition reactions [54], catalytic transfer hydrogenations [55], ring-closing metathesis [56], the conversion of alcohols to alkyl halides [57, 58], and several others [59-61],... 

The Friedel-Crafts alkylation of aromatic compounds is of great importance in laboratory synthesis and industrial production. For example, the industrial processes for ethylbenzene, cumene and linear alkylbenzenes, etc., are on the base of this kind of reaction. It is well known that the drawbacks of the traditional acid catalysts such as A1Q3, H SO, and HF do great harm to the equipment and the environment, and these catalysts cannot be reused after the usual aqueous work-up besides, most of the reactions are carried out in the harmful and volatile organic solvents which can cause the environmental pollution aU of these problems need the replacement of the solvents or the acid catalysts. In this context, room-temperature ionic liquids have been iuCTeasingly employed as green solvents. 

Abstract The possible utilization of room temperature ionic liquids (RTILs), instead of volatile organic compounds (VOCs), in the electrochemical procedures of organic synthesis has been discussed. The synthesis of p-lactams, the activation of carbon dioxide and its utilization as renewable carbon source and the carbon-carbon bond formation reactions via umpolung of aldehydes (benzoin condensation and Stetter reaction) and via Henry reaction have been selected as typical electrochani-cal methodologies. The results, related to procedures performed in RTILs, have been compared with those performed in VOCs. The double role of RTILs, as green solvents and parents of electrogenerated reactive intermediates or catalysts, has been emphasized. 

Sotgiu G, Chiarotto I, Feroci M, Orsini M, Rossi L, Inesi A (2008) An electrochemical alternative strategy to the synthesis of P-lactams part 3. Room-temperature ionic liquids vs molecular organic solvents. Electrochim Acta 53 7852-7858... 

Chapter 16 outlines the possible utihzation of room-temperature ionic liquids (RTILs), instead of volatile organic compounds (VOCs), in the electrochemical procedures of organic synthesis of alpha- and beta-lactams. The activation of carbon dioxide and its utilization as a renewable carbon source is also highlighted. 

Room temperature ionic liquids (RTILs) are molten salts whose melting points are below room temperature. RTILs are formed when the constituent ions are sterically mismatched, thereby hindering crystal formation [17]. As polar solvents, RTILs have unique applications as tunable and environmentally benign solvents with very low volatility, high fire resistance, excellent chemical and thermal stability and wide liquid temperature range and electrochemical windows [17-19]. Solvent applications of RTILs include, for example, organic synthesis [17,20, 21], separations [22, 23], storage and transportation of hazardous chemicals [24], polymeric electrolytes [25, 26], dissolution of natural products [27] and synthesis of hollow metal oxide microspheres [28]. 

Although the information regarding room temperature ionic liquids (RTILs) as polymerisation solvents is extensive, there has been very little research published using RTILs as solvents for the synthesis of crosslinked polymers in general (Cooper 2004 Pavlova 2006) and molecularly imprinted polymers (MIPs) in particular (Booker et al 2006, 2007 Wang 2006, 2008 He 2008). Herein we examine a model system, cocaine, and will review the properties and performance of imprinted polymers prepared in volatile organic compounds (VOCs) with those prepared in RTILs, and the experimental parameters such as polymerisation temperature, solvent volume, rebinding conditions and template-RTIL combination, which may have a role to play in these systems. 

PSOS Polymer-supported organic synthesis r.t. Room temperature RTlLs Room-temperature ionic liquids TBAl Tetrabutylammonium iodide f-Bu t-butyl... 

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