Synthesis of Symmetrical Organic Carbonates via Significantly Enhanced Alkylation of Metal Carbonates with Alkyl Halides/Sulfonates in Ionic Liquid

Abstract

[reaction: see text] We report a new phosgene-free method for the synthesis of symmetrical organic carbonates via alkylation of metal carbonate with various alkyl halides and sulfonates in 1-n-butyl-3-methylimidazolium hexafluorophosphate, [bmim][PF6], as an ecofriendly reaction media. Alkylation of metal carbonate in various ionic liquids with 1-bromo-3-phenylpropane (1a) as a model reactant has thoroughly been investigated. Potassium and cesium carbonates appeared to be the most suitable metal carbonate due to their high solubility in ionic liquids. Besides good to excellent yields, this simple and convenient methodology is devoid of highly toxic and harmful chemicals such as phosgene and carbon monoxide, which is an additional advantage.

Synthesis of Linear and Cyclic Carbonates

“…Excellent yields may be obtained by running the reaction at 383 K in ionic liquids such as imidazolium salts, offering the advantage of simple experimental and work -up procedures [46] . An alternative route from CO 2 , alcohols and alkyl halides is also effective by the addition of a strong base (e.g., substituted guanidines), so as to trap the hydrogen chloride that is formed [47] .…”

Improvement of Hydrophobicity of Ionic Liquids by Partial Chlorination and Fluorination of the Cation

“…1 Nowadays, the applications of IL are rapidly increased. An amount of literature has reported the wide use of IL as extractant for liquid-liquid extraction, [2][3][4][5][6] solvent for organic synthesis, [7][8][9][10][11] catalyst for some reactions [12][13][14][15] and so on. The adjustable property of IL via combination of different cations or anions has attracted researchers' attention and thus plenty of new task-specific ILs were synthesized for particular applications.…”

Development of In Situ Electrochemical Scanning Electron Microscopy with Ionic Liquids as Electrolytes

“…After 1-ethyl-3-methylimidazolium tetrafluoroborate, the first air-and water-stable IL, was reported, [4] several ILs have been synthesized because of their many attractive features, such as negligible vapor pressure, noncombustibility, ionic conductivity and wide-ranging electrochemical potential. These characteristics have encouraged researchers to devise various applications, such as environmentally friendly solvents for chemical syntheses, [5][6][7][8][9][10][11][12] phase separations at lower critical temperatures, [13] new-type actuators, [14][15][16][17][18] non-volatile electrolytes for lithium ion batteries, [19][20][21][22][23][24] fuel cells, [25][26][27] and solar batteries. [28][29][30] It was recently reported that very slow vaporization of some ILs is detected under high vacuum and high temperature conditions.…”