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The ring-closing metathesis (RCM) of diethyl diallylmalonate in glycerol micellar conditions was studied using microwave irradiation. The micellization of different cationic surfactants in glycerol was first investigated. The results show the superiority of micellar catalysis in glycerol for a RCM reaction compared to glycerol alone, limiting byproduct formation. In comparison with the classical solution syntheses, the method here described allows safer reaction conditions, less hazardous chemical syntheses, and use of renewable feedstocks. The practical workup, separation, and purification operations minimize the use of materials.

The syntheses of ten novel mono-, di-or tri-cationic poly(ethylene glycol)-based ionic liquids (IL PEG s), incorporating tetra-substituted ammonium cations, are described. The poly(ethylene glycol) chains could be bridged or not and bore the cation. In the di-cationic IL PEG family, hydrophobic poly(methylene) or amphipathic poly(oxyethylene) spacers, with various lengths, were designed to connect the polar heads, while in the tri-cationic IL PEG family, the spacer was constituted by substituted diamines. The thermophysical properties such as viscosity or thermal stability were also investigated.Ionic liquids (IL) 1,2 and poly(ethylene glycol)s (PEG) 3-5 have attracted tremendous interest within the last decades in various applications. They are different from usual organic solvents, considering their intrinsic chemical and physical properties. They have good stability (thermal, chemical, redox, radiochemical), low or null vapour pressure, high thermal and ionic conductivity suitable for microwave assisted heating, 6,7 the possibility of recycling, and the ability to act as efficient solvents (also for gaseous reagents) and/or supports for reagent and catalyst immobilization. Among the diversity of functionalized ionic liquids, those incorporating poly(ethylene glycol) moieties (IL PEG ) into either cationic or anionic units, making the link between the two distinct but very similar fluids, 4,8-12 sharing common properties as those ones illustrated so far, yield a new appealing group of solvents finding applications across a range of disciplines including science, technology and engineering. 8 Despite the plethora of possible applications for the IL PEG systems, only a limited number of examples were reported on their use as solvents for organic synthesis and catalysis. 9 Different from PEGs or ionic liquids, PEG-based ionic liquids have been scarcely investigated and often neglected in recent literature.We have recently reported on the use of alkylammonium monocationic [mPEG 350 NMe 2 ][Br] 1 and di-cationic [(mPEG 350 NMe 2 ) 2 -CH 2 CH 2 ][Br] 3 as useful solvents for the synthesis of dipeptides under microwave irradiation 13 (Fig. 1). We report herein the preparation of a novel family of poly(ethylene glycol)-based ionic liquids 2 and 4-12, having up to three ammonium groups in their structure (Fig. 1). Their physicochemical properties were also investigated in the perspective of using these new solvents as additives in organic synthesis and catalysis. Indeed, slight changes in the dimethylether-PEG chain (mPEG-cation) structure along with the chemical nature of the counter anion, with long functional mPEG derivatized cations, might have a significant effect on the thermophysical and viscosity properties of IL PEG s and ionic liquids in general. 8,9 The poly(ethylene glycol) (PEG) chains bridged (e.g. IL PEG s 5 and 6) or not (e.g. IL PEG s 1-4 and 7-12) are on the cationic part of the molecule (Fig. 1). In the case of the di-cationic IL PEG s 3-6, the tetra-alkylammonium cations are interconnected by a hydro...