The growing number of applications of ionic liquids (ILs) in industry have brought attention to the green credentials of synthesis, as well as their cyto-and ecotoxicities both for their use and accidental leakage into the environment. With the above in mind, we designed a class of ILs with either cations bearing gluconamide motif and aliphatic side chains or the anion incorporating gluconic acid (derived from food waste) moiety. An ionic liquid with imidazolium cation with an appended gluconic amide (bearing 5 hydroxyl groups) moiety was also synthesised for a useful comparison. Different structural features were considered, placing emphasis on the nature and length of the alkyl chain and the nature of the anion. For comparison, two ILs with one hydroxyl group and another without any hydroxyl-groups were prepared.

A new electrochemical procedure for the synthesis of organic carbamates from amines and carbon dioxide has been developed using selective cathodic reduction of carbon dioxide in CO2-saturated room-temperature ionic liquid BMIm-BF4 solutions containing amines 1a-j, followed by addition of EtI as an alkylating agent. The synthesis was carried out under mild (PCO2 = 1.0 atm, t = 55 degrees C) and safe conditions, and the use of volatile and toxic solvents and catalysts (according to the growing demand for ecofriendly synthetic methodologies), as well as of any supporting electrolyte (for a very easy workup of the reaction mixture), was avoided. Carbamates 2a-j were isolated in good to high yields.

Isopropenyl acetate was proved to be an efficient reagent for acetylation of amine in the absence of solvent and catalyst. The corresponding acetamides were obtained in very high yields without any purification.a IPA was isopropenyl acetate. b All reactions were carried out in vial at 60 °C for 3 h. c We used ethyl acetate as the acylation reagent. † Electronic supplementary information (ESI) available: Characterization data and copies of the 1 H and 13 C NMR spectra of all the crude reaction mixtures. See

A new carboxylating reagent ((-)CH(2)CN/CO(2)) was obtained by bubbling CO(2) in a CH(3)CN-TEAP (tetraethylammonium perchlorate) solution previously electrolyzed under galvanostatic control. Organic carbamates were isolated from these solutions after addition of amines and an alkylating agent. In this paper, we describe the optimized conditions for the electrochemical synthesis of carbamates from amines and CO(2), in mild and safe conditions, without any addition of bases, probases, or catalysts. Carbamates were isolated from primary and secondary aliphatic amines in high to excellent yields and from aromatic amines in moderate yields (dependent on the nucleophilicity of the nitrogen atom).

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The umpolung reaction of α,β-unsaturated aldehydes to saturated esters has been carried out in an ionic liquid by organocatalysis of electrogenerated NHC. The roles of solvent, precatalyst and proton donor of the ionic liquid have been verified and good to high yields of esters have been obtained using a "green" and mild methodology.

Ionic liquids (ILs) are considered in the majority of cases green solvents, due to their virtually null vapor pressure and to the easiness in recycling them. In particular, imidazolium ILs are widely used in many fields of Chemistry, as solvents or precursors of N-heterocyclic carbenes (NHCs). The latter are easily obtained by deprotonation of the C2-H, usually using strong bases or cathodic reduction. Nevertheless, it is known that weaker bases (e.g., triethylamine) are able to promote C2-H/D exchange. From this perspective, the possibility of deprotonating C2-H group of an imidazolium cation by means of a basic counter-ion was seriously considered and led to the synthesis of imidazolium ILs spontaneously containing NHCs. The most famous of this class of ILs are N,N'-disubstituted imidazolium acetates. Due to the particular reactivity of this kind of ILs, they were appointed as “organocatalytic ionic liquids” or “proto-carbenes.” Many papers report the use of these imidazolium acetates in organocatalytic reactions (i. e., catalyzed by NHC) or in stoichiometric NHC reactions (e.g., with elemental sulfur to yield the corresponding imidazole-2-thiones). Nevertheless, the actual presence of NHC in N,N'-disubstituted imidazolium acetate is still controversial. Moreover, theoretical studies seem to rule out the presence of NHC in such a polar environment as an IL. Aim of this Mini Review is to give the reader an up-to-date overview on the actual or potential presence of NHC in such an “organocatalytic ionic liquid,” both from the experimental and theoretical point of view, without the intent to be exhaustive on N,N'-disubstituted imidazolium acetate applications.

The electrochemical reduction of imidazolium‐based ionic liquids (BMIm‐X) leads to the formation of corresponding N‐heterocyclic carbenes (NHCs). Owing to the peculiar reactivity of NHCs, solutions containing NHC in ionic liquid (IL) can be used in CO2 capture or in organocatalyzed reactions. It is thus important to know the stability of the carbene in the parent IL. In fact, the NHC lifetime can be influenced by the nature of the anion (X−) of the IL. To better understand the relationship between NHC lifetime (and reactivity towards CO2) and IL medium, the presence of electrogenerated NHC in the parent IL is studied by using voltammetric, infrared, and thermogravimetric analyses and by isolation of the adduct between NHC and benzaldehyde. It is thus possible to estimate the actual NHC concentration and its lifetime through voltammetric peak‐current measurements. Moreover, NHC in BMIm‐X is able to catch CO2 (yielding the adduct NHC–CO2) and, triggered by heating (60‐150 °C), to release CO2. It is proven that the half‐life of NHC and the rate of CO2 capture are both affected by the nature of X−.