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This work reports on the first solvate ionic liquids (SILs) based on aluminium(III) and gallium(III) triflates, M(OTf) 3 , and triglyme (G3). Liquid-phase speciation of these new SILs was studied by multinuclear NMR spectroscopy. Across the compositional range of G3 : M(OTf) 3 mixtures, both metals were found to be in a hexacoordinate environment, with both G3 and [OTf] - ligands present in the first coordination sphere, and apparently exchanging through a dynamic equilibrium. The Lewis acidity was quantified by the Gutmann acceptor number (AN) and compared to the performance of SILs as Lewis acidic catalysts in model [3 + 3] cycloadditions. Despite saturated coordination, AN values were relatively high, reaching AN = ca . 71-83 for Al-SILs and ca . 80-93 for Ga-SILs, corroborating the labile nature of the metal-ligand bonding. In a model catalytic reaction, SILs were fully soluble in the reaction mixtures, in contrast to the corresponding triflate salts. The catalytic performance of SILs exceeded that of the corresponding triflate salts, and Ga-SILs were more active than Al-SILs, in agreement with AN measurements. In conclusion, the new Group 13 SILs can be considered as soluble and catalytically active forms of their corresponding metal triflates, with potential uses in catalysis.

Tributyl citrate (TBC) plays a crucial role as a plasticizer, enhancing the flexibility of polymers such as polyvinyl chloride. Its biodegradability and non-toxic nature contribute to eco-friendly appeal, making it a preferred additive in diverse industries, including food packaging, medical devices, toys, and consumer goods. Herein, a method for the synthesis of TBC using inexpensive Brønsted acidic protic ionic liquids (ILs) in a two-phase reaction system is presented. The esterification process is carried out with high yield (>99 %), selectivity (up to 98 %) and short reaction time of 2 h. The catalyst in the form of IL shows excellent performance and stability, desirable for industrial applications., (© 2024 Wiley‐VCH GmbH.)

The chemical industry still requires development of environmentally friendly processes. Acid-catalysed chemical processes may cause environmental problems. Urgent need to replace conventional acids has forced the search for sustainable alternatives. Metal-containing ionic liquids have drawn considerable attention from scientists for many years. These compounds may exhibit very high Lewis acidity, which is usually dependent on the composition of the ionic liquid with the particular content of metal salt. Therefore, metal-containing ionic liquids have found a lot of applications and are successfully employed as catalysts, co-catalysts or reaction media in various fields of chemistry, especially in organic chemistry. Gallium(III)- and indium(III)-containing ionic liquids help to transfer the remarkable activity of metal salts into even more active and easier-to-handle forms of ionic liquids. This review highlights the wide range of possible applications and the high potential of metal-containing ionic liquids with special focus on Ga(III) and In(III), which may help to outline the framework for further development of the presented research topic and synthesis of new representatives of this group of compounds.

As a result of strict regulations of phthalate plasticizers, alternative non-phthalate forms are desired and increasingly used. This work presents a synthetic method for alternative plasticizers (dialkyl succinates and adipates) via esterification of succinic and adipic acid with alcohols: butan-1-ol and 2-ethylhexan-1-ol. Ionic liquids were synthesized by the reaction of triethylamine with over-equimolar (1:2.7) amounts of sulfuric(VI) acid, which were used as an acidic catalyst and solvent. The two-phase liquid-liquid system was formed during the reaction due to immiscibility of the esters with the ionic liquid. This phenomenon is a driving force of this process, shifting the equilibrium toward the product formation. As a result, dialkyl succinates and adipates were obtained in high yields (99%) and selectivities (>99%), under mild reaction conditions at 70-80 °C and using a 4:1 molar ratio of alcohol to acid and 15 mol% of catalyst. The catalyst was recycled 10 times without any loss of activity. This alternative method is highly competitive: it involves a simple procedure for product isolation as well as a high yield and purity of the resulting esters. These advantages make this method sustainable and promising for industrial applications.