Więcławik Justyna, Brzęczek-Szafran Alina, Jurczyk Sebastian, Matuszek Karolina, Swadźba-Kwaśny Małgorzata, Chrobok Anna
Department of Organic Chemical Technology and Petrochemistry, Faculty of Chemistry, Silesian University of Technology, Bolesława Krzywoustego 4, 44-100 Gliwice, Poland.
Institute for Engineering of Polymer Materials and Dyes, Lukasiewicz Research Network, Sklodowskiej-Curie 55, PL-87100 Torun, Poland.
Dalton Trans. 2024 Dec 10;53(48):19143-19152. doi: 10.1039/d4dt02314e.
This work reports on the first solvate ionic liquids (SILs) based on aluminium(III) and gallium(III) triflates, M(OTf), and triglyme (G3). Liquid-phase speciation of these new SILs was studied by multinuclear NMR spectroscopy. Across the compositional range of G3 : M(OTf) 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 = . 71-83 for Al-SILs and . 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.
这项工作报道了基于三氟甲磺酸铝（III）和三氟甲磺酸镓（III）（M(OTf)）以及三甘醇二甲醚（G3）的首批溶剂化物离子液体（SILs）。通过多核核磁共振光谱研究了这些新型SILs的液相形态。在G3∶M(OTf)混合物的组成范围内，发现两种金属均处于六配位环境，第一配位层中同时存在G3和[OTf]配体，且显然通过动态平衡进行交换。通过古特曼受体数（AN）对路易斯酸度进行了量化，并与SILs作为路易斯酸催化剂在模型[3 + 3]环加成反应中的性能进行了比较。尽管配位饱和，但AN值相对较高，铝基SILs的AN值达到71 - 83，镓基SILs的AN值达到80 - 93，这证实了金属 - 配体键的不稳定性质。在模型催化反应中，与相应的三氟甲磺酸盐相比，SILs完全可溶于反应混合物中。SILs的催化性能超过了相应的三氟甲磺酸盐，并且镓基SILs比铝基SILs更具活性，这与AN测量结果一致。总之，新型13族SILs可被视为其相应金属三氟甲磺酸盐的可溶且具有催化活性的形式，在催化领域具有潜在应用。
