Protic, Aprotic, and Choline-Derived Ionic Liquids: Toward Enhancing the Accessibility of Hardwood and Softwood was written by Rigual, Victoria;Ovejero-Perez, Antonio;Rivas, Sandra;Dominguez, Juan C.;Alonso, M. Virginia;Oliet, Mercedes;Rodriguez, Francisco. And the article was included in ACS Sustainable Chemistry & Engineering in 2020.Reference of 35487-17-3 This article mentions the following:
A side-by-side comparison of softwood (pine) vs. hardwood (eucalyptus) pretreatment using 3 protic, 3 aprotic, and 3 choline-derived ionic liquids (ILs) is proposed. While the protic ionic liquid 2-hydroxyethylammonium formate leads to alkali lignin dissolution at 30°C after 1 h, the lack of interactions with the whole-cell wall limits the biomass disruption. On the contrary, the protic ionic liquid 1-methylimidazolium chloride produces a catalytic effect that extracts almost all of the hemicelluloses, and partially the lignin. Remarkable digestibilities are obtained with choline acetate ([Ch][OAc]) in eucalyptus (69%), while in pine, protic, and choline-derived ILs tested do not appear to be real “greener” alternatives to conventional ILs such as 1-ethyl-3-methylimidazolium acetate (the highest digestibility, 84%). Solid morphol. revealed a smoother surface in pine pretreated with [Mim][Cl], and confocal fluorescence microscopy was used to distinguish surface holocellulose and lignin, highlighting differences in the accessibility of hardwood vs. softwood due to the presence of surface lignin. Two-dimensional NMR spectroscopy of saccharified samples pretreated with [Ch][OAc] showed the presence of groups derived from acetate. Finally, thermogravimetric anal. and spectroscopy techniques reveal the difficulties in recovering the ionic liquid and conclude a work that describes the strengths and weaknesses of the ILs and biomasses studied. In the experiment, the researchers used many compounds, for example, 1-Methyl-1H-imidazol-3-ium chloride (cas: 35487-17-3Reference of 35487-17-3).
1-Methyl-1H-imidazol-3-ium chloride (cas: 35487-17-3) belongs to imidazole derivatives. Many natural products, especially alkaloids, contain the imidazole ring. These imidazoles share the 1,3-C3N2 ring but feature varied substituents. The pharmacophore of imidazole exists in bioactive compounds including amino acids, plant growth regulators and therapeutic agents.n increase of the alkyl chain length of the alcohols. Reference of 35487-17-3
Referemce:
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem