The synthesis of ideal, well-defined, functionalized lignins is of great significance for realizing the full valorization potential of lignocellulosic biomass. Here, the application of acidified triethylammonium triflate is reported, allowing for the selective benzylic alkoxylation of different lignins at room temperature. Full benzylic alkoxylation of typically hard-to-process, high-molecular-weight lignin was achieved in this medium by simple mixing with different alcohols. Limited lignin degradation was observed, and lignin modification was also achieved within the lignocellulosic matrix. This allows the method to be used as a biomass pretreatment, which was shown to also enhance enzymatic saccharification. The reactivity, stability, and hydrophobicity of the lignin can be tuned based on the alcohol used. Effective recovery of the ionic liquid and recycling of the ionic liquid was achieved. Thus, a straightforward mild method is demonstrated to introduce new functionality in lignin, allowing it to be tuned towards novel applications.

理想、定义明确、功能化的木质素的合成对于实现木质纤维素生物质的全部增值潜力具有重要意义。在这里，报告了酸化三乙基三氟甲磺酸铵的应用，允许在室温下对不同的木质素进行选择性苄基烷氧基化。通过与不同醇的简单混合，在这种介质中实现了通常难以加工的高分子量木质素的完全苄基烷氧基化。观察到有限的木质素降解，并且在木质纤维素基质内也实现了木质素改性。这使得该方法可以用作生物质预处理，这也被证明可以增强酶促糖化。木质素的反应性、稳定性和疏水性可以根据所使用的醇进行调整。实现了离子液体的有效回收和离子液体的循环利用。因此，一种简单的温和方法被证明可以在木质素中引入新功能，使其能够适应新的应用。