Department of Chemistry, Michigan State University, East Lansing, MI, 48824, USA.
Department of Biochemistry & Molecular Biology, Michigan State University, East Lansing, MI, 48824, USA.
ChemSusChem. 2020 Sep 7;13(17):4394-4399. doi: 10.1002/cssc.202001238. Epub 2020 Aug 7.
Lignin may serve as a renewable feedstock for the production of chemicals and fuels if mild, scalable processes for its depolymerization can be devised. The use of small organic thiols represents a bioinspired strategy to cleave the β-O-4 bond, the most common linkage in lignin. In the present study, synthetic β-O-4 linked polymers were treated with organic thiols, yielding up to 90 % cleaved monomer products. Lignin extracted from poplar was also treated with organic thiols resulting in molecular weight reductions as high as 65 % (M ) in oxidized lignin. Thiol-based cleavage of other lignin linkages was also explored in small-molecule model systems to uncover additional potential pathways by which thiols might depolymerize lignin. The success of thiol-mediated cleavage on model dimers, polymers, and biomass-derived lignin illustrates the potential utility of small redox-active molecules to penetrate complex polymer matrices for depolymerization and subsequent valorization of lignin into fuels and chemicals.
如果能够设计出温和、可扩展的木质素解聚工艺，木质素可能成为生产化学品和燃料的可再生原料。使用小分子有机硫醇代表了一种生物启发策略，可以切割β-O-4 键，这是木质素中最常见的键。在本研究中，用有机硫醇处理合成的β-O-4 键连接的聚合物，得到高达 90%的断裂单体产物。用有机硫醇处理从杨木中提取的木质素，导致氧化木质素的分子量降低高达 65%（M）。还在小分子模型体系中探索了基于硫醇的其他木质素键的断裂，以揭示硫醇可能解聚木质素的其他潜在途径。在模型二聚体、聚合物和生物质衍生木质素上，硫醇介导的断裂的成功表明，小分子氧化还原活性分子具有潜在的用途，可以穿透复杂的聚合物基质，将木质素解聚为燃料和化学品。
