Electrochemical Aminoxyl-Mediated Oxidation of Primary Alcohols in Lignin to Carboxylic Acids: Polymer Modification and Depolymerization.
Electrochemical Aminoxyl-Mediated Oxidation of Primary Alcohols in Lignin to Carboxylic Acids: Polymer Modification and Depolymerization.
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DOI：
10.1021/jacs.9b07243
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发表时间：
2019-09-25
影响因子：
15
通讯作者：
Stahl SS
中科院分区：
文献类型：
--
作者：
Rafiee M;Alherech M;Karlen SD;Stahl SS
发展了一种化学选择性氧化木质素中的伯醇生成相应的羧酸的电化学过程。电化学氧化反应在温和的碱性条件下进行，以2，2，6，6-四甲基-1-哌啶N-氧基(TEMPO)和4-乙酰氨基-TEMPO(ACT)为催化介质。木质素模型化合物和相关的醇被用来进行结构-反应性研究，以提供对反应选择性的来源的见解。将该方法应用于杨木木屑中提取的木质素的温和酸解氧化反应，得到了一种新型的聚电解质材料。对氧化木质素的凝胶渗透色谱数据表明，该材料的相对分子质量和分子量分布与提取木质素非常相似，但也有显著的差异。碱滴定结果表明，木质素中的酸含量显著增加，氧化木质素的水溶性比抽提木质素高得多。氧化木质素在酸性条件下的处理导致材料解聚为特征芳香单体，产率近30wt%。
An electrochemical process has been developed for chemoselective oxidation of primary alcohols in lignin to the corresponding carboxylic acids. The electrochemical oxidation reactions proceed under mildly basic conditions and employ 2,2,6,6-tetramethyl-1-piperidine N-oxyl (TEMPO) and 4-acetamido-TEMPO (ACT) as catalytic mediators. Lignin model compounds and related alcohols are used to conduct structure-reactivity studies that provide insights into the origin of the reaction selectivity. The method is applied to the oxidation of lignin extracted from poplar wood chips via a mild acidolysis method, and the reaction affords a novel polyelectrolyte material. Gel permeation chromatography data for the oxidized lignin shows that this material has a molecular weight and molecular weight distribution very similar to that of the extracted lignin, but notable differences are also evident. Base titration reveals a significant increase in the acid content, and the oxidized lignin has much higher water solubility relative to the extracted lignin. Treatment of the oxidized lignin under acidic conditions results in depolymerization of the material into characterized aromatic monomers in nearly 30 wt% yield.
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影响因子：
18.2
作者：
Bosque I;Magallanes G;Rigoulet M;Kärkäs MD;Stephenson CRJ
通讯作者：
Stephenson CRJ
影响因子：
5.2
作者：
Biannic, Berenger;Bozell, Joseph J.
通讯作者：
Bozell, Joseph J.
影响因子：
8.4
作者：
Garedew, Mahlet;Young-Farhat, Daniel;Saffron, Christopher M.
通讯作者：
Saffron, Christopher M.
DOI：
10.3390/molecules23040868
发表时间：
2018-04-10
期刊：
Molecules (Basel, Switzerland)
影响因子：
--
作者：
Chen J;Eraghi Kazzaz A;AlipoorMazandarani N;Hosseinpour Feizi Z;Fatehi P
通讯作者：
Fatehi P
影响因子：
8.4
作者：
Cardiel, Allison C.;Taitt, Brandon J.;Choi, Kyoung-Shin
通讯作者：
Choi, Kyoung-Shin