wood flour for vanillin production. Further mechanical investigation with lignin model compounds suggested that the vanillin formation occurred mainly through following successive reactions: alkaline-catalyzed degradation of β-ether linkages in middle units of lignin polymer to form a glycerol end group, oxidation of the glycerol end group by O2 to a HCαO moiety, and release of vanillin from the HCαO
天然软木木质素在 Bu 4 NOH水溶液中的有氧氧化促进了香兰素(4-羟基-3-甲氧基苯甲醛)的有效生产,香兰素是工业中的平台化学品之一。在 Bu 4中的 O 2下 120 °C氧化日本柳杉木粉 4 h基于起始材料的 Klason 木质素含量,基于 NOH 的水溶液以 23.2 wt% 的产率生产香草醛。这一产率与相同材料的碱性硝基苯氧化(27.2%)相当,这表明我们的好氧氧化充分利用了木粉生产香草醛的潜力。对木质素模型化合物的进一步力学研究表明,香草醛的形成主要通过以下连续反应发生:碱性催化降解木质素聚合物中间单元中的 β-醚键以形成甘油端基,甘油端基被 O 2氧化到 HC α O 部分,并从 HC α O 端释放香草醛。BU高性能的原因之一4 NOH 用于香兰素生产的解释是有机化学中的一般理解,即 Bu 4 OH 是比简单碱(例如NaOH)更强的碱。另一个更基本的机械方面是 Bu 4 N
Gierer,J.; Pettersson,I., Canadian Journal of Chemistry, 1977, vol. 55, p. 593 - 599
作者:Gierer,J.、Pettersson,I.
DOI:——
日期:——
Selective Oxidation of Lignin Model Compounds
作者:Ruili Gao、Yanding Li、Hoon Kim、Justin K. Mobley、John Ralph
DOI:10.1002/cssc.201800598
日期:2018.7.11
planet's most abundant renewable source of aromatic compounds, is difficult to degrade efficiently to welldefined aromatics. We developed a microwave‐assisted catalytic Swern oxidation system using an easily prepared catalyst, MoO2Cl2(DMSO)2, and DMSO as the solvent and oxidant. It demonstrated high efficiency in transforming lignin model compounds containing the units and functional groups found in