バイオマスの有効利用を指向した光と金属触媒を用いる炭素－炭素結合切断反応の開発

利用光和金属催化剂开发碳-碳键断裂反应以有效利用生物质

• 批准号: 16F16340
• 负责人: 村上 正浩
• 金额: $ 1.41万
• 依托单位: Kyoto University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for JSPS Fellows
• 财政年份: 2016
• 资助国家: 日本
• 起止时间: 2016-10-07 至 2019-03-31
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-16F16340/
• 关键词: alkene; C-C bond cleavage; photocatalysis; pyridine N-oxide; ortho-alkylation; photo redox; copper catalyst; リグニンモデルの分解

A new light/copper relayed system is developed for aerobic oxidative fragmentation of lignin model compounds having beta-O-4 and beta-1 linkage. Lignin model compounds are successfully broken down with an enhanced reaction efficiency and different product distribution in comparison to thermal copper-catalyzed aerobic degradation.In this study, we used the simple compound having a beta-O-4 linage as the model substrate because it represents the most abundant repeating unit existing in lignin and the investigation on its behavior toward light and a copper catalyst would provide us with an insight into a depolymerization process of native lignin under similar conditions. When the model substrate in 1,2-dichloroethane was irradiated with a blue LEDs lamp under air in the presence of Mes-Acr+ BF4-(2.0 mol %),copper(II) acetate (20 mol %), and sodium acetate (2.0 equiv), the substrate was consumed after 12 h. 3,4-Dimethoxybenzaldehyde and 2-methoxyphenyl formate were obtained in 66% isolated yield and 56% GC yield, respectively. Thus, carbon-carbon bonds contained in the beta-O-4 linage is cleaved. Next, the conditions for aerobic fragmentation were applied to another family of lignin model compound having a beta-1 linkage, which is the second most abundant repeating unit found in lignin. It was proved to be also viable substrate. Thus, our photo-catalyzed system could also be applied for lignin model compounds having a beta-1 linkage.

开发了一种新的光/铜接力体系，用于具有β-O-4和β-1键的木质素模型化合物的好氧氧化裂解。与热铜催化好氧降解相比，木质素模型化合物被成功地降解，反应效率提高，产物分布不同。我们使用了一种简单的化合物，由于木质素是木质素中存在的最丰富的重复单元，因此将木质素4作为模型底物，研究其对光和铜催化剂的反应行为将为我们提供一种新的思路在类似条件下进行天然木质素的解聚过程。当在Mes-Acr+ BF 4-（2.0摩尔%）、乙酸铜（II）（20摩尔%）和乙酸钠（2.0当量）存在下，在空气下用蓝色LED灯照射1，2-二氯乙烷中的模型基底时，基底在12小时后被消耗。分别以66%的分离产率和56%的GC产率获得3，4-二甲氧基苯甲醛和甲酸2-甲氧基苯酯。因此，β-O-4链中所含的碳-碳键被切断。接下来，将需氧片段化的条件应用于具有β-1键的另一个家族的木质素模型化合物，所述β-1键是木质素中发现的第二丰富的重复单元。它也被证明是可行的底物。因此，我们的光催化系统也可以应用于具有β-1键的木质素模型化合物。

项目成果

Light/Copper Relay for Aerobic Fragmentation of Lignin Model Compounds

• DOI: 10.1002/ajoc.201800520
• 发表时间: 2018-10
• 期刊: Asian Journal of Organic Chemistry
• 影响因子: 2.7
• 作者: Wang Zhou;Junki Nakahashi;T. Miura;M. Murakami

Ortho-Alkylation of Pyridine N-Oxide by Photo-Catalyzed Alkene

光催化烯烃对吡啶 N-氧化物的邻位烷基化

• 发表时间: 2018
• 作者: Wang Zhou