Selectively Upgrading Lignin Derivatives to Carboxylates through Electrochemical Oxidative C(OH)−C Bond Cleavage by a Mn‐Doped Cobalt Oxyhydroxide Catalyst. Issue 16 (10th March 2021)

• Record Type: Journal Article
• Authors: Zhou, Hua; Li, Zhenhua; Xu, Si‐Min; Lu, Lilin; Xu, Ming; Ji, Kaiyue; Ge, Ruixiang; Yan, Yifan; Ma, Lina; Kong, Xianggui; Zheng, Lirong; Duan, Haohong
• Is Part Of: Angewandte Chemie international edition. Volume 60:Issue 16(2021)
• Page Start: 8976
• Page End: 8982
• Publication Date: 2021-03-10
• Subjects: carboxylic acids -- C−C bond cleavage -- electrochemical oxidation -- hydrogen evolution -- lignin upgrading; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.202015431
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: Oxidative cleavage of C(OH)−C bonds to afford carboxylates is of significant importance for the petrochemical industry and biomass valorization. Here we report an efficient electrochemical strategy for the selective upgrading of lignin derivatives to carboxylates by a manganese‐doped cobalt oxyhydroxide (MnCoOOH) catalyst. A wide range of lignin‐derived substrates with C(OH)‐C or C(O)‐C units undergo efficient cleavage to corresponding carboxylates in excellent yields (80–99 %) and operational stability (200 h). Detailed investigations reveal a tandem oxidation mechanism that base from the electrolyte converts secondary alcohols and their derived ketones to reactive nucleophiles, which are oxidized by electrophilic oxygen species on MnCoOOH from water. As proof of concept, this approach was applied to upgrade lignin derivatives with C(OH)‐C or C(O)‐C motifs, achieving convergent transformation of lignin‐derived mixtures to benzoate and KA oil to adipate with 91.5 % and 64.2 % yields, respectively. Abstract : An electrochemical strategy has been developed for the oxidative cleavage of C(OH)−C bonds using a manganese‐doped cobalt oxyhydroxide catalyst under mild conditions. Preliminary studies demonstrate its application in upgrading lignin‐derived products with C(OH)‐C or C(O)‐C motifs, electrorefining them into valuable oxygenates, such as benzoate and adipate.