Electrochemical Coupling of Biomass‐Derived Acids: New C₈ Platforms for Renewable Polymers and Fuels

Abstract

Electrolysis of biomass‐derived carbonyl compounds is an alternative to condensation chemistry for supplying products with chain length >C6 for biofuels and renewable materials production. Kolbe coupling of biomass‐derived levulinic acid is used to obtain 2,7‐octanedione, a new platform molecule only two low process‐intensity steps removed from raw biomass. Hydrogenation to 2,7‐octanediol provides a chiral secondary diol largely unknown to polymer chemistry, whereas intramolecular aldol condensation followed by hydrogenation yields branched cycloalkanes suitable for use as high‐octane, cellulosic gasoline. Analogous electrolysis of an itaconic acid‐derived methylsuccinic monoester yields a chiral 2,5‐dimethyladipic acid diester, another underutilized monomer owing to lack of availability.

New bio-based monomers: tuneable polyester properties using branched diols from biomass

“…2,5-Furandicarbonyl chloride 3 and 2,7-octanediol 7 were prepared using previously reported methods. 7,11 Diols were dried over molecular sieves prior to use in the polymerisations. Angelica lactone dimer 19 was prepared based on a literature procedure.…”

(Non-)Kolbe electrolysis in biomass valorization – a discussion of potential applications

“…103 According to a recent study, the coupling product of levulinic acid 2,7-octanedione (65% yield) can be hydrogenated into 2,7-octanediol (94% yield)a potential monomer for the synthesis of polyesters. 104 The copolyesters poly(2,7-octanediol) terephthalate and poly(2,7-octanediol)-2,5-furanoate were obtained in fair yields (54-63%) with a medium chain length (3978-8531 Da), showing sufficient stability and a low polydispersity index (M w /M N ). The synthesised 2,7-octanedione can also be further reacted in an aldol condensation to form 1-methylcyclopentyl ketone or 3-methylcycloheptanone.…”

Electrocatalytic upgrading of itaconic acid to methylsuccinic acid using fermentation broth as a substrate solution

“…The obtained product 2,5-dimethyladipic acid after release of the ester groups might possess very promising characteristics in the polymer industry. 18 One of the key steps in the production of biofuels or valueadded chemicals from biomass presents a suitable connection between the highly selective biotechnological transformation of biomass, e.g. cellulose, into platform chemicals such as ethanol and lactic acid or IA with subsequent processing.…”