Synthesis of bio-aryl esters and ethers through arylation of lignin and lignocellulose

The complete functionalization of lignin depolymerization fragments into value-added chemicals is essential for enhancing atom economy in biorefineries, yet it remains a significant challenge due to the structural complexity and low reactivity of cleavage products. To address this, we developed a one-pot protocol utilizing diaryliodonium salts as arylating agents to achieve the simultaneous depolymerization and full functionalization of lignin and lignocellulose. Mechanistic investigations revealed a reaction pathway involving the sequential cleavage of lignin C–O/C–C bonds followed by comprehensive arylation of the resulting fragments. This method delivers bio-based aryl ethers and esters in high yields (up to 85%) for the transformation of lignin model compounds. Moreover, this strategy is particularly notable for its capacity to directly transform raw lignocellulosic wood into valuable short-chain carboxylates and desired aryl derivatives. By offering a sustainable and widely applicable approach, this protocol maximizes atom utilization in the production of diverse bio-based chemicals, thereby offering a robust framework for integrated lignin valorization in biorefineries.