Mn(I)‐Complex Catalyzed Upcycling of Polyethylene Terephthalate to α‐Hydroxy Carboxylic Acids

Abstract

Abstract The chemical upcycling of poly(ethylene terephthalate) (PET) waste into value‐added products presents a promising strategy to address global plastic pollution. Here, we report a manganese‐catalyzed, one‐pot approach for tandem PET depolymerization and acceptorless dehydrogenative coupling (ADC) to selectively produce α‐hydroxycarboxylic acids (α‐HCAs), including glycolic, lactic, and higher‐value derivatives, along with terephthalic acid (TPA) and H 2 gas. Employing bench‐stable (PNP)Mn(I)‐pincer complexes, this cascade process operates under mild conditions (120–140 °C) and accommodates a broad range of primary alcohol coupling partners, enabling the synthesis of valuable biodegradable polymer precursors (glycolic and lactic acid) and higher α‐HCAs. Notably, the system exhibits exceptional tolerance to common plastic additives and requires no energy‐intensive pretreatment, achieving near‐quantitative TPA recovery and significant H 2 evolution. This work demonstrates how base‐metal catalysis can bridge plastic waste remediation and sustainable chemical synthesis, offering a practical pathway toward circular polymer economies.