Modification of poly(ethylene- <i>alt</i> -maleic anhydride) via one-pot cascade esterification and Passerini three-component reaction

The Passerini three-component reaction (P-3CR) has always been a versatile strategy in polymer science, enabling the formation of complex architectures with high atom and step economy. In this study, we demonstrate the in-situ modification of poly(ethylene-&lt;i&gt;alt&lt;/i&gt;-maleic anhydride) (PEMA) &lt;i&gt;via&lt;/i&gt; one-pot cascade esterification and P-3CR using a wide range of aldehydes, isocyanides, and alcohols. The optimization study revealed that the most efficient temperature for the Passerini reaction was 60 °C with a substrate ratio of 2:2:2 for alcohol:aldehyde:isocyanide per repeating unit of the polymer. Polymer diversification was also studied to demonstrate the high functional group tolerance of this reaction. The obtained polymers were characterized in detail using spectroscopic methods, such as NMR, GPC, and FTIR. It was observed that the Passerini reaction proceeded with high efficiency, accompanied by the formation of functional ester derivatives. Being additive-free, energy-saving, and operationally simple methods, it is demonstrated that the combination of anhydride structures with P-3CR has been a remarkable alternative in synthetic polymer chemistry for developing complex architectures.