On the Valorisation of Chitin‐Derived Furans by Milling

Chitin‐derived furans offer a sustainable alternative feedstock for nitrogen appended aromatic compounds. Herein, we address the challenge of using chitin‐derived furans, 3‐acetamido‐5‐acetylfuran (3A5AF) and 3‐acetamido‐5‐furfural aldehyde (3A5F), to favour the formation of exo Diels–Alder adducts and 4‑acetylaminophthalimides respectively, using a mechanochemical ball‐milling technique. Mechanochemical activation is explored through the synthesis of 7‐oxa‐norbornene backbones with novel substitution pattern from 3A5AF in yields up to 77% and improved exo:endo selectivity compared to solution‐phase reactions. The synthesis of 4‑acetylaminophthalimides from 3A5F in yields up to 79% is also showcased from hydrazone derivatives.