Recent advances in sustainable bio-based furanic materials are highlighted with a focus on structural and functional diversity, connected to practical applications of both linear and branched polymer types.

This work reveals ambident nucleophilic reactivity of imidazolium cations towards carbonyl compounds at the C2 or C4 carbene centers depending on the steric properties of the substrates and reaction conditions. Such an adaptive

2-Azidomethyl-5-ethynylfuran, a new ambivalent compound with both azide and alkyne moieties that can be used as a self-clickable monomer, is synthesized starting directly from renewable biomass. The reactivity of the azide group linked to furfural is tested via the efficient preparation of a broad range of furfural-containing triazoles in good to excellent yields using a 'green' copper(I)-catalyzed azide-alkyne cycloaddition procedure. Access to new bio-based chemicals and oligomeric materials via a click-chemistry approach is also demonstrated using this bio-derived building block.

C−H functionalization is one of the most convenient and powerful tools in the arsenal of modern chemistry, deservedly nominated as the “Holy Grail” of organic synthesis. A frequent disadvantage of this method is the need for harsh reaction conditions to carry out transformations of inert C−H bonds, which limits the possibility of its use for modifying less stable substrates. Biomass‐derived furan platform chemicals, which have a relatively unstable aromatic furan core and highly reactive side chain substituents, are extremely promising and valuable organic molecules that are currently widely used in a variety of research and industrial fields. The high sensitivity of furan derivatives to acids, strong oxidants, and high temperatures significantly limits the use of classical methods of C−H functionalization for their modification. New methods of catalytic functionalization of non‐reactive furan cores are urgently required to obtain a new generation of materials with controlled properties and potentially bioactive substances.