Aromatics play essential and unique roles in the areas ranging from synthetic chemistry to the manufacturing industry. Production of aromatics from biomass is of great fundamental interest and practical importance to ease the burden of fossil resources. This work delineates a one-step route for the synthesis of renewable aromatics from various biobased furanics and dienophiles by acidic ionic liquids at mild conditions. [Bmim]­HSO4 was used as a catalyst and solvent for the direct conversion of 2,5-dimethylfuran and acrylic acid into p-xylene and 2,5-dimethylbenzoic acid; up to 89% aromatic selectivity was achieved at 87% conversion of 2,5-dimethylfuran at room temperature and atmospheric pressure, and totally 84% selectivity of p-xylene can be obtained with a subsequent decarboxylation reaction. The reaction mechanism study supplemented with isotopic tracing and DFT calculations revealed the lowest-energy pathway for the two main products. Various starting materials were studied for further extensions of the method, and it turned out that electron-donating methyl groups on the furan ring played crucial roles on the activation of dehydration and decarboxylation processes. This work provided convenient access to industrial commodity aromatics from fully biomass-derived feedstocks and thus can be regarded more economically and environmentally feasible.

The production of aromatic platform chemicals from biomass-derived feedstocks is of considerable importance in biomass conversion. However, the development of effective routes with simple steps and under mild conditions is still challenging. In this work, we report an original route for the direct synthesis of p-xylene from 2,5-dimethylfuran and acrylic acid catalyzed by scandium(III) triflate (Sc(OTf) ) in 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([Emim]NTf ) under mild conditions. An overall 63 % selectivity towards p-xylene and 78 % selectivity towards aromatics were obtained at 90 % conversion of 2,5-dimethylfuran by enhancing the dehydration and introducing an extra one-pot decarboxylation step. Furthermore, various dienes and dienophiles were employed as reactants to extend the substrate scope. The aromatic compounds were obtained in moderate yields, which proved the potential of the method to be a generic approach for the conversion of bio-based furanics into renewable aromatics.

A novel pseudo-homogeneous catalyst system consisting of noble metal nanoparticles and ionic liquids is developed for the selective reductive cleavage of C–O and hydrodeoxygenation under mild conditions.