Biomass to drugs: Green production of salicylic acid from 2-furoic acid in two steps

Salicylic acid, generally produced by chemical synthesis based on petrochemical products, is a vital organic acid and widely used in the pharmaceutical synthesis. This work developed a new and green route for the production of salicylic acid from biomass-derived 2-furoic acid in two steps. Firstly, 2 mmol 2-furoic acid was creatively converted to 2,3-benzofuran using HZSM-5 (Si/Al=130) at 280 °C for 1.5 h under 100 psi N2; and then the oxidation of 2,3-benzofuran to salicylate was conducted with tert‑butyl hydroperoxide under basic condition without metal catalyst at 120 °C for 1 h. The stability of the catalyst for the first step and the possible reaction pathway for the second step based on the control experiments was properly envisioned. Regardless of limited salicylic acid yield (16%) from 2-furoic acid, this work paves a potentially feasible pathway for the preparation of drugs from biomass.