Aluminum (III) chloride-catalyzed transformation of biomass derived furans to Benzo[b]furans

In the present study, biomass-derived furans were identified as desirable feedstock for synthesizing benzo [b]furans via a simple one-pot reaction under mild conditions. Under a typical reaction condition, i.e. 75 vol% acetic acid solution and 5 wt% AlCl3 catalyst at 140 °C for 2 h, benzo [b]furan can be synthesized from furan with a yield of 31 wt% and a selectivity of 90%. Furthermore, a general reaction pathway was identified, i.e. various benzo [b]furans can be directly produced from two furans, except for when 2,5-dimethyfuran is the only reactant. This work opens a novel sustainable avenue to synthesize benzo [b]furan derivatives from furans with targeted substitutes.