A New Strategy for the Synthesis of Valuable Benzenoid Aromatics from Bioderived 5-Hydroxymethylfurfural (HMF) under Mild Conditions

Abstract

Abstract To mitigate the effects of global warming, synthesis of aromatic chemicals that play indispensable roles in our daily lives from renewable resources is of great importance. Herein, we present a new strategy to synthesize bio-based C6-aromatics from 5-hydroxymethylfurfural (HMF) under very mild conditions. The versatile bio-based intermediate 2,5-dioxohexanal (DOH) containing three carbonyl groups was successfully synthesized from HMF in high yield. Simple intramolecular aldol condensation of DOH and secondary amines, depending on the acid, selectively produced a range of bio-based 4-substituted phenols and 1,4-di-(dialkylamino)benzenes (Wurster’s blue analogues) in satisfactory yields. In the absence of amines, the industrially important hydroquinone was also synthesized from DOH under acidic condition. Using a similar approach, catechol was prepared from HMF via 4,5-dioxohexanal (DOA) as intermediate.