Biomass-Modified Zirconium-Based Catalyst for One-Pot Reductive Etherification of Bioderived Aldehydes to Furanic Diether

The furanic diether of 2,5-bis(isopropoxymethyl)furan (BPMF) derived from 5-hydroxymethylfurfural (HMF) can be used as a biobased fuel or fuel additive. It is highly desirable but challenging to develop a one-pot process for the transformation of HMF into BPMF because it is a cascade sequence reaction involving reduction and etherification reactions over multifunctional acid catalysts. In this work, zirconium-based catalysts were facilely prepared from a zirconium salt, sulfosalicylic acid, and biomass by a simple hydrothermal method. The obtained catalyst with both Brønsted and Lewis acids (BA and LA, respectively) can transform HMF into BPMF with a yield of 92.4% in 2-propanol by Meerwein–Ponndorf–Verley reduction and etherification in a one-pot strategy. Additionally, the reaction pathway and mechanism of the reductive etherification reaction was investigated and is presented. This work proposes an approach for the preparation of a solid acid catalyst with multifunctional BA and LA for reductive etherification of aldehydes to ethers.