Protection Strategies for the Conversion of Biobased Furanics to Chemical Building Blocks

Abstract

In recent years, the urgency to replace fossil-based resources by renewable biomass for obtaining chemical building blocks has only increased. Carbohydrate-derived furanic compounds are regarded as promising platforms for a renewable value chain. The high reactivity of such biobased intermediates requires the development of novel catalytic chemistry to enhance product yield. The protection of reactive functional groups provides a way to improve the product selectivity. Such protection strategies are common practice in the synthesis of fine chemicals and pharmaceuticals but are not fully explored for the conversion of furanic compounds. In this perspective, several examples of protection strategies focusing on the selective passivation of 5-HMF are discussed. Formation and removal of these protection groups are highlighted as well as the application of the neutralized 5-HMF in further processing. A guide for selecting the appropriate protection strategy depending on the targeted chemistry and operating conditions is provided.

Hydrodeoxygenation of potential platform chemicals derived from biomass to fuels and chemicals

“…More detailed protection strategies were summarized in a very recent review. 27 Another issue for handling HMF arises from the negative effect of trace impurities on the catalytic conversions of HMF. 28 HMF synthesis typically uses unconventional solvents such as dimethyl sulfoxide (DMSO), and the presence of trace DMSO greatly affects the hydrogenation of HMF.…”

Computational survey of humin formation from 5-(hydroxymethyl)furfural under basic conditions

“…Although we did not consider the catalyst or molecular oxygen on the metal support in this study, the results shown in this paper suggest a deeper understanding of humin formation in various basic solutions and the effect of acetal protection on HMF. [36][37][38]…”

A Protection Strategy for High‐yield Synthesis of Dimethyl Furan‐2,5‐dicarboxylate from 5‐Hydroxymethylfurfural Using Methanol as an Acetalizing Agent

“…Protection of the highly reactive formyl group as its acetal with 1,3-propanediol (PD) suppresses such undesirable side reactions and allows the use of concentrated HMF solutions (10-20 wt %) for various hydrogenation and oxidation reactions. [28][29][30][31][32][33] We earlier established the potential of acetalized HMF with PD (PD-HMF) as a reactant in the one-pot oxidation and oxidative esterification with Au/CeO 2 and two equivalents of Na 2 CO 3 to synthesize FDCA (> 90 %) and MFDC (> 90 %), respectively, using concentrated PD-HMF solutions (> 10 wt %) (Schemes 1A and 1B). [30,31] The six-membered cyclic acetal ring in PD-HMF suppresses byproduct formation in concentrated solutions.…”