One‐Pot Deoxygenation of Fructose to Furfuryl Alcohol by Sequential Dehydration and Decarbonylation

Abstract

Fructose was deoxygenated to furfuryl alcohol (FFA) by tandem dehydration and decarbonylation in one pot over the AlCl3⋅6 H2O/Pd(OAc)2 catalyst combination to give a high FFA yield of 40.6 %. AlCl3⋅6 H2O behaves as an effective Lewis acid to catalyze the dehydration of fructose to 5‐hydroxymethylfurfural (HMF), and subsequently, Pd(OAc)2 catalyzes the removal of a CO moiety from HMF to produce FFA selectively. The hydroxyl group on the HMF intermediate was stabilized by poly(1‐vinyl‐2‐pyrrolidinone) through an intermolecular hydrogen bond, which accelerated the dehydration of fructose and inhibited the hydrogenation of HMF by formic acid. The decarbonylation of HMF was promoted and the unwanted decomposition of fructose was inhibited through the use of 4 Å molecular sieves. This research highlights a “one‐pot” catalytic system to transform renewable carbohydrates into fine chemicals by tandem dehydration and decarbonylation reactions without the separation or purification of HMF.

Microwave‐Assisted Decarbonylation of Biomass‐Derived Aldehydes using Pd‐Doped Hydrotalcites

“…Furfural and HMF decarbonylation is primarily performed in 1,4‐dioxane (Scheme ), a polar aprotic solvent often used for lignocellulose pretreatment. However, the short‐term acute toxicity of 1,4‐dioxane (symptoms include vertigo, drowsiness, anorexia, and ear/nose/lung irritation), and long‐term effects resulting from chronic exposure (such as hepatotoxicity, neurotoxicity, and carcinogenicity in animal models) suggest dioxane is not suitable for the sustainable, large‐scale processing of biomass.…”

“…Although some operate under relatively mild conditions, most require high catalyst loading (from 0.5 mol % for Ir to 16 mol % for heptanal decarbonylation over Pd) . In a recent example, Hu and co‐workers reported the tandem dehydration–decarbonylation of fructose using a Lewis acid for dehydration (aluminum chloride) and palladium acetate for decarbonylation, but required 11 mol % Pd to achieve full conversion with a turnover frequency (TOF) of only approximately 3 h −1 . Heterogeneous catalysts reported for HMF and furfural decarbonylation are all Pd‐derived (Scheme ), but a significant improvement in efficiency (TOF range from 1–26 h −1 ) and robustness is needed.…”

One‐step Conversion of Fructose to Furfuryl Alcohol in a Continuous Fixed‐bed Reactor: The Important Role of Supports

“…With increasing of concern about environmental problems and cost‐efficiency, the concept of “one‐pot” reaction, using multifunctional catalyst or catalyst combination, have been developed to directly convert monosaccharide (fructose, glucose and xylose) to furan derivatives in batch or fixed‐bed reactor . In particular, J. H. Dai and co‐worker developed a batch process combined dehydration and decarbonylation, in which the fructose could be directly converted to FOL (yield 40.6 %). Additionally, it was shown by Cui .…”

“…Combined with the zeolites and Pd‐based catalysts, conversion of fructose into FOL is achieved in continuously fixed‐bed reactor, eliminating the need for separation step (see Scheme and Supporting Information S1). Unsatisfactorily, in most reported examples dealing with the production of FOL from HMF or carbohydrates, the toxic dioxane, which is hazardous to environment and operators, was used as solvent ,,,…”

Pd‐Catalysed Decarbonylation Free Approach to Carbonylative Esterification of 5‐HMF to Its Aryl Esters Synthesis Using Aryl Halides and Oxalic Acid as C1 Source

“…In most of the reported protocols, 5-HMF has been majorly highlighted for the decarbonylation of À CHO functional group under the influence of various metals such as Pd, Rh, Ru and Ir-catalysed conditions. [5][6][7][8][9][10][11][12][13] In 2015, Rauchfuss and co-workers reported the Pd/C-catalysed decarbonylation of 5-HMF to corresponding furfuryl alcohol synthesis in good yield at 120°C in 1,4-dioxane solvent conditions (Scheme 1a). [14] Furthermore, Kawanami et al also observed the labile nature of the aldehyde (À CHO) group of 5-HMF under Pd/Al 2 O 3 catalyst conditions under compressed CO 2 and got furfuryl alcohol as major product at 145°C (Scheme 1b).…”