Premium
Solvent Effects on Degradative Condensation Side Reactions of Fructose in Its Initial Conversion to 5‐Hydroxymethylfurfural
Author(s) -
Fu Xing,
Hu Yexin,
Zhang Yanru,
Zhang Yucheng,
Tang Dianyong,
Zhu Liangfang,
Hu Changwei
Publication year - 2020
Publication title -
chemsuschem
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.412
H-Index - 157
eISSN - 1864-564X
pISSN - 1864-5631
DOI - 10.1002/cssc.201902309
Subject(s) - chemistry , levulinic acid , hexose , fructose , organic chemistry , solvent , hydroxymethylfurfural , acetic acid , dimethoxymethane , formic acid , condensation reaction , tautomer , solvent effects , condensation , catalysis , furfural , enzyme , physics , thermodynamics
The degradative condensation of hexose, which originates from the C−C cleavage of hexose and condensation of degraded hexose fragment, is one of the possible reaction pathways for the formation of humins in hexose dehydration to 5‐hydroxymethylfurfural (HMF). Herein, the impacts of several polar aprotic solvents on the degradative condensation of fructose to small‐molecule carboxylic acids and oligomers (possible precursors of humins) are reported. In particular, a close relationship between the tautomeric distribution of fructose in solvents and the mechanism of degradative condensation is demonstrated. Typically, α‐fructofuranose in 1,4‐dioxane and acyclic open‐chain fructose in THF favor the conversion of fructose to formic acid and oligomers; α‐fructopyranose in γ‐valerolactone or N ‐methylpyrrolidone favors levulinic acid and oligomers, whereas β‐fructopyranose in 4‐methyl‐2‐pentanone favors acetic acid and corresponding oligomers. This close correlation highlights a general understanding of the solvent‐controlled formation of oligomers, which represents an important step toward the rational design of effective solvent systems for HMF production.