Biomass to Aromatic Amine Module: Alkali Catalytic Conversion of N‐Acetylglucosamine into Unsubstituted 3‐Acetamidofuran by Retro‐Aldol Condensation

Abstract

Aminofurans are widely used in drug synthesis as aromatic modules analogous to aniline. However, unsubstituted aminofuran compounds are difficult to prepare. In this study, a process for the selective conversion of N‐acetyl‐d‐glucosamine (NAG) into unsubstituted 3‐acetamidofuran (3AF) is developed. The yield of 3AF from NAG catalyzed by a ternary Ba(OH)2−H3BO3−NaCl catalytic system in N‐methylpyrrolidone at 180 °C for 20 min can reach 73.9 %. Mechanistic studies reveal that the pathway to 3AF starts with a base‐promoted retro‐aldol condensation of the ring‐opened NAG, affording the key intermediate N‐acetylerythrosamine. Judicious selection of the catalyst system and conditions enables the selective conversion of biomass‐derived NAG into 3AF or 3‐acetamido‐5‐acetylfuran.

Catalytic conversion of chitin-based biomass to nitrogen-containing chemicals

“…discovered a ternary Ba(OH) 2 -H 3 BO 3 -NaCl catalytic system to convert NAG to 3AF. 102 According to the control experiments and the high performance liquid chromatography-mass spectrometry analyses, 3A5AF was not the intermediate for 3AF. On the contrary, it is deduced that the NAG first underwent retro-aldol condensation at the C4-C5 position to afford glycolaldehyde and NAE.…”

Valorization of the Exoskeletons of Crustaceans in Seafood Wastes to Chemicals in Renewable Solvents: A Catalytic and Mechanistic Study

“…An efficient protocol involving 3A5AF for the preparation of functionally rich 3-amidofurans, which are valuable functionalized N-containing substances from chitin, was developed by Sperry’s group . Gan et al recently reported the valorization of NAG to unsubstituted 3-acetamidofuran . Liu and co-workers developed ionic-liquid-based systems for LA production from chitin and even crab shells. , The dehydration of N -acetylglucosamine to enantiopure dihydroxyethyl acetamidofuran was recently reported by Minnaard and co-workers .…”

“…55 Gan et al recently reported the valorization of NAG to unsubstituted 3-acetamidofuran. 56 Liu and co-workers developed ionic-liquid-based systems for LA production from chitin and even crab shells. 57,58 The dehydration of N-acetylglucosamine to enantiopure dihydroxyethyl acetamidofuran was recently reported by Minnaard and co-workers.…”