Synthesis and Performance of Biobased Surfactants Prepared by the One-Pot Reductive Amination of l-Arabinose and d-Galacturonic Acid

Abstract

Herein, we report a method for the synthesis of biobased surfactants derived from sugar beet pulp (SBP) monosaccharides, L-Ara and D-GalA. The surfactants were prepared via one-pot reductive amination, allowing the introduction of different alkyl chain lengths and methyl modifications. Optimal reaction conditions were established to achieve high yields and easy purification. The synthesized surfactants including the tertiary amines exhibited desirable properties, including solubility, foamability, and reduction of surface tension. Notably, the anionic surfactants derived from D-GalA demonstrated better solubility and foam performance compared to those derived from L-Ara. In addition, these surfactants exhibited surface tension and critical micelle concentration (CMC) comparable to those of the commercial surfactant sodium lauryl ether sulfate (SLES). Furthermore, the biodegradable surfactant GalA1.8 displayed excellent emulsifying properties and low skin irritation potential. On the L-Ara surfactant with a short chain, Ara1.6 has potential as a hydrotrope. These findings suggest that biobased surfactants derived from SBP monosaccharides have promising applications in various industries, including pharmaceuticals, cosmetics, detergents, and chemicals.

The synthesis of fructose-based surfactants

“…Finally, we determined the foaming and emulsification behaviour of our surfactants. Foaming experiments of C 8 -8 and C 10 -9 were carried out according to literature 16 and experimentally compared to the well-known surfactant SDS (see ESI † ). An initial experiment demonstrated that for all three surfactants, the foam was stable for at least 10 min.…”

“…Very recently, the reductive amination of arabinose and galacturonic acid with long chain aliphatic amines has been reported to yield versatile surfactants. 16 …”

Synthesis and Performance of Bio‐Based Amphoteric Surfactants

“…These sugars can be obtained from a non‐food biomass side stream, such as sugar beet pulp (SBP) [29] . We applied our recently reported two‐step one‐pot approach to reductively aminate monosaccharides to afford tertiary amine containing surfactants [26,27] . In the first step, linear alkyl amines with varying lengths (6‐12 carbons) were introduced via reductive amination using Pd/C, H 2 in ethanol.…”

“…The surfactants could be obtained after filtration and freeze‐drying, in good yields (86 %–98 %). The yields were significantly lower when the reaction was performed with NaBH 4 as a reducing agent [27] . Next, we utilized the obtained tertiary amine‐containing compounds (Scheme 2, II) to synthesize N ‐oxide‐based surfactants through an N ‐oxidation reaction (Table 1).…”

Reductive Aminomethylation Using Ammonium Formate and Methanol as N1 and C1 Source: Direct Synthesis of Mono- and Di-Methylated Amines

“…Among different organic reactions, catalytic reductive amination represents a convenient and common methodology for the synthesis and functionalization of amines, widely applied in both academic and industrial-level research. − It plays a paramount role in C–N bond construction due to its synthetic merits such as operational simplicity and availability of a wide range of substrates and protocols. Although many literature reports are there for the reductive amination of carbonyl compounds for the synthesis of amines, most of the protocols require the use of hydrogen pressure or stoichiometric reducing agents, such as metal borohydrides, formic acid, boranes, and silanes, which are either difficult to handle or generate significant waste products. ,,− …”