Photochemical Key Steps in the Synthesis of Surfactants from Furfural‐Derived Intermediates

Abstract

Furfural is oxidized to 2[5H]-furanone by using hydrogen peroxide or to 5-hydroxy-2[5H]-furanone by using photo-oxygenation. An amine function is introduced by photochemically induced radical addition of tertiairy amines, some of which carry an n-alkyl side chain as hydrophobic moiety. These amines are produced from fatty aldehydes and cyclic secondary amines. The resulting adducts are transformed into amphoteric surfactants possessing an ammonium and a carboxylate function. Amphoteric (pK(N) and isoelectric point) and surfactant properties such as the critical micelle concentration and the adsorption efficiency are determined.

Furfural: a renewable and versatile platform molecule for the synthesis of chemicals and fuels

“…14,444 The synthesis of surfactants has also been proposed. 445 As shown in the previous section, 5hydroxy-furan-2(5H)-one can be produced as a sub-product during the oxidation of FUR with H 2 O 2 . However, it can also be obtained by the photochemical oxidation of FUR in the presence of photosensitiser dyes such as rose Bengal or methylene blue that absorb in the visible light region.…”

“…However, it can also be obtained by the photochemical oxidation of FUR in the presence of photosensitiser dyes such as rose Bengal or methylene blue that absorb in the visible light region. 14,[444][445][446] It has been proposed that an endo-peroxide is initially formed by the reaction of FUR with the singlet oxygen generated during the photochemical sensitisation of O 2 ( Figure 34). This endo-peroxide is decarbonylated to afford the hydroxyfuranone.…”

Studies in organic and physical photochemistry – an interdisciplinary approach

“…A previously discussed, -aminoalkyl radical 176 is generated by a two-step hydrogen transfer forms the tertiary amine to the photochemical excited sensitizer (compare also bonds. 153,154 The addition of thiocarbamate 173 to nucleophilic radicals -aminoalkyl radicals 176 is less efficient. Nevertheless, a corresponding adduct 180 was also detected by mass spectroscopy.…”

Photochemically induced radical reactions with furanones

“…Further extension of the scope of the reaction was accomplished by influencing the steps of the radical chain mechanism. This was done by addition of thiocarbonyl compounds to the reaction mixture [60][61][62]. These compounds are able to add reversibly to radical intermediates [63,64].…”