Transforming Methyl Levulinate into Biosurfactants and Biolubricants by Chemoselective Reductive Etherification with Fatty Alcohols

Abstract

Biomass‐derived surfactants with very good surface tension and critical micellar concentration properties were obtained by conversion of methyl levulinate into methyl 4‐alkoxypentanoates through reductive etherification with aliphatic alcohols. Among different bifunctional acid/metal catalysts best results were obtained with Pd on carbon bearing acid sites. The reaction occurred through the formation of an enol ether intermediate followed by hydrogenation. Pd in high‐density planes was the active hydrogenation species, and an optimum crystal size was found to be approximately 10 nm. The reductive etherification with aliphatic alcohols was extended to other aliphatic and cyclic ketones and aldehydes obtained from biomass, and excellent results were obtained on supported Pd catalysts with the reaction route and experimental conditions described in this work.

Catalytic Reductive Alcohol Etherifications with Carbonyl‐Based Compounds or CO2 and Related Transformations for the Synthesis of Ether Derivatives

“…For (hemi)acetals containing at least one α‐H, loss of water or R 1 OH generates the corresponding enol ether intermediate, in equilibrium with an oxocarbenium ion, which is easily reduced to the desired ether (path a). In the case of carbonyl compounds with no α‐H, (hemi)acetal intermediates might undergo a direct hydrogenolysis to the corresponding ether derivative (path b) [1g,38b–d,f,g,i] . It has also been suggested that direct hydrogenolysis, and/or related pathways, can entail the formation of an oxocarbenium ion intermediate by protonation of the (hemi)acetal and subsequent water/R 1 OH release, followed by its catalytic reduction to give the desired ether (path b’) [25a,38a,c,g,39] …”

Opportunities for the Use of Brazilian Biomass to Produce Renewable Chemicals and Materials

“…Levulinic acid has been used as an alternative fuel and as a reagent to produce chemicals such as γ‐valerolactone, succinic acid, butanone and 5‐nonanone [61–63] . In addition, methyl levulinate can be reacted with fatty alcohols in a reductive etherification process, in the presence of a Pd/C catalyst to synthesise biosurfactants and biolubricants [64] …”

“…[61][62][63] In addition, methyl levulinate can be reacted with fatty alcohols in a reductive etherification process, in the presence of a Pd/C catalyst to synthesise biosurfactants and biolubricants. [64]…”

Thieme‐IUPAC‐Preis:A. Li / Springer‐Preis für Heterocyclenchemie: C. D. Vanderwal / IACS‐Preise:X. Hu, A. Corma

“…Über Corma, Mitglied des Internationalen Beirats der Angewandten Chemie und Ehrenmitglied des Beirats von ChemCatChem , wurde hier zuletzt 2018 als Gewinner der Blaise‐Pascal‐Medaille in Chemie berichtet . Seine Gruppe stellte in ChemSusChem die Synthese von 5‐Hydroxymethylfurfural abgeleiteter Weichmacher und die Umwandlung von Lävulinsäuremethylester in biobasierte Tenside und Schmiermittel vor …”