56-82-6Relevant articles and documents
Catalytic wet air oxidation of D-glucose by perovskite type oxides (Fe, Co, Mn) for the synthesis of value-added chemicals
Geobaldo, Francesco,Pirone, Raffaele,Russo, Nunzio,Scelfo, Simone
, (2022/03/15)
The conversion of common biomasses derived, as D-glucose, into value-added chemicals has received highest attention in the last few years. Among all processes, the catalytic wet air oxidation (CWAO) of derived biomasses using noble metal-based heterogeneo
Selective Reductive Dimerization of CO2into Glycolaldehyde
Zhang, Dan,Jarava-Barrera, Carlos,Bontemps, Sébastien
, p. 4568 - 4575 (2021/05/04)
The selective dimerization of CO2 into glycolaldehyde is achieved in a one-pot two-step process via formaldehyde as a key intermediate. The first step concerns the iron-catalyzed selective reduction of CO2 into formaldehyde via formation and controlled hydrolysis of a bis(boryl)acetal compound. The second step concerns the carbene-catalyzed C-C bond formation to afford glycolaldehyde. Both carbon atoms of glycolaldehyde arise from CO2 as proven by the labeling experiment with 13CO2. This hybrid organometallic/organic catalytic system employs mild conditions (1 atm of CO2, 25 to 80 °C in less than 3 h) and low catalytic loadings (1 and 2.5%, respectively). Glycolaldehyde is obtained in 53% overall yield. The appealing reactivity of glycolaldehyde is exemplified (i) in a dimerization process leading to C4 aldose compounds and (ii) in a tri-component Petasis-Borono-Mannich reaction generating C-N and C-C bonds in one process.
Tin, molybdenum and tin-molybdenum oxides: Influence of Lewis and Bronsted acid sites on xylose conversion
Meneghetti, Mario R.,Meneghetti, Simoni M. P.,Pryston, Dhara B. A.,da Silva Avelino, Débora Olimpio,dos Santos, Thatiane V.
, (2021/11/16)
In this study, tin oxide (SnO2), molybdenum oxide (MoO3) and a mixed oxide based on tin and molybdenum (respectively, Sn100, Mo100 and SnMo25, synthesized by the impregnation method) were applied in xylose conversion. The best results were obtained employing Mo100 and SnMo25. In the presence of SnMo25, after 0.5 h, xylose conversions of 39.5%, 34.1% and 63.4% were obtained, respectively, at 110, 130 and 150 °C. For Mo100, conversions of 49.6%, 71.8% and 85.3% were attained under the same reaction conditions, showing that Mo100 provided the best conversion results. However, with the use of this catalyst there was an increase in the amount of soluble and insoluble polymeric material. In terms of the soluble products formed from xylose, depending on the reaction condition were detected xylulose (X), lyxose (L) and furfural (FUR), glyceraldehyde (GL), pyruvaldehyde (PYR), glycoaldehyde (GLYC), dihydroxyacetone (DHA), lactic acid (AL), levulinic acid (LA) and acetic acid (AA). However, with the use of Sn100 or without a catalyst (systems with low conversions) there was mainly the formation of lyxose. The use of Mo100 and SnMo25 (systems which exhibit high acidity) leads mainly to isomerization, epimerization and dehydration reactions, as in the case of the retro-aldol pathway and furfural conversion, highlighting the importance of Lewis and Bronsted acid sites in relation to modulating the selectivity of the systems.