13425-76-8Relevant academic research and scientific papers
Synthesis of Furandicarboxylic Acid Esters From Nonfood Feedstocks Without Concomitant Levulinic Acid Formation
van der Klis, Frits,van Haveren, Jacco,van Es, Daan S.,Bitter, Johannes H.
, p. 1460 - 1468 (2017)
5-Hydroxymethylfurfural (HMF) is a versatile intermediate in biomass conversion pathways. However, the notoriously unstable nature of HMF imposes challenges to design selective routes to chemicals such as furan-2,5-dicarboxylic acid (FDCA). Here, a new strategy for obtaining furans is presented, bypassing the formation of the unstable HMF. Instead of starting with glucose/fructose and thus forming HMF as an intermediate, the new route starts from uronic acids, which are abundantly present in many agro residues such as sugar beet pulp, potato pulp, and citrus peels. Conversion of uronic acids, via ketoaldonic acids, to the intermediate formylfuroic acid (FFA) esters, and subsequently to FDCA esters, proceeds without formation of levulinic acid or insoluble humins. This new route provides an attractive strategy to valorize agricultural waste streams and a route to furanic building blocks without the co-production of levulinic acid or humins.
Regio- and stereo-selectivity in homogeneous catalytic hydrogenation of 2,5-diketo-D-threo-hexonic acid
Hamersak, Zdenko,Pavlovic, Nediljko,Delic, Vladimir,Sunjic, Vitomir
, p. 245 - 249 (1997)
2,5-Diketo-D-threo-hexonic acid (2,5-diketo-D-gluconic acid, 1), a crucial intermediate in the microbial production of L-threo-hex-2-enono-1,4-lactone (L-ascorbic acid, vitamin C), was isolated from the fermentation broth of bacterium Erwinia citreus ATCC 31623, and its regio- and stereo-selective hydrogenation, catalyzed by the water-soluble Ru(II) complex of tris(m-sulfophenyl)phosphine (TPPTS), was performed, The effect of hydrogen pressure, temperature, pH, and catalyst-to-substrate ratio on regio- and stereo-selectivity of the process was studied, at low pH, over 90% regioselectivity in favor of the reduction of the 5-keto group in 1 was achieved, affording L-xylo-2-hexulosonic acid (2-keto-L-gulonic acid, 2) as the main product. Maximal diastereoselectivity, i.e. ratio between 2 and 2-keto-n-gulonic acid (3) expressed as diastereomeric excess (d.e.%), amounted to ca. 50% and was not influenced by any of the above reaction parameters.
