60504-79-2Relevant articles and documents
Synthesis of natural/13C-enriched D-tagatose from natural/13C-enriched D-fructose
Suchy, Mojmír,Charlton, Thomas A.,Ben, Robert N.,Shuhendler, Adam J.
, (2021/07/26)
A concise, easily scalable synthesis of a rare ketohexose, D-tagatose, was developed, that is compatible with the preparation of D-[UL-13C6]tagatose. Epimerization of the widely available and inexpensive ketohexose D-fructose at the C-4 position via an oxidation/reduction (Dess-Martin periodinane/NaBH4) was a key step in the synthesis. Overall, fully protected natural D-tagatose (3.21 g) was prepared from D-fructose (9 g) on a 50 mmol scale in 23% overall yield, after five steps and two chromatographic purifications. D-[UL-13C6]Tagatose (92 mg) was prepared from D-[UL-13C6]fructose (465 mg, 2.5 mmol) in 16% overall yield after six steps and four chromatographic purifications.
Tin Grafted on Modified Alumina-Catalyzed Isomerisation of Glucose to Fructose
Yatoo, Muhamad Aadil,Saravanamurugan, Shunmugavel
, (2019/06/28)
The present study focuses on designing a catalyst based on hot water treated alumina (Al2O3-HWT) for the conversion of glucose to fructose. The glucose isomerisation reactions are performed with tin incorporated on parent Al2O3 and Al2O3-HWT in methanol. 0.5 wt% Sn/Al2O3-HWT affords a combined yield of fructose and methylfructoside (30.4%) which is two-fold higher than that obtained with 0.5wt% Sn/Al2O3 (15.1%), implying the importance of hot water treatment of Al2O3. Al2O3-HWT shows a very broad peak centred around 3440 cm-1, which could be assigned to OH stretching band of gibbsite, γ-Al(OH)3 which significantly diminished after solid state ion-exchange with SnCl4.5H2O (0.5 wt% Sn/Al2O3-HWT). UV-Vis diffused reflectance spectrum of 0.5 wt% Sn/Al2O3-HWT displays a peak centered at 241 nm, which can be ascribed to the incorporation of tin into the alumina network. XRD patterns of 0.5, 3 and 5 wt% Sn/Al2O3-HWT show that no peak corresponding to SnO2 is formed. Importantly, 0.5wt% SnO2/Al2O3-HWT exhibits a low activity, giving 13.2% of the total yield of fructose and methylfructoside, respectively, compared to 0.5wt% Sn/Al2O3-HWT (30.4% fructose), signifying the role of incorporated tin into the alumina network.
Kinetic analysis of hexose conversion to methyl lactate by Sn-Beta: Effects of substrate masking and of water
Tosi, Irene,Riisager, Anders,Taarning, Esben,Jensen, Pernille Rose,Meier, Sebastian
, p. 2137 - 2145 (2018/05/04)
Simple sugars show promise as substrates for the formation of fuels and chemicals using heterogeneous catalysts in alcoholic solvents. Sn-Beta is a particularly well-suited catalyst for the cleavage, isomerization and dehydration of sugars into more valuable chemicals. In order to understand these processes and save resources and time by optimising them, kinetic and mechanistic analyses are helpful. Herein, we study substrate entry into the Sn-Beta-catalysed methyl lactate process using abundant hexose substrates. NMR spectroscopy is applied to show that the formation of methyl lactate occurs in two kinetic regimes for fructose, glucose and sucrose. The majority of methyl lactate is not formed from the substrate directly, but from methyl fructosides in a slow regime. At 160 °C, more than 40% of substrate carbon are masked (i.e. reversibly protected in situ) as methyl fructosides within a few minutes when using hydrothermally synthesised Sn-Beta, while more than 60% methyl fructosides can be produced within a few minutes using post-synthetically treated Sn-Beta. A significant fraction of the substrate is thus masked by rapid methyl fructoside formation prior to subsequent slow release of fructose. This release is the rate-limiting step in the Sn-Beta-catalysed methyl lactate process, but it can be accelerated by the addition of small amounts of water at the expense of the maximum methyl lactate yield.
