60504-77-0Relevant 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.
A Systematic Study of Metal Triflates in Catalytic Transformations of Glucose in Water and Methanol: Identifying the Interplay of Br?nsted and Lewis Acidity
Bodachivskyi, Iurii,Kuzhiumparambil, Unnikrishnan,Williams, D. Bradley G.
, (2019/04/25)
The specific type of acidity associated with the given metal trifloromethanesulfonates (Br?nsted or Lewis acidity) dramatically influences the course of reactions, and it is possible to select for disaccharides, fructose, methyl glucosides, or methyl levulinate. Glucose is transformed into a range of value-added molecules in water and methanol under the action of acidic metal triflates as catalysts, including their analogous Br?nsted acid-assisted or Br?nsted base-modified systems. A systematic study is presented of a range of metal triflates in methanol and water, pinning down the preferred conditions to select for each product.
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.
