110271-85-7Relevant academic research and scientific papers
Use of lithium aryloxides as promoters for preparation of α-hydroxy acid esters
Petrus, Rafa?,Fa?at, Patryk,Sobota, Piotr
, p. 866 - 876 (2020)
In this work, a hexanuclear lithium compound, [Li6(MesalO)6] (1), supported by a chelating ligand, namely methyl salicylato (MesalOH), was used as a precursor for preparation of the monomeric lithium aryloxides [Li(MesalO)(MesalOH)] (2) and [Li(MesalO)(MeOH)2] (3) via reactions with MesalOH or MeOH. These aryloxides were characterized by single-crystal X-ray diffraction, and spectroscopic and other analytical methods. The diffusion-ordered 1H NMR measurements revealed the retention of solid-state structures of 1 and 2 in THF-d8 solution. Experimental data obtained for 3 showed its decomposition into compound 1 and free MeOH. Compound 1 generated from 3 was also used as a catalyst for the alcoholysis of l-lactide (l-LA) and glycolide (GA) for the preparation of α-hydroxy acid esters. We established that during methanolysis in the presence of 1, l-LA was selectively transformed into methyl (S,S)-O-lactyllactate (MeL2), and GA was converted to methyl glycolate (MeG1) and oligoglycolate esters MeGn (n = 2, 3, and 4).
Method for producing alpha - hydroxycarboxylate
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Page/Page column 15, (2010/02/11)
The present invention provides a process for more efficiently producing an α-hydroxycarboxylic acid ester wherein side reactions due to the α-hydroxycarboxylic acid ester are inhibited or prevented in comparison with prior art production processes. The invention provides a process for producing an α-hydroxycarboxylic acid ester comprising Steps 1 to 3: Step 1. reacting, in the presence of oxygen, (i) a 1,2-diol with a 1,2-diol or (ii) a 1,2-diol with an alcohol to obtain a reaction product containing an α-hydroxycarboxylic acid ester; Step 2. separating the α-hydroxycarboxylic acid ester from the reaction product obtained in Step 1 by distillation under reduced pressure; and Step 3. feeding Step 1 with a mixture obtained by partially or entirely removing water from the reaction product, wherein the mixture contains an unreacted 1,2-diol and/or alcohol.
Reactions of α-Hydroxy Carbonyl Compounds with Azodicarboxylates and Triphenylphosphine: Synthesis of α-N-Hydroxy Amino Acid Derivatives
Kolasa, Teodozyj,Miller, Marvin J.
, p. 4978 - 4984 (2007/10/02)
Reaction of aliphatic α-hydroxy esters with azodicarboxylates and triphenylphosphine in the presence of either CbzNHOCH2Ph or trOCNHOCH2Ph provides a direct route to protected α-N-hydroxy amino acids.Similar reactions with aromatic α-hydroxy carbonyl compounds and derivatives result in predominate oxidation to the corresponding α-oxo carbonyl derivatives.
