192220-12-5Relevant academic research and scientific papers
Nucleophilic addition of nitrones to ketones: Development of a new catalytic asymmetric nitrone-aldol reaction
Bogevig, Anders,Gothelf, Kurt V.,Jorgensen, Karl Anker
, p. 5652 - 5661 (2002)
A new organic reaction has been discovered in which nitrones react with carbonyl compounds in an aldol-type reaction to give functionalized β-hydroxynitrones. The α-carbon atom of the nitrone undergoes a nucleophilic addition reaction to electron-deficient ketones, such as α-ketoesters, α, β-diketones, and trifluoromethyl ketones, to afford the products in moderate to good yields. The scope and potential of the reaction have been investigated and developed. The reaction can also be catalyzed by secondary amines. The use of chiral cyclic amines, such as L-proline leads to optically active β-hydroxynitrones in moderate yield and with moderate to high enantiomeric excess. The reaction mechanism was studied by kinetic measurements, intermediate and product analysis, and determination of the absolute configuration of the product; based on these investigations a mechanism for the new reaction is proposed.
Catalysis through temporary intramolecularity: Mechanistic investigations on aldehyde-catalyzed cope-type hydroamination lead to the discovery of a more efficient tethering catalyst
Guimond, Nicolas,MacDonald, Melissa J.,Lemieux, Valerie,Beauchemin, Andre M.
supporting information, p. 16571 - 16577,7 (2020/09/15)
Mechanistic investigations on the aldehyde-catalyzed intermolecular hydroamination of allylic amines using N-alkylhydroxylamines are presented. Under the reaction conditions, the presence of a specific aldehyde catalyst allows formation of a mixed aminal intermediate, which permits intramolecular Cope-type hydroamination. The reaction was determined to be first-order in both the aldehyde catalyst (α-benzyloxyacetaldehyde) and the allylic amine. However, the reaction displays an inverse order behavior in benzylhydroxylamine, which reveals a significant off-cycle pathway and highlights the importance of an aldehyde catalyst that promotes a reversible aminal formation. Kinetic isotope effect experiments suggest that hydroamination is the rate-limiting step of this catalytic cycle. Overall, these results enabled the elaboration of a more accurate catalytic cycle and led to the development of a more efficient catalytic system for alkene hydroamination. The use of 5-10 mol % of paraformaldehyde proved more effective than the use of 20 mol % of α-benzyloxyacetaldehyde, leading to high yields of intermolecular hydroamination products within 24 h at 30 °C.
NITRONE COMPOUNDS PRODRUGS AND PHARMACEUTICAL COMPOSITIONS OF THE SAME TO TREAT HUMAN DISORDERS
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Page/Page column 53, (2008/06/13)
Disclosed are aryl, heteroaromatic and bicyclic aryl nitrone compounds and pharmaceutical compositions containing such derivatives. The disclosed compositions are useful for preventing and/or treating pain, neurodegenerative, autoimmune and inflammatory diseases or conditions in mammals.
A nitrone based route to polyhydroxylated lactams and piperidines: An expeditious synthesis of rac-Fagomine
Degiorgis,Lombardo,Trombini
, p. 1243 - 1245 (2007/10/03)
The synthetic versatility of tetrahydrofuro[2,3-d]isoxazol-5(2H)ones, obtained from TMSOTf-promoted addition of 2-trimethylsilyloxyfuran to nitrones, is demonstrated in a two-step reductive sequence to give the title compounds. The cycloadducts obtained from a glycolaldehyde derived nitrone are first reduced with DIBAH, then hydrogenolyzed in the presence of Pd(OH)2 to give polyhydroxylated piperidines, including rac-fagomine. Direct hydrogenolysis of the same cycloadducts gives an easy entry to polyhydroxylated lactams.
