1376702-19-0Relevant academic research and scientific papers
Asymmetric Oxy-Michael Addition to γ-Hydroxy-α,β-Unsaturated Carbonyls Using Formaldehyde as an Oxygen-Centered Nucleophile
Yoneda, Naoki,Hotta, Ayano,Asano, Keisuke,Matsubara, Seijiro
supporting information, p. 6264 - 6266 (2015/02/19)
Formaldehyde was utilized as an oxygen-centered nucleophile in an asymmetric oxy-Michael addition to γ-hydroxy-α,β-unsaturated carbonyl compounds using bifunctional organocatalysts through hemiacetal intermediates. The cyclic acetal product could be further transformed into β-hydroxycarbonyl compounds, useful synthetic intermediates leading to various important target molecules. As such, this method is an example of a novel formal asymmetric hydration of α,β-unsaturated carbonyl compounds.
Asymmetric synthesis of 1,3-oxazolidines via intramolecular aza-michael addition by bifunctional organocatalysts
Fukata, Yukihiro,Asano, Keisuke,Matsubara, Seijiro
supporting information, p. 355 - 357 (2013/05/09)
A novel synthetic route to optically active 1,3-oxazolidines via formal [3 + 2] cycloaddition in the presence of cinchonaalkaloid- thiourea-based bifunctional organocatalysts is reported. This protocol gives easy access to a wide range of chiral 1,3- oxazolidines. In addition, the results show that bifunctional organocatalysts can effect the intramolecular aza-Michael addition, leading to the asymmetric synthesis of nitrogencontaining heterocycles.
Procedure-controlled enantioselectivity switch in organocatalytic 2-oxazolidinone synthesis
Fukata, Yukihiro,Asano, Keisuke,Matsubara, Seijiro
supporting information, p. 12160 - 12163 (2013/09/23)
In a novel organocatalytic formal [3 + 2] cycloaddition to afford chiral 2-oxazolidinones, an enantioselectivity switch could be induced by changing the manner of addition of the reactants, even when the reaction components (cinchona-alkaloid-derived aminothiourea catalyst, substrates, and solvent) were the same.
Organocatalytic asymmetric oxy-Michael addition to a γ-hydroxy- α,β-unsaturated thioester via hemiacetal intermediates
Okamura, Takaaki,Asano, Keisuke,Matsubara, Seijiro
supporting information; experimental part, p. 5076 - 5078 (2012/07/02)
We report an asymmetric oxy-Michael addition to a γ-hydroxy-α, β-unsaturated thioester via hemiacetal intermediates in the presence of Cinchona-alkaloid-thiourea-based bifunctional organocatalysts. This method provides a novel enantioselective route to β-hydroxy carboxyl compounds, which in turn can be used to synthesize valuable chiral building blocks.
