956584-44-4Relevant academic research and scientific papers
Enantioselective formal [3+3] annulation for the direct construction of bicyclic skeletons with four stereogenic centers
Cao, Chun-Li,Sun, Xiu-Li,Kang, Yan-Biao,Tang, Yong
, p. 4151 - 4154 (2007)
An enantioselective formal [3+3] annulation reaction of cyclic ketones with enones has been developed. In the presence of 20 mol % of pyrrolidine-thiourea 1a or N-[pyrrolidin-2-ylmethyl)trifluoromethanesulfonamide 1i, the reactions afford bicyclo [3.3.1]
Multifunctional phosphoramide-(S)-prolinamide derivatives as efficient organocatalysts in asymmetric aldol and Michael reactions
Cruz-Hernández, Carlos,Landeros, José M.,Juaristi, Eusebio
supporting information, p. 5455 - 5465 (2019/04/05)
The synthesis and evaluation of three novel chiral organocatalysts derived from (S)-proline and containing a bis-amidophosphoryl amine fragment are reported. The structure and conformation of the new compounds were determined by NMR spectroscopy and X-ray crystallographic analysis. The present study represents an effort directed to enhance the performance of (S)-proline-derived organocatalysts in asymmetric aldol and Michael reactions by means of increased steric interactions arising from the incorporation of naphthyl moieties in the catalysts. In the event, the stereoselectivity achieved with naphthyl substituents turned out to be rather similar to that obtained with phenyl analogs. Nevertheless, the new organocatalysts exhibited rather good enantio- and diastereoselectivities in aldol reactions with various isatins and aryl carbaldehydes, affording products with up to 94?:?6 diastereomeric ratios and enantiomeric ratios as high as 95?:?5. Furthermore, products obtained from Michael addition reactions exhibited up to 96?:?4 diastereomeric ratios and enantiomeric ratios as high as 98?:?2.
Synthesis of a New N-Diaminophosphoryl-N'-[(2S)-2-pyrrolidinylmethyl]thiourea as a Chiral Organocatalyst for the Stereoselective Michael Addition of Cyclohexanone to Nitrostyrenes and Chalcones – Application in Cascade Processes for the Synthesis of Polyc
Cruz-Hernández, Carlos,Martínez-Martínez, Eduardo,Hernández-González, Perla E.,Juaristi, Eusebio
supporting information, p. 6890 - 6900 (2018/11/23)
A highly diastereoselective and enantioselective Michael addition of enolizable ketones such as cyclohexanone and acetophenone to a variety of substituted trans-?-nitrostyrenes and chalcones was catalyzed by a novel chiral and unsymmetrical thiourea as or
Highly Enantioselective Reactions of Cyclohexanone and β,γ-Unsaturated α-Keto Ester: The Tuning of Chemo-selectivities by Secondary and Primary Amine Catalysts
Wei, Jianwei,Guo, Wengang,Zhou, Xin,Du, Xin,Liu, Yan,Li, Can
supporting information, p. 985 - 990 (2016/02/18)
A series of of amphiphilic imidazole based secondary and primary amine catalysts were synthesized and shown to be very effective with an acid cocatalyst for the asymmetric reaction of cyclohexanone to β,γ-unsaturated α-keto ester. Interestingly, primary a
