Tertiary Amine-Derived Ionic Liquid-Supported Squaramide as a Recyclable Organocatalyst for Noncovalent “On Water” Catalysis
作者:Rinat S. Tukhvatshin、Alexander S. Kucherenko、Yulia V. Nelyubina、Sergei G. Zlotin
DOI:10.1021/acscatal.7b00562
日期:2017.4.7
was synthesized from available precursors and applied as an efficient organocatalyst for asymmetricMichael additions of β-dicarbonyl compounds to α-nitroolefins in the presence of water. Corresponding Michael adducts were generated under proposed conditions in nearly quantitative yield with high enantioselectivity (up to 99% ee). Useful precursors to pharmaceutically important chiral β-amino acids and
homodinuclear Co2/aminophenol sulfonamide complex has been developed for the asymmetric Michaelreaction of β-ketoesters with nitroolefins. This procedure is capable of tolerating a wide range of substrates and excellent results (up to 99% yield, >99 : 1 dr and 98% ee) can also be obtained. Moreover, the reaction could be carried out on a 50 mmol scale without any decrease in the enantioselectivity