Synthesis Of L-tert-lucine-derived Phase-Transfer Catalysts And Their Application To Asymmetric Nitro-Mannich Reaction

Two types of phase-transfer catalysts based on amino acid skeletons and some known catalysts were synthesized in this thesis.These phase-thansfer catalysts were applied to the asymmetric nitro-Mannich reaction of amino sulfone with aromatic nitroalkanes and asymmetric nitro-Mannich reaction of isatin-derived ketinines with nitromethane.This thesis was divided into the following three parts.1.We synthesized two types of phase transfer catalysts based on inexpensive L-tert-leucine.One was L-tert-leucine-derived double hydrogen bond phase-transfer catalysts,the other was L-tert-leucine-derived multi-hydrogen bond phase-transfer catalysts.2.We applied these two types of L-tert-leucine-derived phase-transfer catalysts to the asymmetric nitro-Mannich reaction of amino sulfone with aromatic nitroalkanes and got the corresponding products up to 97% yield,99% ee and 99:1 dr when the reaction was catalyzed by L-tert-leucine-derived double hydrogen bond phase-transfer catalysts.We obtained up to 99% yield,98% ee and 99:1 dr of products when the reaction was catalyzed by the L-tert-leucine-derived multi-hydrogen bond phase-transfer catalysts.At the same time,control experiments proved that the hydrogen bond and the quaternary ammonium had an important influence on the reactivity and stereoselectivity.3.We applied the L-tert-leucine-derived phase-transfer catalysts to the asymmetric nitro-Mannich reaction between isatin-derived ketimines and nitromethane.After conditions screening,the products showed good reactivity but the enantioselectivity was poor(49% ee).