1,2-Addition Reaction Of Isatin Or Aromatic Aldehyde Catalyzed By Organic Molecular

1.Synthesis of Some Chiral Catalysts Derived From Cinchona Alkaloids,L-Proline and Chiral1,1’-bi-2-Naphthol (BINOL).Asymmetric organocatalysis has become a powerful tool for the synthesis ofoptically active compounds. Herein we synthesized some classic organocatalystsaccording to the literatures such as cinchona alkaloid derived primary amines,bifunctional thioureas, cyclohexanediamine derived thioureas, L-proline derivedthioureas and chiral1,1’-bi-2-naphthol (BINOL)-derived phosphoric acids.Subsequently, we investigated some asymmetric1,2-additions especially in thepresence of these catalysts.2.Addition Reaction between Isatin and Phosphite Esterα-Hydroxy phosphonates are widely existed in natural products, and display a widespectrum of biological pharmacological activity. We found organic base could catalyzethe reaction of isatin with dialkyl phosphites via1,2-aldol reaction, furnishingα1-oxin-dole-α-hydroxyphosphonates in good yields.3.Aldol Reaction between Unsaturated Ketone and Isatin Catalysted byBifunctional Thiourea-baseThe3-hydroxyindolin-2-one structural cores with quaternary stereogenic centersare widely existed in natural products, and display invaluable biological andpharmacological activity.We found thiourea-modified cinchona alkaloids as bifunctional catalysts couldcatalyze the reaction of isatin with α, β-unsaturated ketone via cross aldol reaction,furnishing optically active3-hydroxyindolin-2-one in good yields, with highstereoselectivities (up to92%).4.Addition Reaction Between Diethylzinc and Benzaldehyde Catalysted byL-Proline-Derived Thiourea Chiral alcohols are important synthetic intermediates of natural products andpharmaceuticals. The addition of diethylzinc to aldehydes in the presence of catalyticamount of chiral ligands has come to be regarded as a important process to the synthesisof enantiomerically enriched alcohols. The key of this method is the design andsynthesis of chiral ligands and chiral catalysts of high catalytic activity. We synthesisseries of L-proline derived chiral thiourea, and apply it to the1,2-addition of diethylzincto aldehydes, furnishing chiral alcohols with good to excellent yields, albeit withmorderate enatioselectivity.