Gold(I)-Catalyzed Asymmetric Aldol Reaction of N-Methoxy-N-methyl-.alpha.-isocyanoacetamide (.alpha.-Isocyano Weinreb Amide). An Efficient Synthesis of Optically Active .beta.-Hydroxy .alpha.-Amino Aldehydes and Ketones

1995 ◽  
Vol 60 (6) ◽  
pp. 1727-1732 ◽  
Author(s):  
Masaya Sawamura ◽  
Yuki Nakayama ◽  
Tomoki Kato ◽  
Yoshihiko Ito
Keyword(s):  
Aldol Reaction ◽  
Optically Active ◽  
Efficient Synthesis ◽  
Asymmetric Aldol ◽  
Amino Aldehydes ◽  
Weinreb Amide ◽  
Asymmetric Aldol Reaction ◽  
Aldehydes And Ketones

Chiral Silver Alkoxide Catalyzed Asymmetric Aldol Reaction of Alkenyl Esters with Isatins

Synlett ◽  
2021 ◽  
Author(s):  
Akira Yanagisawa ◽  
Aiko Kawada
Keyword(s):  
Aldol Reaction ◽  
Optically Active ◽  
Asymmetric Aldol ◽  
Asymmetric Aldol Reaction ◽  
High Yields

AbstractA catalytic enantioselective aldol reaction of alkenyl esters with isatins was achieved using a DM-BINAP·AgOTf complex as the chiral precatalyst and N,N-diisopropylethylamine as the base precatalyst in the presence of methanol or 2,2,2-trifluoroethanol. Optically active 3-alkylated 3-hydroxy-2-oxindoles having up to 98% ee were diastereoselectively obtained in moderate to high yields not only from cyclic alkenyl esters but also from acyclic ones through the in situ generated chiral silver enolates.

Asymmetric Aldol Reaction of Alkenyl Esters with α-Ketoesters Catalyzed by Chiral Tin Alkoxides

Synlett ◽  
2021 ◽  
Author(s):  
Akira Yanagisawa ◽  
Chika Uchiyama ◽  
Kotaro Takagi
Keyword(s):  
Sodium Methoxide ◽  
Aldol Reaction ◽  
Optically Active ◽  
Asymmetric Aldol ◽  
Asymmetric Aldol Reaction ◽  
Tertiary Carbon ◽  
High Yields

A catalytic enantioselective aldol reaction of alkenyl esters with α-ketoesters was achieved using an (R)-BINOL-derived chiral tin dibromide possessing a 4-t-butylphenyl group at 3- and 3’-positions as the chiral precatalyst in the presence of sodium methoxide and methanol. Optically active aldol products possessing a chiral tertiary carbon with up to 92% ee were diastereoselectively obtained in moderate to high yields not only from cyclic alkenyl esters but also from acyclic ones under the influence of the in situ generated chiral tin methoxide.

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