Abstract
Highly substituted unnatural α-amino esters, for example, ethyl 3-alkyl-4-(aryl or vinyl)-2-(N -4-methoxyphenylamine)pent-4-enoates were prepared in a regiocontrolled and diastereoselective manner via Pd(II)-catalyzed three-component coupling of boronic acids and allenes with ethyl iminoacetate relying on the umpolung of the traditional electrophilicity of mono-π-allylpalladium complexes. The 2-aminopent-4-enoates were subjected to N-allylation and intramolecular ring-closing metathesis to afford tetrahydropyridines featuring an α-amino ester group.
Key words
amino acids - allyl complexes - multicomponent reactions - umpolung - palladium
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