Abstract
The chlorozinc enolate of ethyl-[(2, 2,5,5-tetramethyl-1-aza-2,5-disila)cyclopentyl]-acetate was reacted with the ZnCl{2} complex of N-benzylidene-2-phenylglycine methyl ester in THF at -70 }o{C. After removal of the protecting silyl moiety (3S, 4S, @aR)-1-(methoxycarbonyl)(phenyl)methyl-3-amino-4-phenyl-2-azetidinone was obtained in 73% yield with >97% d.e.. By treatment with aqueous ammonia complete epimerization at the @a-position was
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