• Bulletin of the Korean Chemical Society
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• v.22 no.6
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• pp.553-558
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• 2001

A stereoselective synthesis of $1\beta-aminocarbapenems$ (11a-c) starting from-4-acetoxy-2-axetidinone derivative 4 is described. 4-Acetoxy-2-azetidinone derivative (4) was reacted with lithium enolate of benzophenone limine of glycine phenyl ester (5f) to give alkylated product (R)-6f in good yield with high diastereoselectivity. The alkylated procudt (R)-6f was transformed to thioesters (7a-c) by transesterification with thiols, Thioesters (7a-c) were converted to their oxalimides (8a-c), followed by the phosphite-mediated reductive cyclization to give carbapenems (9a-c). Removal of all protecting groups of carbapenems (9a-c) afforded $1\beta-aminocarbapenems$ (11a-c).