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Grignard and organocuprate reagents catalyze ring opening reactions of 3, 4-disubstituted N-BOC-beta-lactams to yield alpha,gamma-disubstituted beta-amino ketones. NMR analysis of the crude mixtures helps estimate the proportion of products generated in the reaction. Nature of Grignard reagents influences the reaction. The disubstituted ketones help synthesize alpha-amino acids and polyhydroxylated nitrogen-containing products.

Studies reveal that asymmetric 1, 4-addition of higher order silylcuprates to Oppolzer's N-enoylsultams is as diastereofacially selective as carbocupration of beta-silyl-substituted N-enoylsultams. Silylcupration efficiently yields enantiomerically pure beta-silyl carboxylic acid. H NMR spectroscopy yields the diastereomeric ratio for the addition reactions after flash chromatography of the initial reaction mixture.

A stereocontrolled synthetic route to racemic thienamycin precursors and beta-(hydroxymethyl)aspartic acid derivatives involves the formation of cis- and trans-3- 1'-(dimethylphenylsilyl)ethyl -4-alkoxycarbonyl beta-lactams. The beta-lactams result from the condensation of glyoxylic ester imines with acid chlorides (which leads to the cis-form) or with organocopper enolates (which leads to the trans-form), using the dimethylphenylsilyl group as a masked hydroxy function.