Abstract
The reaction of ketene with Schiff bases was investigated. Heating of ketene with Schiff bases (1a-l) without solvent gave α-unsubstituted β-lactams (2a-l). The reaction of ketene with ethyl N-furfurylideneglycinate (1k) to give the β-lactam 2k was carried out at various temperatures, and it was found that the yield of 2k was not much influenced by the reaction temperature. β-Lactams (2d, f, k, l) were treated with 10% aqueous sodium hydroxide in dioxane to give the corresponding carboxylic acids (4d, f, k, l) in good yields. Compounds 4d, f, l reacted with various amines in the presence of dicyclohexylcarbodiimide (DCC) to give the corresponding amides (5a-c, 8a-d).
