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).
研究了
乙烯酮与席夫碱的反应。将
乙烯酮与席夫碱(1a-l)在无溶剂条件下加热,得到了α-未取代的β-内酰胺(2a-l)。在不同温度下进行了
乙烯酮与乙基N-糠叉甘
氨酸盐(1k)反应生成β-内酰胺2k的研究,发现2k的产率受反应温度的影响不大。β-内酰胺(2d, f, k, l)在
二恶烷中用10%
氢氧化钠水溶液处理,以良好产率得到了相应的
羧酸(4d, f, k, l)。化合物4d, f, l在二环己基碳二
亚胺(
DCC)存在下与各种胺反应,得到了相应的酰胺(5a-c, 8a-d)。