4-Phosphono-β-lactams are synthesized via a three-step sequence, including final formation of the C3-C4 bond through a phosphorus-stabilized carbanion. The chlorinated precursors can be synthesized via two different methods: a one-pot N-acylation of an aromatic imine followed by addition of a trialkyl phosphite or phosphonylation of a suitable imine followed by N-acylation in a separate reaction step. The former method was preferred because of the ease of the reaction and the good yields obtained.
4-膦酰基-β-内酰胺通过三步序列合成,其中包括通过
磷稳定的碳负离子形成C3-C4键。
氯化前体可以通过两种不同方法合成:一种是将芳香
亚胺进行N-酰化,然后加入三烷基
亚磷酸酯或通过先对合适
亚胺进行膦酰化再进行独立反应步骤中的N-酰化。前者方法更受欢迎,因为反应简便且产率高。