Simple and novel synthesis of 3-(thio)phosphoryl-β-lactams by radical cyclization

Synthetic Methods for Azaheterocyclic Phosphonates and Their Biological Activity: An Update 2004–2024

“…This methodology is unfortunately limited to the use of N -arylimine substrates. Makowiec et al opted for the use of 5-phosphoryl-2,2-dimethyl-1,3-dioxane-4,6-diones for the thermal generation of ketenes to create a more widely applicable route toward 3-phosphono β-lactams . An unsuccessful synthesis of this compound led them toward the oxidation and radical cyclization of acetyl acetenamide derivatives, a reaction which had thus far not been considered for the preparation of 3-phosphoryl β-lactams ( 118 ).…”

A New Approach to the Synthesis of 4-Phosphonylated β-Lactams

“…7 In search for new biologically active β-lactams syntheses of their phosphonylated derivatives were also elaborated. Synthetic availability of substituted 3-phosphono-β-lactams is limited to three routes: the Staudinger reaction, [8][9][10][11][12] rhodium-catalyzed cyclization of α-diazo-α-(dialkoxyphosphoryl)acetamides thoroughly elaborated by Gois and coworkers, [13][14][15][16] and phosphonylation of N-substituted azetidin-2-ones. 17…”

Application of diethyl ethynephosphonate for the synthesis of 3-phosphonylated β-lactams via Kinugasa reaction

“…16 3-Phosphonylated β-lactams have never been prepared via Kinugasa reactions starting with diethyl ethynylphosphonate (4). Compound 4 has however been used extensively in [3+2]-cycloadditions with organic azides.…”