Simple and novel synthesis of 3-(thio)phosphoryl-β-lactams by radical cyclization
作者:Paweł Punda、Sławomir Makowiec
DOI:10.1039/c3nj00192j
日期:——
Radicalcyclization of phosphono-acetenamides promoted by manganese(III) acetate leads exclusively to the formation of 3-phosphoryl-β-lactams. The thiophosphoryl analogues were also prepared using this method. In particular, the presented protocol does not require the use of noble metals, while comparable methods do.
N-alkenyl acetoacetamides can be simply obtained in good yields by reaction of acetylketene, generated by thermolysis of 2,2,6-trimethyl-4H-1,3-dioxin-4-one in refluxing toluene, with imines possessing an α-hydrogen atom.
The condensation of hydratropaaldehyde with primary aliphatic amines yields imines and with primary aromatic amines yields enamines. The enamines as well as the imines tautomerize in solution to an imine-enamine-equilibrium, which depends on the nature of the substituent on the nitrogen. The enamines consist of a mixture of the cis-trans-isomers.
One-Step Formation of N-Alkenyl-malonamides and N-Alkenyl-thiomalonamides from Carbamoyl Meldrum's Acids
作者:Paweł Punda、Sławomir Makowiec
DOI:10.1080/00397911.2011.634082
日期:2013.5.15
Abstract A one-pot synthesis for the preparation of N-alkenyl-malonamides and N-alkenyl-thiomalonamides was developed. 5-[Hydroxy/mercapto(aryl/alkylamino)methylene]-2,2-dimethyl-1,3-dioxane-4,6-dione act as a source of ketenes that react with the tautomeric form of alkyl-(2-phenyl-propylidene)-amines. A possible [2 + 2] or [4 + 2] cycloaddition product of ketene to imines was not observed. GRAPHICAL