Recently we have focused in the problem of preparation of carbamoylo-β-lactams as a result of oxidative cyclization of malonyl enamides. In our experiments we obtain mixture of two main β-lactam products: as a result of subsequent elimination and a second as a product of substitution. All of the produced β-lactams have trans configuration what was confirmed by 1H coupling constants. However id should be stressed that in the case of substitution product, a new chiral center is generated, leading to formation of two pair of diastereoisomers.For elucidate their structures we used ROESY and NOESY experiments. Correlations between β-lactam protons and a methyl group allowed to assign structures of pairs of diastereisomers.
Authors
Additional information
- Category
- Inne
- Type
- supllement, wydanie specjalne, dodatek
- Language
- angielski
- Publication year
- 2011
