example of oxyamination of azlactones with oxaziridines was realized using a chiral bisguanidinium salt. Efficient catalytic asymmetric oxyamination and kinetic resolution of oxaziridines occurred simultaneously. Various chiral oxazolin-4-one derivatives with potential biological activity were obtained (up to 92% ee). Meanwhile, a series of optically pure oxaziridines were recovered with up to 99% ee and
A bifunctional squaramide-catalyzed reaction of azlactones and o-quinone methides in situ generatedfrom 2-(1-tosylalkyl)-phenols has been succesfully developed under basic condition, providing an efficient and mild access to chiral dihydrocoumarins...
An asymmetric inverse-electron-demandhetero-Diels-Alderreaction between o-quinone methides and azlactones to generate potentially pharmacological active dihydrocoumarins has been achieved efficiently by using a chiral N,N'-dioxide-Sc(III) complex as the catalyst. The desired products were obtained in high yields with excellent enantioselectivities and diastereoselectivities (up to 94% yield, 96%