Asymmetric Synthesis of Diazepino-β-lactams by Cycloaddition of an 'Evans-Sjogren' Ketene with 1H-1,2-Diazepines

Article abstract of DOI:10.1002/hlca.19910740410

The ketene derivative of the chiral oxazolidone 1 underwent non-converted stereospecific <2 + 2> cycloadditions with the (Z)-imine moiety of diazepines 2, leading thereby with good diastereoselection to the trans-β-lactam adducts 3 (major) and 4 (minor).T