Abstract
Five N‐(4‐methoxyphenyl)‐ and five N‐(4‐ethoxyphenyl)‐β‐lactams were prepared by ketene‐imine [2+2] cycloaddition (Staudinger reaction). Then these 2‐azetidinones were N‐dearylated by grinding together with ceric ammonium nitrate without hazardous solvents in good to excellent yields. The solid‐solid phase N‐dearylation is easier, simpler, and more efficient than the general method in solution. The pure N‐unsubstituted β‐lactams obtained by a nontedious workup and without further purification.
Acknowledgment
The authors thank the Shiraz University Research Council for financial support (Grant No. 86‐GR‐SC‐23).