Stereospecific Synthesis of Highly Functionalized Tricyclic β-Lactams by Radical Cyclizations Using Titanocene Monochloride

Abstract

The reductive opening of epoxyimonobactams 1 with titanoncene (III) chloride gives rise to radicals that can be trapped by intramolecular pi systems (i.e., conjugated alkenes and lactone and amide carbonyls) in a stereospecific way to give new carbocyclic compounds such as tribactam 2.