title: Microwave- and photoirradiation-induced staudinger reactions of cyclic imines and ketenes generated from alpha-diazoketones. A further investigation into the stereochemical process.
abstract: Reactions of ketenes generated from alpha-diazoketones with a series of acyclic and cyclic imines were investigated under both microwave and photoirradiation conditions. The results indicate that the zwitterionic azabutadiene-type intermediates yielded from imines and ketenes undergo a conrotatory ring closure exclusively to produce beta-lactams. It is notable that no Woodward-Hoffmann product was found under the ultraviolet irradiation. The photoirradiation-induced Staudinger reaction shows a different stereoselectivity from the electrocyclic reaction of substituted 1,3-butadiene.
authors.affiliation: Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Department of Chemical Biology, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, P. R. China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Liang
authors.forename: Lei
authors.initials: L
authors.lastname: Jiao
authors.forename: Shiwei
authors.initials: S
authors.lastname: Zhang
authors.forename: Jiaxi
authors.initials: J
authors.lastname: Xu
mesh_terms: D001391:Azo Compounds / Q000737:chemistry*; D002384:Catalysis; D007097:Imines / Q000737:chemistry* / Q000528:radiation effects; D007659:Ketones / Q000737:chemistry* / Q000528:radiation effects; D008872:Microwaves; D013237:Stereoisomerism; D047090:beta-Lactams / Q000138:chemical synthesis*
chemical_list: D001391:Azo Compounds; D007097:Imines; D007659:Ketones; D047090:beta-Lactams