title: Oxidative rearrangement of spiro cyclobutane cyclic aminals: efficient construction of bicyclic amidines.
abstract: A new rearrangement reaction of spirocyclic cyclobutane N-halo aminals is described. This process, promoted by treatment of the aminals with N-halosuccinimides (NXS, X = Br or Cl), efficiently produces bicyclic amidines by a pathway involving initial N-halogenation of one of the aminal nitrogens followed by cyclobutane ring expansion through 1,2-C-to-N migration with simultaneous N-X bond cleavage.
authors.affiliation: Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamada-oka, Suita, Osaka, 565-0871, Japan.
authors.forename: Kenichi
authors.initials: K
authors.lastname: Murai
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Komatsu
authors.forename: Ryu
authors.initials: R
authors.lastname: Nagao
authors.forename: Hiromichi
authors.initials: H
authors.lastname: Fujioka
mesh_terms: D000578:Amidines / Q000138:chemical synthesis*; D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000138:chemical synthesis*; D003500:Cyclization; D003503:Cyclobutanes / Q000737:chemistry*; D015394:Molecular Structure; D010084:Oxidation-Reduction; D013141:Spiro Compounds / Q000737:chemistry*
chemical_list: D000578:Amidines; D019086:Bridged Bicyclo Compounds, Heterocyclic; D003503:Cyclobutanes; D013141:Spiro Compounds