title: Preparation of new nitrogen-bridged heterocycles. 55. Reinvestigation of the bromination/dehydrobromination of ethyl 3-[2-(methylthio)indolizin-3-yl]acrylate derivatives.
abstract: The bromination/dehydrobromination reactions of ethyl 3-[1-alkoxycarbonyl-2-(methylthio)indolizin-3-yl]acrylates were reinvestigated. Reactions of the title compounds with two equivalents of bromine, followed by heating of the resulting reaction mixture and then treatment with a base gave the unexpected dialkyl 7-bromothieno[2,3-b]indolizine-2,9-dicarboxylates, while similar reactions using benzyltrimethylammonium tribromide as a brominating agent afforded only non-brominated thieno[2,3-b]indolizine derivatives, which were converted to the corresponding 7-bromo derivatives upon further treatment with bromine.
authors.affiliation: Department of Chemistry and Material Engineering, Faculty of Engineering, Shinshu University, Tokyo, Japan. akakehi@gipwc.shinshu-u.ac.jp
authors.forename: Akikazu
authors.initials: A
authors.lastname: Kakehi
authors.forename: Suketaka
authors.initials: S
authors.lastname: Ito
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Suga
authors.forename: Yuhichi
authors.initials: Y
authors.lastname: Kobayashi
authors.forename: Peng
authors.initials: P
authors.lastname: Zuo
authors.forename: Ryozo
authors.initials: R
authors.lastname: Iriye
mesh_terms: D001952:Bridged-Ring Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D003461:Crystallography; D006571:Heterocyclic Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D007212:Indolizines / Q000737:chemistry*; D008958:Models, Molecular; D015394:Molecular Structure; D009584:Nitrogen / Q000737:chemistry*; D000644:Quaternary Ammonium Compounds / Q000737:chemistry*
chemical_list: D001952:Bridged-Ring Compounds; D006571:Heterocyclic Compounds; D007212:Indolizines; D000644:Quaternary Ammonium Compounds; C000168:benzyltrimethylammonium; D009584:Nitrogen