title: Preparation of new nitrogen-bridged heterocycles. 56. Syntheses and reactions of 1-[2,2-bis(alkylthio)-1-(ethoxycarbonylacetyl)vinyl]pyridinium salts.
abstract: The title compounds, readily available from the S-alkylation of pyridinium 1-[alkylthio(thiocarbonyl)](ethoxycarbonylacetyl)methylides with alkyl halides or alkyl bromoacetates, were treated with a base and then a dehydrogenating agent to provide some unique products such as 3-[bis(alkylthio)methylene]-2(3H)-indolizinones and dialkyl 7-methyl-4-oxo-1,4,8,8a-tetrahydro-1,4-thiazino[3,4,5-cd]indolizine-1,5-dicarboxylates. On the other hand, similar reaction of these pyridinium salts in the absence of the dehydrogenating agent afforded alkyl 2-hydroxyindlizine-3-carboxythiolates, whose yields were increased by adding trifluoroacetic acid to the reaction mixture. The structures of some products were confirmed by the X-ray analyses.
authors.affiliation: Department of Chemistry and Material Engineering, Faculty of Engineering, Shinshu University, 4-17-1 Wakasato, Nagano 380-8553, Japan. akakehi@gipwc.shinshu-u.ac.jp
authors.forename: Akikazu
authors.initials: A
authors.lastname: Kakehi
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Suga
authors.forename: Yuuya
authors.initials: Y
authors.lastname: Yamauchi
authors.forename: Katsuaki
authors.initials: K
authors.lastname: Yasuraoka
authors.forename: Tomoshige
authors.initials: T
authors.lastname: Kobayashi
authors.forename: Akira
authors.initials: A
authors.lastname: Ohta
mesh_terms: D006571:Heterocyclic Compounds / Q000138:chemical synthesis* / Q000378:metabolism; D017672:Nitrogen Compounds / Q000138:chemical synthesis* / Q000378:metabolism; D011726:Pyridinium Compounds / Q000138:chemical synthesis* / Q000378:metabolism; D012492:Salts / Q000138:chemical synthesis* / Q000378:metabolism
chemical_list: D006571:Heterocyclic Compounds; D017672:Nitrogen Compounds; D011726:Pyridinium Compounds; D012492:Salts