Multipath Reactions between Intramolecularly Formed Oxazolium Salts and Nucleophiles

Alfred Hassner, Bilha Fischer

Research output: Contribution to journalArticlepeer-review

14 Scopus citations


Reaction of 2-(4′-bromobutyl)-5-ethoxyoxazole (1) with nucleophiles led either to SN2 substitution products or to products with a piperidine skeleton. The latter were shown to arise from an intramolecular ring closure to an oxazolium salt 7, which was faster in the presence of a catalytic amount of NaI and in a polar solvent and for which NMR evidence is presented. The further transformation of 7 to 3–6 apparently involves addition of nucelophiles to 7 to produce 4-oxazoline 8 which opens to azomethine ylide 9. Neutralization of the latter occurred either via a proton shift, an alkyl shift, or via trapping by a dipolarophile (electron poor or electron rich). FMO calculations explain the preferred regiochemistry observed during trapping of ylide 9b.

Original languageEnglish
Pages (from-to)3070-3075
Number of pages6
JournalJournal of Organic Chemistry
Issue number11
StatePublished - 1 May 1992


Dive into the research topics of 'Multipath Reactions between Intramolecularly Formed Oxazolium Salts and Nucleophiles'. Together they form a unique fingerprint.

Cite this