title: Nucleophilic ortho-allylation of pyrroles and pyrazoles: an accelerated Pummerer/thio-Claisen rearrangement sequence.
abstract: Arylsulfinyl groups direct the metal-free, regiospecific, nucleophilic ortho-allylation of pyrroles and pyrazoles. Mechanistic studies support the intermediacy of allylsulfonium salts that undergo facile thio-Claisen rearrangement onto the heterocyclic ring, giving products of coupling. The strategy has been adapted to allow regiospecific propargylation of the heterocyclic substrates.
authors.affiliation: School of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, UK.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Eberhart
authors.forename: Claudio
authors.initials: C
authors.lastname: Cicoira
authors.forename: David J
authors.initials: DJ
authors.lastname: Procter
mesh_terms: D000478:Alkylation; D002384:Catalysis; D006571:Heterocyclic Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D015394:Molecular Structure; D011720:Pyrazoles / Q000138:chemical synthesis* / Q000737:chemistry; D011758:Pyrroles / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism; D013438:Sulfhydryl Compounds / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: D006571:Heterocyclic Compounds; D011720:Pyrazoles; D011758:Pyrroles; D013438:Sulfhydryl Compounds