title: Bromoethylsulfonium salt--a more effective annulation agent for the synthesis of 6- and 7-membered 1,4-heterocyclic compounds.
abstract: Reaction of bromoethylsulfonium salt with 1,2-/1,3-aminoalcohols gave six- and seven-membered rings in good-to-excellent yields. The reactions proceed through generation of a vinyl sulfonium salt followed by annulation to give 1,4-heterocyclic compounds such as morpholines and benzoxazepines in a simple procedure. The method accommodates a range of nitrogen substituents and the amino alcohol can be substituted by amino thiols and diamines to give thiomorpholines, piperazines and benzodiazepines.
authors.affiliation: School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, United Kingdom.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Yar
authors.forename: Eoghan M
authors.initials: EM
authors.lastname: McGarrigle
authors.forename: Varinder K
authors.initials: VK
authors.lastname: Aggarwal
mesh_terms: D001381:Azepines / Q000138:chemical synthesis; D006571:Heterocyclic Compounds / Q000138:chemical synthesis*; D009025:Morpholines / Q000138:chemical synthesis; D012492:Salts / Q000737:chemistry; D013452:Sulfonium Compounds / Q000737:chemistry*
chemical_list: D001381:Azepines; D006571:Heterocyclic Compounds; D009025:Morpholines; D012492:Salts; D013452:Sulfonium Compounds; C037574:morpholine