title: Expedient synthesis of α-(2-azaheteroaryl) acetates via the addition of silyl ketene acetals to azine-N-oxides.
abstract: A new and expedient synthesis of α-(2-azaheteroaryl) acetates is presented. The reaction proceeds rapidly under mild conditions via the addition of silyl ketene acetals to azine-N-oxides in the presence of the phosphonium salt PyBroP. This procedure affords diverse α-(2-azaheteroaryl) acetates which are highly desirable components/building blocks in molecules of pharmaceutical interest but are traditionally challenging to synthesize via contemporary methods. The reaction optimization and mechanism as well as a novel electronically enhanced PyBroP derivative are described.
authors.affiliation: Pfizer Worldwide Medicinal Chemistry, Eastern Point Road, Groton, Connecticut 06340, United States.
authors.forename: Allyn T
authors.initials: AT
authors.lastname: Londregan
authors.forename: Kristen
authors.initials: K
authors.lastname: Burford
authors.forename: Edward L
authors.initials: EL
authors.lastname: Conn
authors.forename: Kevin D
authors.initials: KD
authors.lastname: Hesp
mesh_terms: D000080:Acetals / Q000138:chemical synthesis* / Q000737:chemistry; D000085:Acetates / Q000138:chemical synthesis* / Q000737:chemistry; D001372:Aza Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D005030:Ethylenes / Q000737:chemistry*; D007659:Ketones / Q000737:chemistry*; D015394:Molecular Structure; D009943:Organophosphorus Compounds / Q000737:chemistry*; D010087:Oxides / Q000737:chemistry*; D012821:Silanes / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D000080:Acetals; D000085:Acetates; D001372:Aza Compounds; D005030:Ethylenes; D007659:Ketones; D009943:Organophosphorus Compounds; D010087:Oxides; D012821:Silanes; C008223:ketene