title: Synthesis of 2-Fluoro-1,4-benzoxazines and 2-Fluoro-1,4-benzoxazepin-5-ones by Exploring the Nucleophilic Vinylic Substitution (S(N)V) Reaction of gem-Difluoroenamides.
abstract: N-Benzoyl β,β-difluoroenamides and N-benzoyl fluoroynamides are novel structural units which have been explored as precursors in heterocyclic synthesis. The presence of two fluorine atoms at the β-position of the enamide moiety endows unique electrophilic reactivity. Treatment of these enamides with oxygen nucleophiles gives rise to a nucleophilic vinylic substitution (S(N)V) reaction, which was directed toward 2-fluoro-1,4-benzoxazines and 2-fluoro-1,4-benzoxazepin-5-ones. Furthermore, fluorinated ynamides, a new type of building block, were prepared in excellent yields for the first time. In this case, β-addition of nucleophiles across the triple bond is observed also.
authors.affiliation: Department of Sustainable Organic Chemistry and Technology, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, B-9000 Ghent, Belgium.
authors.forename: Tamara
authors.initials: T
authors.lastname: Meiresonne
authors.affiliation: Department of Sustainable Organic Chemistry and Technology, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, B-9000 Ghent, Belgium.
authors.forename: Guido
authors.initials: G
authors.lastname: Verniest
authors.affiliation: Department of Sustainable Organic Chemistry and Technology, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, B-9000 Ghent, Belgium.
authors.forename: Norbert
authors.initials: N
authors.lastname: De Kimpe
authors.affiliation: Department of Sustainable Organic Chemistry and Technology, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, B-9000 Ghent, Belgium.
authors.forename: Sven
authors.initials: S
authors.lastname: Mangelinckx
mesh_terms: D048588:Benzoxazines / Q000138:chemical synthesis* / Q000737:chemistry; D005461:Fluorine / Q000737:chemistry*; D015394:Molecular Structure; D055601:Organic Chemistry Phenomena; D010077:Oxazepines / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: D048588:Benzoxazines; D010077:Oxazepines; D005461:Fluorine