title: Novel synthesis of 2-(trifluoromethyl)- and 2-(perfluoroalkyl)-2-hydroxy-2H-chromenes and their regiospecific reaction with silyl enol ethers.
abstract: The synthesis of substituted 2-(trifluoromethyl)- and 2-(perfluoroalkyl)-2-hydroxy-2H-chromenes 2a-o was achieved in good yields by intramolecular cyclization of 3-(perfluoroalkyl)-3-phenoxypropenals 1 in the presence of aluminum chloride. Then a Lewis acid mediated nucleophilic reaction with silyl enol ethers 3 proceeded with complete regiospecificity to afford 4-functional 2-(trifluoromethyl)- and 2-(perfluoroalkyl)-4H-chromenes 4a-p with high yields.
authors.affiliation: Organisation Moléculaire, Evolution et Matériaux Fluorés, cc17, Université Montpellier II, UMR CNRS 5073, Place E. Bataillon, 34095 Montpellier Cedex 05, France.
authors.forename: Salem
authors.initials: S
authors.lastname: El Kharrat
authors.forename: Philippe
authors.initials: P
authors.lastname: Laurent
authors.forename: Hubert
authors.initials: H
authors.lastname: Blancou
mesh_terms: D001578:Benzopyrans / Q000138:chemical synthesis* / Q000737:chemistry*; D004987:Ethers / Q000737:chemistry*; D015394:Molecular Structure; D013237:Stereoisomerism; D014297:Trimethylsilyl Compounds / Q000737:chemistry*
chemical_list: D001578:Benzopyrans; D004987:Ethers; D014297:Trimethylsilyl Compounds