title: Conjugate addition of isocyanides to chromone 3-carboxylic acid: an efficient one-pot synthesis of chroman-4-one 2-carboxamides.
abstract: We report a novel Lewis acid catalysed tandem reaction of isocyanides, chromone 3-carboxylic acid and nucleophiles. An experimentally very simple procedure, involving the use of microwave irradiation in the presence of a Lewis acid catalyst, affords a representative collection of chromone-2-carboxamides and chromone-2-carboxamido-3-esters in high yields, in just a few minutes. Such an unprecedented strategy is formally equivalent to a conjugate addition of isocyanides to Michael acceptors.
authors.affiliation: Laboratorio de Química Orgánica y Bioorgánica, Dept Química Orgánica e Inorgánica, Facultad de Veterinaria, Universidad de Extremadura, 10071 Cáceres, Spain.
authors.forename: Ana G
authors.initials: AG
authors.lastname: Neo
authors.forename: Jesús
authors.initials: J
authors.lastname: Díaz
authors.forename: Stefano
authors.initials: S
authors.lastname: Marcaccini
authors.forename: Carlos F
authors.initials: CF
authors.lastname: Marcos
mesh_terms: D002264:Carboxylic Acids / Q000737:chemistry*; D060326:Chemistry Techniques, Synthetic / Q000379:methods*; D002839:Chromans / Q000138:chemical synthesis* / Q000737:chemistry*; D002867:Chromones / Q000737:chemistry*; D003486:Cyanides / Q000737:chemistry*; D005240:Feasibility Studies; D008958:Models, Molecular; D008968:Molecular Conformation
chemical_list: D002264:Carboxylic Acids; D002839:Chromans; D002867:Chromones; D003486:Cyanides