title: Isocyanide addition to pyridinium salts. Efficient entry into substituted nicotinonitrile derivatives.
abstract: The addition of isocyanides to pyridinium salts is studied. The process takes place efficiently when a carboxamido group is present in the 3 position of the pyridine ring. The outcome of the reaction involves the stabilization of the nitrilium intermediate by the amide, which suffers a mild dehydration, leading regioselectively to beta-cyano-gamma-carbamoyl-1,4-dihydropyridines. In this way, a variety of nicotinamide derivatives were carbamoylated. Extension to quinolinium, isoquinolinium, and N-acylpyridinium salts is also reported. [reaction: see text]
authors.affiliation: Institute for Research in Biomedicine, Barcelona Science Park, Josep Samitier 1-5, 08028 Barcelona, Spain.
authors.forename: Nana Aba O
authors.initials: NA
authors.lastname: Williams
authors.forename: Carme
authors.initials: C
authors.lastname: Masdeu
authors.forename: José Luis
authors.initials: JL
authors.lastname: Díaz
authors.forename: Rodolfo
authors.initials: R
authors.lastname: Lavilla
mesh_terms: D000577:Amides / Q000737:chemistry; D003486:Cyanides / Q000737:chemistry*; D009536:Niacinamide / Q000737:chemistry; D009539:Nicotinic Acids / Q000138:chemical synthesis*; D009570:Nitriles / Q000138:chemical synthesis*; D011726:Pyridinium Compounds / Q000138:chemical synthesis*; D011806:Quinolinium Compounds / Q000138:chemical synthesis; D013237:Stereoisomerism
chemical_list: D000577:Amides; D003486:Cyanides; D009539:Nicotinic Acids; D009570:Nitriles; D011726:Pyridinium Compounds; D011806:Quinolinium Compounds; D009536:Niacinamide