title: Transition-metal-free O-, S-, and N-arylation of alcohols, thiols, amides, amines, and related heterocycles.
abstract: A new protocol for the Ullmann-type arylation process of different aromatic heterocycles without any transition-metal catalyst, implying the use of a combination of an excess of potassium hydroxide and dimethyl sulfoxide, is described. The reaction can be performed between a broad range of starting nucleophiles including phenol, alcohols, amines, nitrogen-containing five-membered systems such as pyrazoles, imidazoles, and indoles, and amides with haloarenes, iodide and bromide derivatives giving the best results, the possible pathway involving the in situ generation of the corresponding benzyne intermediate. When the reaction was performed with 2-iodoaniline and either carboxamides or isothiocyanato derivatives, the corresponding benzoazole derivatives were obtained.
authors.affiliation: Instituto de Síntesis Orgánica and Departamento de Química Orgánica, Facultad de Ciencias, Universidad de Alicante, Apdo. 99, E-03080-Alicante, Spain.
authors.forename: Rafael
authors.initials: R
authors.lastname: Cano
authors.forename: Diego J
authors.initials: DJ
authors.lastname: Ramón
authors.forename: Miguel
authors.initials: M
authors.lastname: Yus
mesh_terms: D000438:Alcohols / Q000737:chemistry*; D000577:Amides / Q000737:chemistry*; D000588:Amines / Q000737:chemistry*; D002384:Catalysis; D006571:Heterocyclic Compounds / Q000138:chemical synthesis* / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D013438:Sulfhydryl Compounds / Q000737:chemistry*; D028561:Transition Elements / Q000737:chemistry*
chemical_list: D000438:Alcohols; D000577:Amides; D000588:Amines; D006571:Heterocyclic Compounds; D013438:Sulfhydryl Compounds; D028561:Transition Elements