Transition-Metal-Free O-, S-, and N-Arylation of Alcohols, Thiols, Amides, Amines, and Related Heterocycles

• Published in: Journal of organic chemistry 2011-01, Vol.76 (2), p.654-660
• Main Authors: Cano, Rafael, Ramón, Diego J, Yus, Miguel
• Format: Article
• Language: English
• Subjects: Alcohols - chemistry; Amides - chemistry; Amines - chemistry; Catalysis; Catalysts: preparations and properties; Chemistry; Exact sciences and technology; General and physical chemistry; Heterocyclic compounds; Heterocyclic Compounds - chemical synthesis; Heterocyclic Compounds - chemistry; Heterocyclic compounds with only one n hetero atom and condensed derivatives; Heterocyclic compounds with several n hetero atoms in the same ring, in separated rings or in fused rings; Magnetic Resonance Spectroscopy; Molecular Structure; Noncondensed benzenic compounds; Organic chemistry; Preparations and properties; Sulfhydryl Compounds - chemistry; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry; Transition Elements - chemistry
• ISSN: 0022-3263; 1520-6904
• DOI: 10.1021/jo1022052

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.