NHC-stabilized gold(I) complexes: Suitable catalysts for 6-exo-dig heterocyclization of 1-(o-Ethynylaryl)ureas

Ana Gimeno, Mercedes Medio-Simón, Carmen Ramírez De Arellano, Gregorio Asensio, Ana B. Cuenca

Producción científica: Artículo en revista indizadaArtículorevisión exhaustiva

58 Citas (Scopus)

Resumen

Figure presented 3-substituted 1-(o-ethynylaryl)ureas 1 selectively undergo either 6-exo-dig or 5-endo-dig cyclization (to give 4-methylene-3,4-quinazolin- 2-ones 2 or indoles 3, respectively) depending on the choice of the metal, ligand, and reaction conditions. The best results (up to 96% yield) in the preparation of the hydroamination products 2 are achieved with the highly bulky NHC-stabilized cationic gold(I) complex [Au(IPr)]+. Conversely, ureas bearing an internal alkyne lead to the 5-endo-dig cyclization mode regardless of the gold(I) complex employed. Whereas the nature of the substituent at N-3 does not have any influence on the regiochemistry observed, it does, in some cases, affect the efficiency of these transformations.

Idioma originalInglés
Páginas (desde-hasta)1900-1903
Número de páginas4
PublicaciónOrganic Letters
Volumen12
N.º9
DOI
EstadoPublicada - 7 may 2010
Publicado de forma externa

Huella

Profundice en los temas de investigación de 'NHC-stabilized gold(I) complexes: Suitable catalysts for 6-exo-dig heterocyclization of 1-(o-Ethynylaryl)ureas'. En conjunto forman una huella única.

Citar esto