Ring Lithiation and Functionalization of Imidazol-2-ylidene-boranes
2011; American Chemical Society; Volume: 13; Issue: 22 Linguagem: Inglês
10.1021/ol202516c
ISSN1523-7060
AutoresAndrey Solovyev, Emmanuel Lacôte, Dennis P. Curran,
Tópico(s)Catalytic Cross-Coupling Reactions
ResumoN,N'-dialkyl and N,N'-diaryl imidazol-2-ylidene-boranes and trifluoroboranes are rapidly lithiated at C4 of the imidazole ring, and the resulting intermediates have been quenched with an assortment of electrophiles to provide ring-functionalized imidazol-2-ylidene-boranes. Further deprotonation and functionalization of C5 have been demonstrated. Deboronation of the products by treatment with triflic acid or iodine and then methanol opens a route to C4/C5 functionalized imidazolium salts and imidazol-2-ylidenes.
Referência(s)