Detalhes bibliográficos
| Resumo: | Palladium or copper catalyzed aminations or amidations were performed to obtain diarylamines and diarylacetamides precursors of thienocarbazoles. The fact that an ortho-bromodiarylamine didn’t cyclize to the corresponding thienocarbazole under conditions known for carbazoles from ortho-halodiphenylamines, conducted us to a highgly efficient method of palladium-catalyzed intramolecular cyclisation with N-deprotection of ortho-halodiarylacetamides to thienocarbazoles. Other method of intramolecular cyclization of diarylamines based on the reoxidation of the Pd(0) formed by Cu(OAc)2 , avoiding the use of stoichiometric amounts of Pd(OAc)2, gave thienocarbazoles in a moderate yield, including a ring A methoxylated compound. An attempt to combine palladium and copper catalyses in a “one pot” reaction of amination and intramolecular cyclization gave as major product a N-benzo[b]thiophene substituted carbazole and the required thienocarbazole in low yield. |
| Autores principais: | Ferreira, Isabel C. F. R. |
| Outros Autores: | Queiroz, Maria João R. P.; Kirsch, G. |
| Assunto: | C-N coupling Copper Palladium Cyclization-deprotection Thienocarbazoles |
| Ano: | 2002 |
| País: | Portugal |
| Tipo de documento: | artigo |
| Tipo de acesso: | acesso aberto |
| Instituição associada: | Universidade do Minho |
| Idioma: | inglês |
| Origem: | RepositóriUM - Universidade do Minho |