26361-23-9Relevant academic research and scientific papers
Efficient synthetic approach to substituted benzo[b]furans and benzo[b]thiophenes by iodine-promoted cyclization of enaminones
Labarrios, Ehecatl,Jerezano, Alberto,Jimenez, Fabiola,Del Carmen Cruz, Maria,Delgado, Francisco,Zepeda, L. Gerardo,Tamariz, Joaquin
, p. 954 - 971 (2014/08/05)
An efficient synthetic approach to the substituted benzo[b]furan and benzo[b]thiophene scaffolds by iodine-mediated cyclization of the corresponding enaminones is described. This protocol was applied to a large series of these latter precursors to afford the respective benzoheterocycles substituted at the C-2 position by a carbonyl group functionality. A study of the factors that control this process reveals that the reactivity depends on the presence of electron-donor groups in the aryl ring of the aryloxycarbonylic and arylthiocarbonylic moieties.
An efficient synthesis of benzofurans and their application in the preparation of natural products of the genus Calea
Del Carmen Cruz, María,Tamariz, Joaquín
, p. 10061 - 10072 (2007/10/03)
The intramolecular cyclization of the β-substituted olefins methyl 2-aryloxy-3-dimethylaminopropenoates 3a-3f catalyzed by Lewis acids leads to a short and novel synthesis of benzofurans 2a-2f. When the olefins 4-dimethylamino-3-aryloxy-3-buten-2-ones 4a-4f were used, the cyclization process was faster and provided the corresponding substituted 2-acetylbenzofurans 1a-1f. Among the latter, naturally occurring compounds calebertin (1a), caleprunin A (1b), and caleprunin B (1c) were prepared in good overall yields. These benzofurans were also obtained by direct treatment under MW irradiation of the precursors 1-aryloxypropan-2-ones 7a-7c with DMFDMA, followed by addition of the catalyst, resulting in a route that was one step shorter.
