INVESTIGADORES
IGUCHI Daniela
artículos
Título:
Formation of 2,2-dimethylchroman-4-ones during the photoinduced rearrangement of some aryl 3-methyl-2-butenoate esters. A mechanistic insight
Autor/es:
IGUCHI DANIELA; ERRA-BALSELLS ROSA; BONESI SERGIO M.
Revista:
TETRAHEDRON
Editorial:
PERGAMON-ELSEVIER SCIENCE LTD
Referencias:
Lugar: Amsterdam; Año: 2016 vol. 72 p. 1903 - 1910
ISSN:
0040-4020
Resumen:
Several aryl 3-methyl-2-butenoate esters upon irradiation lead to the formation of [1,3]-migrated photoproducts,phenol and, surprisingly 2,2-dimethylchroman-4-one derivatives. The starting photochemicalreaction takes place from the singlet excited state of the ester and as a total mechanism twoconsecutive reaction pathways are proposed. The former involves the photo-Fries rearrangement of theesters in all the solvents studied and, depending on the proticity of the solvent, the latter involves anESIPT process followed by thermal 6p-electrocyclic reaction and/or thermal (intramolecular oxa-Michaeladdition) cyclization of the ortho regioisomers photoformed. This second pathway is responsible of theformation of the 2,2-dimethylchroman-4-one derivatives.
