title: Intramolecular dehydro Diels-Alder reactions of diarylacetylenes: switching between benzo[b]- and benzo[c]fluorenones as products by controlling the rearrangement of cyclic allene intermediates.
abstract: Thermal cyclization of 1-[2-(arylethynyl)phenyl]-3-trimethylsilylpropynones affords a mixture of benzo[b]fluorenones and benzo[c]fluorenones. The ratio of the two isomers can be efficiently varied between 100:0 and 0:100 by introducing substituents with appropriate electronic and steric properties on the aryl rings and using an appropriate solvent.
authors.affiliation: Departamento de Química Orgánica y Unidad Asociada al CSIC, Facultad de Química, Universidad de Santiago de Compostela, 15782 Santiago de Compostela, Spain.
authors.forename: David
authors.initials: D
authors.lastname: Rodríguez
authors.forename: María Fernanda
authors.initials: MF
authors.lastname: Martínez-Esperón
authors.forename: Armando
authors.initials: A
authors.lastname: Navarro-Vázquez
authors.forename: Luis
authors.initials: L
authors.lastname: Castedo
authors.forename: Domingo
authors.initials: D
authors.lastname: Domínguez
authors.forename: Carlos
authors.initials: C
authors.lastname: Saá