title: Microwave-Assisted Organocatalyzed Rearrangement of Propargyl Vinyl Ethers to Salicylaldehyde Derivatives: An Experimental and Theoretical Study.
abstract: The microwave-assisted imidazole-catalyzed transformation of propargyl vinyl ethers (PVEs) into multisubstituted salicylaldehydes is described. The reaction is instrumentally simple, scalable, and tolerates a diverse degree of substitution at the propargylic position of the starting PVE. The generated salicylaldehyde motifs incorporate a broad range of topologies, spanning from simple aromatic monocycles to complex fused polycyclic systems. The reaction is highly regioselective and takes place under symmetry-breaking conditions. The preparative power of this reaction was demonstrated in the first total synthesis of morintrifolin B, a benzophenone metabolite isolated from the small tree Morinda citrifolia L. A DFT study of the reaction was performed with full agreement between calculated values and experimental results. The theoretically calculated values support a domino mechanism comprising a propargyl Claisen rearrangement, a [1,3]-H shift, a [1,7]-H shift (enolization), a 6π electrocyclization, and an aromatization reaction.
authors.affiliation: Departamento de Química Biológica y Biotecnología, Instituto de Productos Naturales y Agrobiología, Consejo Superior de Investigaciones Científicas, Avenida Astrofísico Francisco Sánchez 3, 38206 La Laguna, Tenerife (Spain). fgarcia@ipna.csic.es.
authors.forename: David
authors.initials: D
authors.lastname: Tejedor
authors.affiliation: Departamento de Química Biológica y Biotecnología, Instituto de Productos Naturales y Agrobiología, Consejo Superior de Investigaciones Científicas, Avenida Astrofísico Francisco Sánchez 3, 38206 La Laguna, Tenerife (Spain).
authors.forename: Leandro
authors.initials: L
authors.lastname: Cotos
authors.affiliation: Departamento de Química Biológica y Biotecnología, Instituto de Productos Naturales y Agrobiología, Consejo Superior de Investigaciones Científicas, Avenida Astrofísico Francisco Sánchez 3, 38206 La Laguna, Tenerife (Spain).
authors.forename: Daniel
authors.initials: D
authors.lastname: Márquez-Arce
authors.affiliation: Facultad de Química, Universidad del País Vasco-Euskal Herriko Unibertsitatea (UPV/EHU) and Donostia International Physics Center (DIPC), P. K. 1072, San Sebastian-Donostia (Spain).
authors.forename: Mikel
authors.initials: M
authors.lastname: Odriozola-Gimeno
authors.affiliation: Facultad de Química, Universidad del País Vasco-Euskal Herriko Unibertsitatea (UPV/EHU) and Donostia International Physics Center (DIPC), P. K. 1072, San Sebastian-Donostia (Spain).|Ikerbasque, Basque Foundation for Science, María Díaz de Haro 3, 6°, 48013 Bilbao (Spain).
authors.forename: Miquel
authors.initials: M
authors.lastname: Torrent-Sucarrat
authors.affiliation: Facultad de Química, Universidad del País Vasco-Euskal Herriko Unibertsitatea (UPV/EHU) and Donostia International Physics Center (DIPC), P. K. 1072, San Sebastian-Donostia (Spain).
authors.forename: Fernando P
authors.initials: FP
authors.lastname: Cossío
authors.affiliation: Departamento de Química Biológica y Biotecnología, Instituto de Productos Naturales y Agrobiología, Consejo Superior de Investigaciones Científicas, Avenida Astrofísico Francisco Sánchez 3, 38206 La Laguna, Tenerife (Spain). dtejedor@ipna.csic.es.
authors.forename: Fernando
authors.initials: F
authors.lastname: García-Tellado
keywords: domino reactions; microwave chemistry; organocatalysis; synthetic methods; total synthesis