title: Efficient Pd-catalyzed allene synthesis from alkynes and aryl bromides through an intramolecular base-assisted deprotonation (iBAD) mechanism.
abstract: An optimized ligand-controlled palladium-catalyzed allene synthesis starting from alkynes and aryl bromides giving rise to allene products in a simple and direct manner is described. The methodology is performed in an inter- and intramolecular fashion with unprecedented scope and excellent yields. Based on mechanistic investigations and on DFT calculations, the role played by the carboxylic additive (i.e., PivOH) in controlling the selectivity of the reaction is discussed, allowing us to propose an intramolecular base-assisted deprotonation (iBAD) mechanism for this process.
authors.affiliation: Institut de Chimie et Biochimie Moléculaires et Supramoléculaires, CPE Lyon, 43 Boulevard du 11 Novembre 1918, 69622 Villeurbanne (France).
authors.forename: Natalie
authors.initials: N
authors.lastname: Nella
authors.forename: Evelyne
authors.initials: E
authors.lastname: Parker
authors.forename: Julien
authors.initials: J
authors.lastname: Hitce
authors.forename: Paolo
authors.initials: P
authors.lastname: Larini
authors.forename: Rodolphe
authors.initials: R
authors.lastname: Jazzar
authors.forename: Olivier
authors.initials: O
authors.lastname: Baudoin
mesh_terms: D000466:Alkadienes / Q000138:chemical synthesis / Q000737:chemistry*; D000480:Alkynes / Q000737:chemistry*; D001965:Bromides / Q000737:chemistry*; D002384:Catalysis; D008968:Molecular Conformation; D010084:Oxidation-Reduction; D010165:Palladium / Q000737:chemistry*; D013816:Thermodynamics
chemical_list: D000466:Alkadienes; D000480:Alkynes; D001965:Bromides; D010165:Palladium
keywords: Heck reaction; allenes; density functional calculations; palladium; reaction mechanisms