title: Straightforward synthesis of dihydrobenzo[a]fluorenes through Au(I)-catalyzed formal [3 + 3] cycloadditions.
abstract: Dihydrobenzo[a]fluorene derivatives have been prepared by a formal intramolecular [3 + 3] cycloaddition of o-alkynylstyrenes bearing a secondary alkyl group at the β-position of the styrene moiety. The process, catalyzed by a cationic gold(I) complex, involves a 1,2-hydride migration as the key step. 6,11-Dihydro-5H-benzo[a]fluorenes could be obtained from the initially generated 6,6a-dihydro-5H-benzo[a]fluorenes by subsequent heating of the reaction mixture under gold(I) or Brønsted acid catalysis or directly by conducting the reactions at high temperature.
authors.affiliation: Área de Química Orgánica, Departamento de Química, Facultad de Ciencias, Universidad de Burgos, Pza. Misael Bañuelos s/n, 09001-Burgos, Spain.
authors.forename: Patricia
authors.initials: P
authors.lastname: García-García
authors.forename: Muhammad A
authors.initials: MA
authors.lastname: Rashid
authors.forename: Ana M
authors.initials: AM
authors.lastname: Sanjuán
authors.forename: Manuel A
authors.initials: MA
authors.lastname: Fernández-Rodríguez
authors.forename: Roberto
authors.initials: R
authors.lastname: Sanz
mesh_terms: D000480:Alkynes / Q000737:chemistry; D002384:Catalysis; D061565:Cycloaddition Reaction; D005449:Fluorenes / Q000138:chemical synthesis* / Q000737:chemistry; D006046:Gold / Q000737:chemistry*; D015394:Molecular Structure; D013237:Stereoisomerism; D013343:Styrenes / Q000737:chemistry
chemical_list: D000480:Alkynes; D005449:Fluorenes; D013343:Styrenes; D006046:Gold