Synthesis of Multisubstituted Triphenylenes and Phenanthrenes by Cascade Reaction of <i>o</i>-Iodobiphenyls or (<i>Z</i>)-β-Halostyrenes with <i>o</i>-Bromobenzyl Alcohols through Two Sequential C–C Bond Formations Catalyzed by a Palladium Complex
bearing both nucleophilic and electrophilic substituents, for the facile synthesis of polycyclic aromatic hydrocarbons. A palladium/electron-deficient phosphine catalyst efficiently coupled o-iodobiphenyls or (Z)-β-halostyrenes with o-bromobenzyl alcohols to afford triphenylenes and phenanthrenes, respectively. The present cascade reaction proceeded through deacetonative cross-coupling and sequential intramolecular
Palladium-Catalyzed Annulation of <i>o</i>-Iodobiphenyls with <i>o</i>-Bromobenzyl Alcohols: Synthesis of Functionalized Triphenylenes via C–C and C–H Bond Cleavages
作者:Masayuki Iwasaki、Shohei Iino、Yasushi Nishihara
DOI:10.1021/ol4025869
日期:2013.10.18
Treatment of o-iodobiphenyls with abromobenzyl alcohols in the presence of cesium carbonate under palladium catalysis affords a series of highly substituted triphenylenes. The reaction involves two C-C bond formations and C-C and C-H bond cleavages. A combination of palladium and an electron-deficient phosphine ligand proves to be effective for both decarbonylative cross-coupling and intramolecular cyclization.