Copper-catalyzed multicomponent assembly of γ-butenolides <i>via</i> the interception of carbonyl ylides with iminium ions
作者:Mengchu Zhang、Sifan Yu、Ruyu Hua、Dan Zhang、Huang Qiu、Wenhao Hu
DOI:10.1039/d2ob02075k
日期:——
A Cu(I)-catalyzed three-componentreaction of cyclopropenes, enamines and aldehydes has been realized. This reaction proceeds via the interception of carbonyl oxonium ylide intermediates with α, β-unsaturated iminium ions that are in situ generated fromenamines and aldehydes under the catalysis of Cu(MeCN)4PF6, leading to the desired γ-butenolide derivatives in good yields and with moderate diastereoselectivities
Enantioenriched benzopyrano- and naphthopyrano-fused helical phosphafluorenes have been synthesized by the rhodium-catalyzed enantioselective double [2 + 2 + 2] cycloaddition of dialkynyl phosphorus compounds with phenol- or naphthol-linked tetraynes. Photophysical properties of these phosphafluorenes are also disclosed.