The palladium(II)-catalyzedcarbocyclization of benzenecarbaldehydes with internal alkynes to afford 2,3-disubstituted indenones was reported. The annulation reaction proceeded through the transmetalation of Pd(II) with an aromatic aldehyde and the insertion of internal alkynes, followed by cyclization via the intramolecular nucleophilic addition of intermediate organopalladium(II) species to the aldehyde
报道了钯( II )催化的苯甲醛与内部炔烃的碳环化反应得到2,3-二取代茚酮。环化反应通过 Pd( II ) 与芳香醛的金属转移和内部炔烃的插入进行,然后通过中间有机钯( II ) 物质与醛基的分子内亲核加成环化。该反应以中等至良好的产率进行,具有高区域选择性。
Palladium-assisted formation of carbon-carbon bonds. Stoichiometric synthesis of indenols and indenones. Catalytic synthesis of an indenol
作者:José Vicente、José-Antonio Abad、Juan Gil-Rubio
DOI:10.1016/0022-328x(92)85036-v
日期:1992.9
Reactions of diphenylacetylene or dimethylacetylenedicarboxylate with Q2[Pd2R2Cl2(mu-Cl)2] (1) [Q = (PhCH2)Ph3P; R = 2,3,4-trimethoxy-6-formylphenyll give metallic palladium and 2,3-diphenyl-, or 2,3-dimethylcarboxylate-, 5,6,7-trimethoxyindenone (2 or 3). respectively whereas diphenylacetylene reacts with [PdR(bipy)(MeCN)]ClO4 (4), to give 2,3-diphenyl-5,6,7-trimethoxyindenol (5) and [Pd2 (OH)2(bipy)2](ClO4)2 (6). Catalytic synthesis of 5 is achieved by reaction of [HgR2], Ph2C2, and CuCl2 in the presence of (Me4N)2[Pd2Cl6] (molar ratios 1:2:2:0.1).