Palladium-catalyzed double arylations of terminal olefins in acetic acid
作者:Daichao Xu、Chunxin Lu、Wanzhi Chen
DOI:10.1016/j.tet.2011.12.017
日期:2012.2
A palladium-catalyzed Heck diarylation of terminalolefins under ligand-free conditions in acetic acid is described. This procedure allows double arylation of terminalolefins affording trisubstituted olefins in good to excellent yields. The methodology is applicable to the coupling of both electron-deficient and electron-rich aryl iodides leading to symmetrical and unsymmetrical β,β-diarylated alkenes
Palladium-catalyzed reactions of aryl iodides with trimethylsilylacetylenes and disubstituted alkynes: the synthesis of diarylacetylenes and triarylethylenes
trimethylsilylacetylene in the presence of 3 equiv. of sodiummethoxide and 5 mol% of Pd(PPh3)4 under refluxing methanol for 6 h gave diarylacetylene in good chemical yields. When the catalyst was replaced by Pd(dba)2 and 5 equiv. of aryl iodide were added under the same reaction conditions, triarylethylenes were obtained in 70–85% yields. Only the sterically hindered o-methoxyiodobenzene and 2-iodothiophene
(PhCl) was observed unexpectedly in the Pd-catalyzed cascade Sonogashira–hydroarylation reaction. This new type of carbon–carbonbond forming cross-coupling reaction was efficiently catalysed by Pd2(dba)3 in the presence of a catalytic amount of PhCl, which provides a facile and direct approach to the synthesis of trisubstituted olefins.
Palladium-catalyzed desulfitative hydroarylation of alkynes with sodium sulfinates
作者:Saiwen Liu、Yang Bai、Xiangxiang Cao、Fuhong Xiao、Guo-Jun Deng
DOI:10.1039/c3cc43723j
日期:——
A palladium-catalyzeddesulfitative hydroarylation of alkynes with arylsulfinicacid sodium salts is described. The reaction showed good regio- and stereoselectivity, and afforded the hydroarylation products in good yields. Various functional groups were well tolerated under the optimized reaction conditions.
Controlled mono- and double-Heck reaction catalyzed by a dicarbene dipalladium complex
作者:Yunfei Li、Gang Liu、Changsheng Cao、Shuzhan Wang、Yuling Li、Guangsheng Pang、Yanhui Shi
DOI:10.1016/j.tet.2013.05.030
日期:2013.7
phosphine-free mono- and double-Heck reaction of terminal olefins with electron-deficient and electron-rich aryl halides (iodides and bromides) is described. These reactions are catalyzed by the dicarbenedipalladiumcomplex 1 by controlling the stoichiometry of the aryl halide and the olefine, the loading of the palladium catalyst, as well as using different base, and with or without additive. The procedure