Lanthanide‐catalyzed alkynyl exchange through C−C single‐bondcleavage assisted by a secondary amino group is reported. A lanthanide amido complex is proposed as a key intermediate, which undergoes unprecedented reversible β‐alkynyl elimination followed by alkynyl exchange and imine reinsertion. The in situ homo‐ and cross‐dimerization of the liberated alkyne can serve as an additional driving force
Regio- and Stereoselective Dimerization of Terminal Alkynes to Enynes in InCl<sub>3</sub>-NaBH<sub>4</sub>-MeCN System
作者:De-Yu Yang、Chun-Yan Wang、Hua Su
DOI:10.1055/s-2004-815428
日期:——
A novel method to prepare (E)-enynes is described in this paper. The InCl3-NaBH4-MeCN system showed high regio- and stereoselectivity for the dimerization of terminal alkynes to enynes.
Transition-Metal-Catalyzed Synthesis of 1,3-Diynes and Ynamides from 2-Bromo-1-iodoalkenes
作者:Zheng-Wang Chen、Jun Xue、Miao-Ting Luo、Yue-Lu Wen、Min Ye、Liang-Xian Liu
DOI:10.1055/s-0034-1378652
日期:——
Diynes and ynamides are important products in chemical synthesis. An efficient palladium-catalyzed homocoupling reaction of 2-bromo-1-iodoalkenes to give 1,3-diynes has been developed. The reactions are conducted under convenient conditions and provide products in moderate to excellent yields. Moreover, ynamides were synthesized from 2-bromo-1-iodoalkenes and carbamates, and it is noteworthy that this reaction is catalyzed by nanoparticulate copper(I) oxide to give ynamides in high yields.
Iridium(I) complex of chelating pyridine-2-thiolate ligand: Synthesis, reactivity, and application to the catalytic E-selective terminal alkyne dimerization via C–H activation
作者:Kenichi Ogata、Akinori Toyota
DOI:10.1016/j.jorganchem.2007.06.030
日期:2007.9
iridium(III) hydride complexes [IrH(SiMePh2)(η2-SNC5H4)(PPh3)2] (4), [IrH(O2CCH3)(η2-SNC5H4)(PPh3)2] (5), and [IrH(CC(p-tolyl))(η2-SNC5H4)(PPh3)2] (6), respectively. Complex 2 catalyzed dimerization of terminalalkynes leading to enynes (7) with high E-selectivity via C–H bond activation.