340771-38-2Relevant articles and documents
Palladium precatalysts containing meta-terarylphosphine ligands for expedient copper-free Sonogashira cross-coupling reactions
Yang, Yong,Lim, Joyce Fen Yan,Chew, Xinying,Robins, Edward G.,Johannes, Charles W.,Lim, Yee Hwee,Jong, Howard
, p. 3501 - 3506 (2015/07/01)
Three novel palladium complexes utilizing different variations of the evolutionary meta-terarylphosphine ligand, CyPhine, were developed. These air- and moisture-stable complexes, PdCl2L2 (L = CyPhine, CyPhine-CF3 and CyPhine-nBu), demonstrated exceptional broad-based performance and operational simplicity in the copper-free Sonogashira cross-coupling of challenging (hetero-)aryl chlorides and terminal alkynes. Modifications to the periphery of the ligand scaffold showed modest improvements in the reaction rate when more electron-donating substituents were incorporated, which hints at potential design upgrades in the future.
Synthesis of unsymmetrically disubstituted ethynes by the palladium/copper(I)-cocatalyzed sila-Sonogashira-Hagihara coupling reactions of alkynylsilanes with aryl iodides, bromides, and chlorides through a direct activation of a carbon-silicon bond
Nishihara, Yasushi,Inoue, Eiji,Noyori, Shintaro,Ogawa, Daisuke,Okada, Yoshiaki,Iwasaki, Masayuki,Takagi, Kentaro
experimental part, p. 4869 - 4881 (2012/08/08)
In this paper, we explore the copper/palladium-cocatalyzed cross-coupling reactions of 1-aryl-2-trimethylsilylethynes with aryl iodides, bromides, and chlorides as coupling partners, to furnish unsymmetrically disubstituted ethynes in moderate to excellent yields. Various aryl iodides were subjected to reaction under the optimized conditions with 5 mol % of Pd(PPh3) 2 and 50 mol % of CuCl. The steric properties of the aryl iodide proved more influential to the outcome of the cross-coupling reaction than electronic factors. In addition, we succeeded in synthesizing unsymmetrical diarylethynes using two different aryl iodides in one-pot. Furthermore, under the same reaction conditions with 10 mol % of PdCl2, 40 mol % of P(4-FC6H4)3, and 50 mol % of CuCl as catalyst, we succeeded in synthesizing unsymmetrical diarylethynes from various aryl bromides. Finally, we explored reactions with aryl chlorides and duly discovered that unsymmetrical diarylethynes were obtainable in moderate to good yields when 10 mol % of Pd(OAc)2, 10 mol % of (-)-DIOP, and 10 mol % of CuCl were used. These reactions proceed through a direct activation of a carbon-silicon bond in alkynylsilanes by CuCl to generate the corresponding alkynylcopper species via transmetalation from silicon to copper. Mechanistic investigations on the reaction of alkynylsilanes with aryl bromides confirmed that the trimethylsilyl bromide generated in situ retarded both transmetalation steps between CuCl and alkynylsilane, and between palladium(II) species formed by oxidative addition and alkynylcopper species.
Efficient iron/copper cocatalyzed alkynylation of aryl iodides with terminal alkynes
Huang, He,Jiang, Hualiang,Chen, Kaixian,Liu, Hong
supporting information; experimental part, p. 9061 - 9064 (2009/04/11)
(Equation Presented) We developed a highly efficient and practical protocol for the coupling of terminal alkynes with aryl iodides that is catalyzed by inexpensive and environmentally benign Fe/Cu. A broad spectrum of substrates can participate in the process effectively to produce desired products in good yields. The versatility, generality, low cost, and environmental friendliness, in combination with exceptionally high reaction rates, render this method particularly attractive for industrial applications.
