72093-43-7Relevant articles and documents
Palladium-Catalyzed Three-Component Coupling of Ynamides
Wakamatsu, Hideaki,Takahashi, Ayano,Ishii, Ayaka,Kikuchi, Youhei,Sasaki, Madoka,Saito, Yukako,Natori, Yoshihiro,Yoshimura, Yuichi
supporting information, p. 5299 - 5303 (2020/07/08)
A palladium-catalyzed regioselective three-component coupling of ynamides was developed. The reaction proceeded smoothly to furnish the desired products when carried out at 70 °C in acetonitrile/water with potassium carbonate in the presence of 2.5 mol percent Pd2(dba)3·CHCl3 without a ligand. Various iodides and boronic acids were used in this reaction, and a carbon-carbon bond was formed with satisfactory regioselectivity from the ynamides.
Oxidative Addition, Transmetalation, and Reductive Elimination at a 2,2′-Bipyridyl-Ligated Gold Center
Harper, Matthew J.,Arthur, Christopher J.,Crosby, John,Emmett, Edward J.,Falconer, Rosalyn L.,Fensham-Smith, Andrew J.,Gates, Paul J.,Leman, Thomas,McGrady, John E.,Bower, John F.,Russell, Christopher A.
, p. 4440 - 4445 (2018/04/05)
Three-coordinate bipyridyl complexes of gold, [(κ2-bipy)Au(η2-C2H4)][NTf2], are readily accessed by direct reaction of 2,2′-bipyridine (bipy), or its derivatives, with the homoleptic gold ethylene complex [Au(C2H4)3][NTf2]. The cheap and readily available bipyridyl ligands facilitate oxidative addition of aryl iodides to the Au(I) center to give [(κ2-bipy)Au(Ar)I][NTf2], which undergo first aryl-zinc transmetalation and second C-C reductive elimination to produce biaryl products. The products of each distinct step have been characterized. Computational techniques are used to probe the mechanism of the oxidative addition step, offering insight into both the origin of the reversibility of this process and the observation that electron-rich aryl iodides add faster than electron-poor substrates. Thus, for the first time, all steps that are characteristic of a conventional intermolecular Pd(0)-catalyzed biaryl synthesis are demonstrated from a common monometallic Au complex and in the absence of directing groups.
Mechanism insight and scope of PEPPSI-catalyzed cross-coupling reaction between triarylbismuth and arylbromide
Cassirame, Bénédicte,Condon, Sylvie,Pichon, Christophe
, p. 94 - 102 (2016/10/04)
In this paper we report the first cross-coupling reaction of Ar3Bi with Ar'X mediated by Pd-NHC complexes by keeping the ability of Ar3Bi to transfer the three aryl moieties. Investigations were carried out in order to minimize the quantity of the side product Ar-Ar coming from the conversion of Ar3Bi. The results showed that PEPPSI IPr was a good catalyst precursor. Efforts were focussed on the rule of each additive such as PPh3 and the base. It was notably found that the presence of PPh3 (ratio PEPPSI IPr/PPh3: 1/1) was essential to keep the process efficient. Therefore NHC-Pd-PPh3 has been assumed as being the catalytic species. Under the optimized reaction conditions the concomitant formation of the undesired biaryl side product was restricted to its inherent formation consecutive to the reduction of the catalyst precursor to Pd(0). In a last study, the scope and the limitation of the new catalytic methodology were examined and a large range of unsymmetrical biaryl compounds Ar-Ar’ bearing various substituents from strongly electron-donating to electron-withdrawing ones have been prepared and fully characterized.
