1335558-23-0Relevant academic research and scientific papers
Copper-catalyzed cross-coupling of aryl- and heteroaryltriethoxysilanes with aryl and heteroaryl iodides and bromides
Gurung, Santosh K.,Thapa, Surendra,Shrestha, Bijay,Giri, Ramesh
, p. 1933 - 1937 (2014)
Copper(I)-catalyzed coupling of aryl- and heteroaryltriethoxysilanes with aryl and heteroaryl iodides is described. The transformation also proceeds with activated aryl bromides, but in this case it requires a stoichiometric amount of the catalyst for best product yields. The current reaction requires a P,N-based bidentate ligand for aryl-aryl coupling while it proceeds without external ligands for aryl-heteroaryl coupling to afford good product yields. The reaction protocol can also be applied to achieve biarylation of diiodoarenes in reasonable yields. Georg Thieme Verlag Stuttgart New York.
General copper-catalyzed coupling of alkyl-, aryl-, and alkynylaluminum reagents with organohalides
Shrestha, Bijay,Thapa, Surendra,Gurung, Santosh K.,Pike, Ryan A. S.,Giri, Ramesh
, p. 787 - 802 (2016/02/18)
We report the first example of a very general Cu-catalyzed cross-coupling of organoaluminum reagents with organohalides. The reactions proceed for the couplings of alkyl-, aryl-, and alkynylaluminum reagents with aryl and heteroaryl halides and vinyl bromides, affording the cross-coupled products in good to excellent yields. Both primary and secondary alkylaluminum reagents can be utilized as organometallic coupling partners. These reactions are not complicated by β-hydride elimination, and as a result rearranged products are not observed with secondary alkylaluminum reagents even for couplings with heteroaryl halides under "ligand-free" conditions. Radical clock experiment with a radical probe and relative reactivity study of Ph3Al with two haloarenes, 1-bromonaphthalene and 4-chlorobenzonitrile, having two different redox potentials indicates that the reaction does not involve free aryl radicals and radical anions as intermediates. These results combined with the result of the Hammett plot obtained by reacting Ph3Al with iodoarenes containing p-H, p-Me, p-F, and p-CF3 substituents, which shows a linear curve (R2 = 0.99) with a ρ value of +1.06, suggest that the current transformation follows an oxidative addition-reductive elimination pathway.
Ligand-Free Copper-Catalyzed Negishi Coupling of Alkyl-, Aryl-, and Alkynylzinc Reagents with Heteroaryl Iodides
Thapa, Surendra,Kafle, Arjun,Gurung, Santosh K.,Montoya, Adam,Riedel, Patrick,Giri, Ramesh
, p. 8236 - 8240 (2015/07/07)
Reported herein is an unprecedented ligand-free copper-catalyzed cross-coupling of alkyl-, aryl-, and alkynylzinc reagents with heteroaryl iodides. The reaction proceeds at room temperature for the coupling of primary, secondary, and tertiary alkylzinc reagents with heteroaryl iodides without rearrangement. An elevated temperature (100 C) is required for aryl-heteroaryl and alkynyl-heteroaryl couplings.
