Copper-Catalyzed Hiyama Coupling of (Hetero)aryltriethoxysilanes with (Hetero)aryl Iodides

Abstract

A Cu(I)-catalyzed Hiyama coupling was achieved, which proceeds in the absence of an ancillary ligand for aryl-heteroaryl and heteroaryl-heteroaryl couplings. A P,N-ligand is required to obtain the best product yields for aryl-aryl couplings. In addition to facilitating transmetalation, CsF is also found to function as a stabilizer of the [CuAr] species, potentially generated as an intermediate after transmetalation of aryltriethoxysilanes with Cu(I)-catalysts in the absence of ancillary ligands.

In Situ Generation of ArCu from CuF2 Makes Coupling of Bulky Aryl Silanes Feasible and Highly Efficient

“…There are also several studies of palladium‐free systems in which transmetalation between organosilanes and copper takes place, always in the presence of fluoride salts . The palladium‐free Hiyama reaction catalyzed by CuI, using CsF and P,N ligands, has been reported . However, chemical systems analogous to those mentioned above were, in our hands, inefficient for the cross‐coupling of ortho ‐disubstituted arylsilanes .…”

“…[21][22][23] The palladium-free Hiyama reaction catalyzed by CuI, using CsF andP ,N ligands, has been reported. [24] However, chemicals ystems analogoust ot hose mentioned above were, in our hands, inefficientf or the cross-couplingo fortho-disubstituteda rylsilanes. [25] Eventually,inamethodical testing of palladium/copper systems with different copper additives and fluorides ourcesf or the mesityl-aryl cross-coupling [Eq.…”

Well‐Defined Copper(I) Fluoroalkoxide Complexes for Trifluoroethoxylation of Aryl and Heteroaryl Bromides

“…[29] In summary,aseries of copper(I) fluoroalkoxide complexes supported by the phenanthroline ligand have been synthesized and structurally characterized. These results imply that the trifluoroethoxylation does not involve aryl radical intermediates.…”

Cu‐catalyzed coupling of arylsulfinic salts with arylsilanes under mild conditions

“…On the basis of previous work on copper‐catalyzed coupling with aryl silanes, which suggested that Cu(I)‐catalyzed sulfonylation with sodium arylsulfinate might proceed through a CuF species involved in a transmetalation pathway, a proposed mechanism is shown in Scheme . The copper catalyst may first react with sodium arylsulfinate to form the ArS(O)OCu reactive intermediate (Scheme , A), followed by combination with KF to produce the intermediate B.…”