title: The copper-catalysed Suzuki-Miyaura coupling of alkylboron reagents: disproportionation of anionic (alkyl)(alkoxy)borates to anionic dialkylborates prior to transmetalation.
abstract: We report the first example of Cu(I)-catalysed coupling of alkylboron reagents with aryl and heteroaryl iodides that affords products in good to excellent yields. Preliminary mechanistic studies with alkylborates indicate that the anionic (alkoxy)(alkyl)borates, generated from alkyllithium and alkoxyboron reagents, undergo disproportionation to anionic dialkylborates and that both anionic alkylborates are active for transmetalation to a Cu(I)-catalyst. Results from a radical clock experiment and the Hammett plot imply that the reaction likely proceeds via a non-radical pathway.
authors.affiliation: Department of Chemistry & Chemical Biology, The University of New Mexico, Albuquerque, NM 87131, USA. rgiri@unm.edu.
authors.forename: Prakash
authors.initials: P
authors.lastname: Basnet
authors.forename: Surendra
authors.initials: S
authors.lastname: Thapa
authors.forename: Diane A
authors.initials: DA
authors.lastname: Dickie
authors.forename: Ramesh
authors.initials: R
authors.lastname: Giri