title: Determining the Origin of Rate-Independent Chemoselectivity in CuAAC Reactions: An Alkyne-Specific Shift in Rate-Determining Step.
abstract: We report a kinetic and spectroscopic analysis of alkyne-dependent chemoselectivity in the copper-catalyzed azide-alkyne click (CuAAC) reaction. Studies of six alkyne subtypes reveal that the rate-determining step (RDS) of an aromatic ynamine class is shifted from acetylide formation to the azide ligation/migratory insertion event allowing chemoselectivity independent of overall rate.
authors.affiliation: Department of Pure and Applied Chemistry, University of Strathclyde, Glasgow, G1 1XL, UK.
authors.forename: Ciaran P
authors.initials: CP
authors.lastname: Seath
authors.affiliation: Department of Pure and Applied Chemistry, University of Strathclyde, Glasgow, G1 1XL, UK.
authors.forename: Glenn A
authors.identifier: 0000-0002-4896-113X
authors.initials: GA
authors.lastname: Burley
authors.affiliation: Department of Pure and Applied Chemistry, University of Strathclyde, Glasgow, G1 1XL, UK.
authors.forename: Allan J B
authors.identifier: 0000-0002-1582-4286
authors.initials: AJ
authors.lastname: Watson
keywords: CuAAC; chemoselectivity; click reactions; reaction kinetics; ynamine