Kinetics of the Strain-Promoted Oxidation-Controlled Cycloalkyne-1,2-quinone Cycloaddition: Experimental and Theoretical Studies.

ABSTRACT: Stimulated by its success in both bioconjugation and surface modification, we studied the strain-promoted oxidation-controlled cycloalkyne-1,2-quinone cycloaddition (SPOCQ) in three ways. First, the second-order rate constants and activation parameters (ΔH^⧧) were determined of various cyclooctynes reacting with 4-tert-butyl-1,2-quinone in a SPOCQ reaction, yielding values for ΔH^⧧ of 4.5, 7.3, and 12.1 kcal/mol, for bicyclo[6.1.0]non-4-yne (BCN), cyclooctyne (OCT), and dibenzoazacyclooctyne (DIBAC), respectively. Second, their reaction paths were investigated in detail by a range of quantum mechanical calculations. Single-configuration theoretical methods, like various DFT and a range of MP2-based methods, typically overestimate this barrier by 3-8 kcal/mol (after incl

SUBMITTER: Escorihuela J 

PROVIDER: S-EPMC5759032 | biostudies-literature | 2018 Jan

REPOSITORIES: biostudies-literature