Cycloaddition of Strained Cyclic Alkenes and -Quinones: A Distortion/Interaction Analysis.

The chemistry of strained unsaturated cyclic compounds has experienced remarkable growth in recent years via the development of metal-free click reactions. Among these reactions, the cycloaddition of cyclopropenes and their analogues to -quinones has been established as a highly promising click reaction. The present work investigates the mechanism involved in the cycloaddition of strained dienes to -quinones and structural factors that would influence this reaction.

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

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.