Influence of strain on chemical reactivity. Relative reactivity of torsionally strained double bonds in 1,3-dipolar cycloadditions

The absolute reaction rates of picryl azide addition in CHCl3 with cyclic olefins are measured via molecular mechanics calculations and their products identified to determine the relationship between chemical reactivity and strain. The conformational analysis of their zwitterionic intermediates allows for the establishment of the mechanism of formation. Results indicate that the strain involved in an olefin alters both reactivity and stereochemistry.