Fig. 6: Mechanistic Studies.

a Possible intermediates. b The Hammett plot of the alkyne substrate. c Kinetic studies (inverse first order dependence for the BCB 1a and first order for both the alkyne 2 and the catalyst 108).

a Possible intermediates. b The Hammett plot of the alkyne substrate. c Kinetic studies (inverse first order dependence for the BCB 1a and first order for both the alkyne 2 and the catalyst 108).