Controlled photorelease of alkynoic acids and their decarboxylative deprotection for copper-catalyzed azide/alkyne cycloaddition.

A controlled photorelease of alkynoic acids from the meso-methyl BODIPY photoremovable protecting group facilitates their subsequent efficient decarboxylation to give terminal alkynes for a CuI-catalyzed azide/alkyne cycloaddition. The quantum efficiencies of the photochemical step and the kinetics of the click reaction step are reported.