The limitation of the CuAAC "click" reaction with a 2-azidopyridine substrate, owing to its equilibrium with a tetrazole isomer, is exploited herein for its utility in the Glaser−Hay reaction. A catalytic combination of a 2-azidopyridine analogue, 4azido-5H-pyrrolo[3,2-d]pyrimidine, and CuI afforded homocoupled products of terminal alkynes, without any trace of triazole product, under mild conditions with a broad substrate scope. Emphasis on carbohydrate-based substrates appended to a propargylic group led to 1,3-diynes in good to excellent yields.

Multicomponent reactions (MCRs) using dienaminodioate with post-benzylic oxidative transformation mediated by DDQ that afforded a diverse array of products are described.