Oxidant-dependent Cu-catalyzed alkynylation and aminomethylation: C–H versus C–C cleavage in TMEDA

Oxidant-dependent Cu-catalyzed alkynylation and aminomethylation reactions have been achieved under facile and mild conditions. TMEDA coupled with various terminal alkynes via C–H bond cleavage in good yields using atmospheric oxygen as an oxidant. Switching from air to TBHP afforded aminomethylation products of terminal alkynes through C–C bond cleavage of TMEDA. The protocol provided a novel strategy to prepare bi/tridentate N-ligand.

Highly efficient alkynylation of TMEDA has been achieved under copper(II) catalysis for the first time. The chelation effect of diamines to copper was observed as the key factor to promoting this transformation. Meanwhile, TMEDA can act as an aminomethyl donor for aminomethylation of alkynes using TBHP as oxidant.Figure optionsDownload as PowerPoint slide