Terminal Alkyne Addition to Diazodicarboxylates: Synthesis of Hydrazide Linked Alkynes (Ynehydrazides)

Abstract

A new route to form C(sp)-N bonds has been developed via addition of in situ generated lithium acetylides to sterically hindered diazodicarboxylates. The reaction provides straightforward access to a previously unexplored ynehydrazide class of stable N-linked alkynes directly from commercially available precursors. Preliminary results show that alkynyl hydrazides are useful reagents for the selective installation of nitrogen functional groups and as precursors to pharmaceutically relevant heterocycles using metal catalyzed cycloadditions and condensations.