Synthesis of Amides with Remote Stereocenters by Catalytic Asymmetric γ‑Alkynylation of α,β-Unsaturated Amides

An iridium-catalyzed enantioselective
hydroalkynylation of α,β-unsaturated
amides was described. The selectivity of this reaction is distinct
from that observed in many catalytic hydroalkynylations of α,β-unsaturated
carbonyl compounds. It occurs selectively at the γ instead of
the β position. Preliminary mechanistic studies suggest that
the reaction proceeds through alkene isomerization followed by hydroalkynylation.
This method provides a straightforward route for the synthesis of
amides with a remote stereocenter at the γ position.