Doyle–Kirmse Reaction on Alkynyl Hydrazone Carboxylates: Synthesis of 1,4-Allenyne and 1,5-Enyne Thioaryl Carboxylates

The first Doyle–Kirmse reaction
on alkynyl diazoacetates
using allyl/propargyl sulfides is reported. The development provides
diversified 1,5-enyne and 1,4-allenyne thioaryl carboxylates in good
yields under ligand-/additive-free AuCl and Rh2(OAc)4 catalysis, respectively (48 examples, up to 96% yield). The
study demonstrated the dual role of allyl sulfide as a ligand and
substrate. Also, we have exemplified various synthetic modifications
of the products to showcase the utility of different functional groups.