A trans-iodo(III)etherification reaction
of ynamides
with benziodoxole triflate and alcohols is reported. Despite the sensitivity
of ynamides and enamides toward Brønsted acid, the reaction could
be successfully performed under carefully controlled conditions to
afford β-alkoxy-β-amido vinylbenziodoxoles in moderate
to good yields. The products could be subjected to a sequence of cross-coupling
via C–I(III) bond cleavage and electrophilic halogenation of
the resulting α-alkoxyenamides, allowing for the preparation
of densely functionalized esters