jo402015n_si_001.pdf (22.3 MB)
Tandem Blaise/retro-Blaise Reaction for the Nitrile-Mediated Regioselective Intermolecular Addition of Unstabilized Zinc Ester Enolates (Reformatsky Reagents) to 1‑Alkynes and 1,3-Enynes
journal contribution
posted on 2013-11-15, 00:00 authored by Ju Hyun Kim, Yu Sung Chun, Sang-gi LeeWe report the novel use of a nitrile
as a mediator to achieve the
regioselective intermolecular addition of unstabilized zinc ester
enolates (Reformatsky reagents) to 1-alkynes and 1,3-enynes. This
reaction is made possible by a reversible addition of enolates to
a nitrile (Blaise reaction), generating a zinc aza-enolate that, unlike
zinc ester enolates, can add intermolecularly to 1-alkynes and 1,3-enynes.
Subsequent removal of the nitrile through a retro-Blaise reaction
generates the targeted addition product. This method is combined with
a Diels–Alder reaction and subsequent oxidative aromatization,
providing a tandem one-pot de novo construction of α-arylated
alkanoates from Reformatsky reagents.