Base-promoted Conia-ene cyclization of propargyl amides
Organic & Biomolecular Chemistry,
Год журнала:
2023,
Номер
21(36), С. 7311 - 7315
Опубликована: Янв. 1, 2023
We
report
a
tBuOK-promoted
synthesis
of
1,3-dihydro-2H-pyrrol-2-one
and
4-methylenepyrrolidin-2-one
systems
via
Conia-ene
like
intramolecular
cyclization.
The
method
features
extremely
short
reaction
times
(5
min)
mild
conditions
(rt),
enabling
the
trapping
propargyl
unit
by
an
amide
enolate.
An
intriguing
anionic
chain
mechanism
is
at
work,
which
can
trigger
isomerization
exo-alkene
giving
access
to
otherwise
elusive
endo-product.
Язык: Английский
Intramolecular Cyclization of Alkynylheteroaromatic Substrates Bearing a Tethered Cyano Group: A Strategy for Accessing Fused Pyridoheterocycles
The Journal of Organic Chemistry,
Год журнала:
2023,
Номер
88(17), С. 12716 - 12726
Опубликована: Авг. 17, 2023
Heterocyclic
substrates
containing
a
conjugated
alkyne
and
pendant
nitrile
were
shown
to
cyclize
in
an
overall
tetradehydro-Diels–Alder
reaction
give
products
which
the
initial
heterocycle
bears
newly
fused
pyridine
ring.
Base-promoted
tautomerization
of
its
isomeric
allene
allows
this
process
occur
at
ambient
temperature.
DFT
studies
support
many
mechanistic
interpretations
results.
Язык: Английский