Intermediate Control: Unlocking Hitherto Unknown Reactivity and Selectivity in N-Conjugated Allenes and Alkynes
Accounts of Chemical Research,
Год журнала:
2025,
Номер
58(2), С. 281 - 298
Опубликована: Янв. 3, 2025
ConspectusControlling
selectivity
through
manipulation
of
reaction
intermediates
remains
one
the
most
enduring
challenges
in
organic
chemistry,
providing
novel
solutions
for
selective
C-C
π-bond
functionalization.
This
approach,
guided
by
activation
principles,
provides
an
effective
method
functional
group
installation,
enabling
direct
synthesis
molecules
that
are
inaccessible
conventional
pathways.
In
particular,
functionalization
N-conjugated
allenes
and
alkynes
has
emerged
as
a
promising
research
focus,
driven
advances
controlling
reactive
strategies.
this
regard,
our
group,
alongside
others,
established
some
new
approaches
have
suitable
platform
functionalized
enamides.
Account
reviews
recent
developments
field,
highlighting
modes
reactivity
selectivity,
atom-economical
functionalizations,
strategies
regio-
stereocontrol,
while
mechanistic
insights
into
related
transformations.Our
study
is
systematically
organized
two
sections
based
on
substrate
type
chronological
progression.
first
section,
we
establish
allenamide-derived
intermediates,
both
allenamide-alkyne
(AA)
cross-coupling
few
electrophile-promoted
hydrofunctionalization
reactions.
The
unprecedented
Pd-catalyzed
achieved
neighboring
chelation,
with
phosphine
ligand
selection
outcome.
parallel,
functionalizations─including
haloalkynylation,
hydrooxycarbonylation,
hydrodifluoroalkylation,
intermolecular
hydroamination─are
strategic
electrophiles
or
their
precursors.Additionally,
findings
demonstrate
how
ynamides'
toward
nucleophiles,
controlled
activator
modulation,
expands
scope
accessible
transformations.
Key
include:
(1)
chemoselective
[2
+
2
2]
annulation
efficient
trapping
N-arylated
nitrilium
ynamides,
(2)
divergent
C-H
indole-derived
vinylogous
ynamides
metal
via
intramolecular
hydroarylation,
(3)
bromoalkynylation-enabled
migration
1,3-alkynyl
shift.The
final
section
explores
N-electron
polarization
1,3-enynes
enables
chemoselectivity
metal-free
inter-
couplings
indole
substrates.
Our
modulating
conjugation
within
enyne
skeleton─through
linear
cross
conjugation─can
pathways
control
product
selectivity.This
aims
to
stimulate
broader
intermediate-controlled
activated
π-systems.
Future
directions
include
advanced
design,
strategies,
deeper
studies
enable
rational
development.
Язык: Английский
Hydrogen-Bonding Network-Enabled Terminal Selective Heteroarylation of Allenamides in Hexafluoroisopropanol
Organic Letters,
Год журнала:
2025,
Номер
unknown
Опубликована: Фев. 21, 2025
Hexafluoroisopropanol
(HFIP)-mediated
terminal
selective
heteroarylation
of
allenamides
has
been
accomplished
through
H-bonding
network-enabled
substrate
activation
in
a
robust
fashion.
This
strategy
features
cascade
process
involving
sequential
nucleophilic
addition
followed
by
electrophilic
heteroaromatic
substitution
and
is
well
suited
for
late-stage
functionalization
complex
bioactive
molecules.
The
elucidation
the
underlying
mechanism
was
achieved
comprehensive
combination
several
control
experiments,
kinetic
studies,
isotopic
labeling
isolation
HFIP-allenamide
intermediate
adduct.
Язык: Английский
(3+2) Annulation of Donor–Acceptor Cyclopropanes with Difluoroenoxysilanes: Syntheses of gem-Difluorocyclopentenes via α,α-Difluoroketone Scaffolds
The Journal of Organic Chemistry,
Год журнала:
2025,
Номер
unknown
Опубликована: Март 27, 2025
Herein,
we
present
an
acid-
and
base-mediated
approach
for
ring
opening
of
donor-acceptor
cyclopropanes
(DACs)
followed
by
(3+2)
annulation,
yielding
biologically
relevant
gem-difluorinated
cyclopentenes
via
α,α-difluoroketone
scaffolds.
Fluorinated
rings
are
essential
building
blocks
in
drug
discovery
materials
research.
This
methodology
has
a
broad
substrate
scope,
is
scalable,
provides
practical
synthetic
route
to
obtain
value-added
fluorinated
compounds.
Язык: Английский