Chemical Reviews,
Journal Year:
2024,
Volume and Issue:
unknown
Published: Dec. 12, 2024
Since
the
seminal
report
by
Adachi
and
co-workers
in
2012,
there
has
been
a
veritable
explosion
of
interest
design
thermally
activated
delayed
fluorescence
(TADF)
compounds,
particularly
as
emitters
for
organic
light-emitting
diodes
(OLEDs).
With
rapid
advancements
innovation
materials
design,
efficiencies
TADF
OLEDs
each
primary
color
points
well
white
devices
now
rival
those
state-of-the-art
phosphorescent
emitters.
Beyond
electroluminescent
devices,
compounds
have
also
found
increasing
utility
applications
numerous
related
fields,
from
photocatalysis,
to
sensing,
imaging
beyond.
Following
our
previous
review
2017
(
Journal of the American Chemical Society,
Journal Year:
2021,
Volume and Issue:
143(13), P. 4903 - 4909
Published: March 24, 2021
N-Heterocyclic
carbene
(NHC)
catalysis
has
emerged
as
a
versatile
tool
in
modern
synthetic
chemistry.
Further
increasing
the
complexity,
several
processes
have
been
introduced
that
proceed
via
dual
catalysis,
where
NHC
organocatalyst
operates
concert
with
second
catalytic
moiety,
significantly
enlarging
reaction
scope.
In
biological
transformations,
multiple
is
generally
used
to
access
complex
natural
products.
Guided
by
strategy,
triple
studied
recently,
three
different
modes
are
merged
single
process.
this
Communication,
direct
α-C–H
acylation
of
various
alkenes
aroyl
fluorides
using
NHC,
sulfinate,
and
photoredox
cooperative
reported.
The
method
allows
preparation
α-substituted
vinyl
ketones
moderate
high
yields
excellent
functional
group
tolerance.
Mechanistic
studies
reveal
these
cascades
through
sequential
radical
addition/coupling/elimination
contrast
known
operate
two
sets
interwoven
cycles,
process,
all
cycles
interwoven.
Nature Communications,
Journal Year:
2021,
Volume and Issue:
12(1)
Published: June 22, 2021
Abstract
There
have
been
significant
advancements
in
radical
reactions
using
organocatalysts
modern
organic
synthesis.
Recently,
NHC-catalyzed
initiated
by
single
electron
transfer
processes
actively
studied.
However,
the
reported
examples
limited
to
catalysis
mediated
alkyl
radicals.
In
this
article,
NHC
organocatalysis
aryl
radicals
has
achieved.
The
enolate
form
of
Breslow
intermediate
derived
from
an
aldehyde
and
thiazolium-type
presence
a
base
undergoes
iodide,
providing
radical.
catalytically
generated
could
be
exploited
as
arylating
reagent
for
relay-type
arylacylation
styrenes
hydrogen
atom
abstraction
α-amino
C(sp
3
)–H
acylation
secondary
amides.
Beilstein Journal of Organic Chemistry,
Journal Year:
2021,
Volume and Issue:
17, P. 771 - 799
Published: April 6, 2021
The
reversible,
weak
ground-state
aggregate
formed
by
dipole–dipole
interactions
between
an
electron
donor
and
acceptor
is
referred
to
as
electron-donor–acceptor
(EDA)
complex.
Generally,
upon
light
irradiation,
the
EDA
complex
turns
into
excited
state,
causing
transfer
give
radicals
initiate
subsequent
reactions.
Besides
external
energy
source,
reactions
involving
participation
of
complexes
are
mild,
obviating
transition
metal
catalysts
or
photosensitizers
in
majority
cases
line
with
theme
green
chemistry.
This
review
discusses
synthetic
concerned
well
mechanisms
that
have
been
shown
over
past
five
years.
Journal of the American Chemical Society,
Journal Year:
2022,
Volume and Issue:
144(16), P. 7072 - 7079
Published: March 22, 2022
The
2,3-dihydrobenzofuran
scaffold
is
widely
found
in
natural
products
and
biologically
active
compounds.
Herein,
dearomatizing
2,3-fluoroaroylation
of
benzofurans
with
aroyl
fluorides
as
bifunctional
reagents
to
access
2,3-difunctionalized
dihydrobenzofurans
reported.
reaction
that
occurs
by
cooperative
NHC/photoredox
catalysis
provides
3-aroyl-2-fluoro-2,3-dihydrobenzofurans
moderate
good
yield
high
diastereoselectivity.
Cascades
proceed
via
radical/radical
cross-coupling
a
benzofuran
radical
cation
generated
the
photoredox
cycle
neutral
ketyl
formed
through
NHC
cycle.
redox-neutral
transformation
exhibits
broad
substrate
scope
functional
group
compatibility.
With
anhydrides
reagents,
aroyloxyacylation
achieved
strategy
can
also
be
applied
Angewandte Chemie International Edition,
Journal Year:
2021,
Volume and Issue:
60(48), P. 25252 - 25257
Published: Sept. 28, 2021
Cyclopropanes
are
an
important
class
of
building
blocks
in
organic
synthesis.
Herein,
a
ring-opening/arylcarboxylation/acylation
cascade
reaction
for
the
1,3-difunctionalization
aryl
cyclopropanes
enabled
by
cooperative
NHC
and
organophotoredox
catalysis
is
reported.
The
works
on
monosubstituted
that
contrast
to
heavily
investigated
donor-acceptor
more
challenging
be
difunctionalized.
key
step
radical/radical
cross
coupling
benzylic
radical
generated
photoredox
cycle
with
ketyl
from
cycle.
transformation
features
metal-free
conditions
tolerates
diverse
range
functionalities.
Nature Communications,
Journal Year:
2022,
Volume and Issue:
13(1)
Published: May 23, 2022
The
carbene
and
photocatalyst
co-catalyzed
radical
coupling
of
acyl
electrophile
a
precursor
is
emerging
as
attractive
method
for
ketone
synthesis.
However,
previous
reports
mainly
limited
to
prefunctionalized
precursors
two-component
coupling.
Herein,
an
N-heterocyclic
catalyzed
decarboxylative
carboxylic
acids
imidazoles
disclosed,
in
which
the
are
directly
used
precursors.
could
also
be
generated
situ
by
reaction
acid
with
CDI
thus
furnishing
formally
two
acids.
In
addition,
successfully
extended
three-component
using
alkene
third
partner
via
relay
process.
mild
conditions,
operational
simplicity,
use
reacting
partners
make
our
powerful
strategy
construction
complex
ketones
from
readily
available
starting
materials,
late-stage
modification
natural
products
medicines.
ACS Catalysis,
Journal Year:
2022,
Volume and Issue:
12(13), P. 7804 - 7810
Published: June 16, 2022
A
visible-light-driven
silyl
radical
generation
method
from
silylboronates
has
been
developed.
The
activation
of
with
a
catalytic
amount
mild
base
promoted
the
single-electron
oxidation
process
to
form
radicals.
Facile
single
electron
transfer
for
borate
readily
occurred
without
hydrogen
atom
hydrosilane
in
presence
various
photoredox
catalysts.
Combining
this
protocol
radical-mediated
N-heterocyclic
carbene
catalysis
enabled
acylsilylation
alkenes
via
relay
generation.
Furthermore,
recent
advanced
methods
synthesis
significantly
improved
utility
process.
Chemical Science,
Journal Year:
2022,
Volume and Issue:
13(11), P. 3169 - 3175
Published: Jan. 1, 2022
The
modulation
of
selectivity
highly
reactive
carbon
radical
cross-coupling
for
the
construction
C-C
bonds
represents
a
challenging
task
in
organic
chemistry.
N-Heterocyclic
carbene
(NHC)
catalyzed
transformations
have
opened
new
avenue
acyl
With
this
method,
selective
an
with
alkyl
efficient
was
successfully
realized.
However,
reaction
radicals
vinyl
has
been
much
less
investigated.
We
herein
describe
NHC
and
visible
light-mediated
photoredox
co-catalyzed
1,4-sulfonylacylation
1,3-enynes,
providing
structurally
diversified
valuable
tetrasubstituted
allenyl
ketones.
Mechanistic
studies
indicated
that
ketyl
are
formed
from
aroyl
fluorides
via
oxidative
quenching
photocatalyst
excited
state,
generated
chemo-specific
sulfonyl
addition
to
finally,
key
provides
