European Journal of Organic Chemistry,
Год журнала:
2023,
Номер
26(48)
Опубликована: Окт. 11, 2023
Abstract
N
‐Heterocyclic
carbene
(NHC)
catalyzed
radical‐radical
reactions
have
been
proven
to
be
powerful
strategies
for
assembling
ketyl‐containing
compounds
via
single
electron
transfer
(SET)
pathway
under
either
thermal
conditions
or
photoredox
conditions.
In
this
context,
acylation
of
alkenes
radical
relay
NHC‐organocatalysis
has
also
opened
a
new
window
the
difunctionalization
construct
valuable
molecules
in
organic
synthesis.
review,
advances
and
progress
were
summarized
according
different
ways
generation
key
NHC‐bound
ketyl‐type
radicals.
Furthermore,
reaction
scopes,
limitations
mechanisms
discussed
based
on
types
catalytic
systems.
Conclusions
perspectives
put
forward
at
end.
ACS Catalysis,
Год журнала:
2022,
Номер
12(19), С. 11984 - 11999
Опубликована: Сен. 19, 2022
Radical/radical
cross-coupling
reactions
represent
an
efficient
and
straightforward
approach
for
the
construction
of
chemical
bonds
accordingly
have
drawn
increasing
attention
over
past
decades.
In
order
to
achieve
synthetically
useful
transformations,
a
persistent
radical
should
be
coupled
with
transient
in
accordance
effect
(PRE).
However,
known
radicals
outnumber
by
far
types
free
radicals,
which
limits
widespread
application
PRE,
until
today.
Thus,
development
between
has
been
focus,
meanwhile
transition-metal
catalysis
successfully
implemented
artificially
prolong
lifetimes,
allowing
their
utilization
formal
radical/radical
cross-couplings.
Complementary
research
field
recently
uncovered
that
organocatalytically
generated
NHC-derived
ketyl
are
type
catalytically
radicals.
NHC-catalyzed
transformations
aldehydes
carboxylic
acid
derivatives
enabled
disclosure
ever-increasing
number
interesting
reactions,
different
from
traditional
ionic
processes,
offering
otherwise
inaccessible
activation
modes.
These
discoveries
opened
door
NHC
organocatalysis
manipulation
reactions.
Due
its
obvious
potential
synthetic
organic
chemistry,
it
is
timely
provide
perspective
on
this
emerging
field.
Chemical Science,
Год журнала:
2022,
Номер
13(29), С. 8491 - 8506
Опубликована: Янв. 1, 2022
Allenes
are
valuable
organic
molecules
that
feature
unique
physical
and
chemical
properties.
They
not
only
often
found
in
natural
products,
but
also
act
as
versatile
building
blocks
for
the
access
of
complex
molecular
targets,
such
pharmaceuticals,
functional
materials.
Therefore,
many
remarkable
elegant
methodologies
have
been
established
synthesis
allenes.
Recently,
more
methods
radical
allenes
developed,
clearly
emphasizing
associated
great
synthetic
values.
In
this
perspective,
we
will
discuss
recent
important
advances
ACS Catalysis,
Год журнала:
2024,
Номер
14(11), С. 8270 - 8293
Опубликована: Май 13, 2024
As
one
of
the
most
important
key
intermediates,
NHC-bound
acylazolium-based
ionic
transformations
have
been
intensively
explored
in
past
two
decades.
With
expeditious
development
NHC-catalyzed
radical
recent
years,
acylazolium
chemistry
has
reached
another
level,
with
number
relevant
publications
increasing
significantly.
However,
a
summary
focused
on
acylations
NHC-derived
acyl
azoliums
classified
according
to
mechanistic
difference
not
reported.
Such
detailed
classification
and
deep
analysis
provide
opportunities
for
better
understanding
history
trend
this
field.
In
review,
reactions
N-heterocyclic
carbene
(NHC)-derived
are
systematically
introduced.
The
achievements
challenges
within
area
also
summarized
discussed
at
end.
Nature Communications,
Год журнала:
2022,
Номер
13(1)
Опубликована: Авг. 26, 2022
Abstract
The
merger
of
photoredox
and
transition-metal
catalysis
has
evolved
as
a
robust
platform
in
organic
synthesis
over
the
past
decade.
stereoselective
1,4-functionalization
1,3-enynes,
prevalent
synthon
synthetic
chemistry,
could
afford
valuable
chiral
allene
derivatives.
However,
tremendous
efforts
have
been
focused
on
ionic
reaction
pathway.
radical-involved
asymmetric
1,3-enynes
remains
prominent
challenge.
Herein,
we
describe
three-component
1,4-dialkylation
via
dual
chromium
to
provide
allenols.
This
method
features
readily
available
starting
materials,
broad
substrate
scope,
good
functional
group
compatibility,
high
regioselectivity,
simultaneous
control
axial
central
chiralities.
Mechanistic
studies
suggest
that
this
proceeds
through
redox-neutral
Nature Communications,
Год журнала:
2022,
Номер
13(1)
Опубликована: Сен. 30, 2022
Three-component
carboacylation
of
simple
alkenes
with
readily
available
reagents
is
challenging.
Transition
metal-catalysed
intermolecular
works
for
strained
ring
or
directing
groups.
Herein,
we
develop
a
photoredox
cooperative
N-heterocyclic
carbene/Pd-catalysed
alkylacylation
aldehydes
and
unactivated
alkyl
halides
to
provide
ketones
in
good
yields.
This
multicomponent
coupling
reaction
features
wide
scope
alkenes,
broad
functional
group
compatibility
free
exogenous
photosensitizer
external
reductant.
In
addition,
series
chlorinated
cyclopropanes
one
two
vicinal
quaternary
carbons
obtained
when
chloroform
carbon
tetrachloride
used
as
the
halide.
The
involves
radicals
from
ketyl
under
carbene/Pd
catalysis.
Chemical Science,
Год журнала:
2023,
Номер
14(46), С. 13367 - 13383
Опубликована: Янв. 1, 2023
This
review
summarizes
recent
advances
in
combining
photo-
and
N-heterocyclic
carbene
catalysis,
as
well
provides
an
outlook
on
future
opportunities
challenges.
Angewandte Chemie International Edition,
Год журнала:
2023,
Номер
62(32)
Опубликована: Июнь 12, 2023
Considering
the
prevalence
of
alcohols
and
carboxylic
acids,
their
fragment
cross-coupling
reactions
could
hold
significant
implications
in
organic
synthesis.
Herein,
we
report
a
versatile
method
for
synthesizing
diverse
range
ketones
from
acid
derivatives
via
N-heterocyclic
carbene
(NHC)
catalysis.
Mechanistic
investigations
revealed
that
photoexcited
xanthates
acyl
azoliums
undergo
single
electron
transfer
(SET)
under
photocatalyst-free
conditions,
generating
NHC-derived
ketyl
radicals
alkyl
radicals.
These
open-shell
intermediates
subsequently
radical-radical
reaction,
yielding
valuable
ketones.
Furthermore,
this
approach
can
be
employed
three-component
involving
alkenes
enynes,
resulting
structurally
cross-coupled
The
unified
strategy
offers
unique
opportunity
coupling
derivatives,
accommodating
functional
groups
even
complex
settings.
