Nature Communications,
Год журнала:
2024,
Номер
15(1)
Опубликована: Фев. 16, 2024
Abstract
Photoexcitation
of
the
electron-donor-acceptor
complexes
have
been
an
effective
approach
to
achieve
radicals
by
triggering
electron
transfer.
However,
catalytic
version
complex
photoactivation
is
quite
underdeveloped
comparing
well-established
utilization
electronically
biased
partners.
In
this
work,
we
utilize
4-nitrophthalonitrile
as
acceptor
facilitate
efficient
π-stacking
with
electron-rich
aromatics
form
complex.
The
characterization
and
energy
profiles
on
cocrystal
1,3,5-trimethoxybenzene
disclose
that
transfer
highly
favorable
under
light
irradiation.
This
catalyst
can
be
efficiently
applied
in
benzylic
C−H
bond
developing
Giese
reaction
alkylanisoles
oxidation
benzyl
alcohols.
A
broad
scope
tolerated
a
mechanism
also
proposed.
Moreover,
corresponding
π-anion
interaction
potassium
formate
further
hydrocarboxylation
alkenes
efficiently.
Journal of the American Chemical Society,
Год журнала:
2021,
Номер
143(47), С. 19648 - 19654
Опубликована: Ноя. 18, 2021
The
installation
of
gem-difluoromethylene
groups
into
organic
structures
remains
a
daunting
synthetic
challenge
despite
their
attractive
structural,
physical,
and
biochemical
properties.
A
very
efficient
retrosynthetic
approach
would
be
the
functionalization
single
C–F
bond
from
trifluoromethyl
group.
Recent
advances
in
this
line
attack
have
enabled
activation
trifluoromethylarenes,
but
limit
accessible
motifs
to
only
benzylic
gem-difluorinated
scaffolds.
In
contrast,
trifluoroacetates
enable
use
as
bifunctional
synthon.
Herein,
we
report
photochemically
mediated
method
for
defluorinative
alkylation
commodity
feedstock:
ethyl
trifluoroacetate.
novel
mechanistic
was
identified
using
our
previously
developed
diaryl
ketone
HAT
catalyst
hydroalkylation
diverse
suite
alkenes.
Furthermore,
electrochemical
studies
revealed
that
more
challenging
radical
precursors,
namely
trifluoroacetamides,
could
also
functionalized
via
synergistic
Lewis
acid/photochemical
activation.
Finally,
concise
gem-difluoro
analogs
FDA-approved
pharmaceutical
compounds.
Chemical Science,
Год журнала:
2022,
Номер
13(19), С. 5659 - 5666
Опубликована: Янв. 1, 2022
General
photoactivation
of
EDA
complexes
between
arylsulfonium
salts
and
1,4-diazabicyclo[2.2.2]octane
was
discovered.
This
practical
mode
enables
the
generation
aryl
radicals
for
C–H
functionalization
arenes.
Journal of the American Chemical Society,
Год журнала:
2021,
Номер
143(33), С. 13022 - 13028
Опубликована: Авг. 12, 2021
Herein
we
disclose
a
new
photochemical
process
to
prepare
carboxylic
acids
from
formate
salts
and
alkenes.
This
redox-neutral
hydrocarboxylation
proceeds
in
high
yields
across
diverse
functionalized
alkene
substrates
with
excellent
regioselectivity.
operationally
simple
procedure
can
be
readily
scaled
batch
at
low
photocatalyst
loading
(0.01%
photocatalyst).
Furthermore,
this
reaction
leverage
commercially
available
carbon
isotologues
enable
the
direct
synthesis
of
isotopically
labeled
acids.
Mechanistic
studies
support
working
model
involving
thiol-catalyzed
radical
chain
wherein
atoms
are
delivered
substrate
via
CO2•–
as
key
reactive
intermediate.
Journal of the American Chemical Society,
Год журнала:
2022,
Номер
144(8), С. 3685 - 3695
Опубликована: Фев. 22, 2022
The
dearomative
dicarboxylation
of
stable
heteroaromatics
using
CO2
is
highly
challenging
but
represents
a
very
powerful
method
for
producing
synthetically
useful
dicarboxylic
acids,
which
can
potentially
be
employed
as
intermediates
biologically
active
molecules
such
natural
products
and
drug
leads.
However,
these
types
transformations
are
still
underdeveloped,
concise
methodologies
with
high
efficiency
(e.g.,
yield
selectivity
dicarboxylations)
have
not
been
reported.
We
herein
describe
new
electrochemical
protocol
the
radical
anion
(E1/2
=
-2.2
V
in
DMF
-2.3
CH3CN
vs
SCE)
that
produces
unprecedented
trans-oriented
2,3-dicarboxylic
acids
from
N-Ac-,
Boc-,
Ph-protected
indoles
exhibit
negative
reduction
potentials
(-2.50
to
-2.94
V).
On
basis
calculated
potentials,
N-protected
up
-3
smoothly
undergo
desired
dicarboxylation.
Other
heteroaromatics,
including
benzofuran,
benzothiophene,
electron-deficient
furans,
thiophenes,
1,3-diphenylisobenzofuran,
N-Boc-pyrazole,
also
more
positive
than
served
effective
substrates
dicarboxylations.
dicarboxylated
thus
obtained
derivatized
into
synthetic
compounds
few
steps.
show
how
monocarboxylation
achieved
selectively
by
choice
electrolyte,
solvent,
protic
additive;
this
strategy
was
then
applied
synthesis
an
octahydroindole-2-carboxylic
acid
(Oic)
derivative,
proline
analogue.
ACS Catalysis,
Год журнала:
2022,
Номер
12(7), С. 4103 - 4109
Опубликована: Март 18, 2022
Thiol
is
known
to
act
as
a
hydrogen
atom
transfer
catalyst
working
in
synergy
with
photocatalyst
photoredox
catalysis,
but
we
report
herein
that
an
arene
thiolate
appropriate
substituent
can
be
photoactivated
under
visible
light
function
both
strongly
reducing
electron-donating
redox
and
HAT
enable
catalytic
C–F
activation
of
trifluoromethyl
substrates
for
selective
hydrodefluorination
coupling
various
alkenes
the
presence
formate
salts.
These
reactions
demonstrate
promising
utility
arenethiolates
dual
photocatalysts.
The
synthetic
this
method
demonstrated
by
broad
scope
amenable
substrates,
including
trifluoromethylated
(hetero)arenes,
trifluoroacetates,
trifluoroacetamides,
which
exhibited
high
levels
chemoselectivity.
reaction
efficacy
allows
site-selective
late-stage
functionalization
multitrifluoromethylated
bioactive
compounds
pharmaceuticals
Nature Communications,
Год журнала:
2022,
Номер
13(1)
Опубликована: Янв. 17, 2022
Under
visible
light
irradiation,
o-phosphinophenolate
functions
as
an
easily
accessible
photoredox
catalyst
to
activate
trifluoromethyl
groups
in
trifluoroacetamides,
trifluoroacetates,
and
(hetero)arenes
deliver
corresponding
difluoromethyl
radicals.
It
works
relay
with
a
thiol
hydrogen
atom
transfer
(HAT)
enable
selective
defluoroalkylation
hydrodefluorination.
The
reaction
allows
for
the
facile
synthesis
of
broad
scope
difluoromethylene-incorporated
carbonyl
(hetero)aromatic
compounds,
which
are
valuable
fluorinated
intermediates
interest
pharmaceutical
industry.
ortho-diphenylphosphino
substituent,
is
believed
facilitate
photoinduced
electron
transfer,
plays
essential
role
redox
reactivity
phenolate.
In
addition
groups,
pentafluoroethyl
could
also
be
selectively
defluoroalkylated.
